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1.  Pichia fabianii blood infection in a premature infant in China: case report 
BMC Research Notes  2013;6:77.
Background
Invasive fungal infections caused by uncommon fungi have increased in recent years. Hospitalized low-birth-weight infants are at high risk for neonatal fungal infections. Pichia fabianii is a rare pathogen causing blood infection, which has reportedly caused only 4 cases of fungemia and 1 case of endocarditis worldwide. Here, we describe the first case of a P. fabianii blood infection in a premature infant in China.
Case presentation
On July 28th, a low-birth-weight (LBW, 1760 g) female infant born at 33+4 weeks of gestation was admitted to the pediatric intensive care unit with mild neonatal asphyxia. Until August 2nd, a mechanical respirator was used to assist respiration under the Continuous Positive Airway Pressure (CPAP) model. The baby had an increased body temperature and a fever. To prevent infection, Ceftriaxone Sodium (CS) was administered intravenously for three days, after which Cefepime was administered until August 13th. Chest X-rays showed suspected plaque-like shadows in the right lung. Blood cultures twice tested positive for fungal infection caused by Candida pelliculosa (recognized as Pichia fabianii later), which is first mis-identified by commercial kit. Hence, intravenous fluconazole was administered. However, cultures of other body fluids (e.g., urine, feces and sputum) tested negative for fungal infection. Routine tests and biochemistry of cerebrospinal fluid (CSF) were normal. Latex agglutination of Cryptococcus neoformans and fungi cultures in the CSF were also negative. After 14 days of intravenous fluconazole, blood was re-cultured, the result of which was negative. On August 30th, intravenous fluconazole was suspended. On Sep 3rd, the infant left the hospital in good health.
Conclusions
This is the first case of a blood infection caused by P. fabianii in a LBW premature female infant in China. Risk factors for fungal infection include premature birth, as well as mechanical invasive operation and antibacterial drug usage. Whether such risk factors necessitate prophylactic use of antifungal drugs is an important question that has yet to be fully addressed. Additionally, the pathogen P. fabianii collected in this study was resistant to amphotericin B (AMB) and itraconazole (ITR). With the exception of the azole-resistant endocarditis case, all other cases have not demonstrated such a resistance. Finally, commercial biochemical methods used in routine practice are limited in their ability to identify P. fabianii. Molecular genetic based methods are imperative for identification of uncommon fungal species from disseminated infections.
doi:10.1186/1756-0500-6-77
PMCID: PMC3599298
Pichia fabianii; Fungemia; Infant infection
2.  The TetR-Type Transcriptional Repressor RolR from Corynebacterium glutamicum Regulates Resorcinol Catabolism by Binding to a Unique Operator, rolO 
Applied and Environmental Microbiology  2012;78(17):6009-6016.
The rol (designated for resorcinol) gene cluster rolRHMD is involved in resorcinol catabolism in Corynebacterium glutamicum, and RolR is the TetR-type regulator. In this study, we investigated how RolR regulated the transcription of the rol genes in C. glutamicum. The transcription start sites and promoters of rolR and rolHMD were identified. Quantitative reverse transcription-PCR and promoter activity analysis indicated that RolR negatively regulated the transcription of rolHMD and of its own gene. Further, a 29-bp operator rolO was located at the intergenic region of rolR and rolHMD and was identified as the sole binding site for RolR. It contained two overlapping inverted repeats and they were essential for RolR-binding. The binding of RolR to rolO was affected by resorcinol and hydroxyquinol, which are the starting compounds of resorcinol catabolic pathway. These two compounds were able to dissociate RolR-rolO complex, thus releasing RolR from the complex and derepressing the transcription of rol genes in C. glutamicum. It is proposed that the binding of RolR to its operator rolO blocks the transcription of rolHMD and of its own gene, thus negatively regulated resorcinol degradation in C. glutamicum.
doi:10.1128/AEM.01304-12
PMCID: PMC3416628  PMID: 22706057
3.  LRRK2 Parkinson disease mutations enhance its microtubule association 
Human Molecular Genetics  2011;21(4):890-899.
Dominant missense mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common genetic causes of Parkinson disease (PD) and genome-wide association studies identify LRRK2 sequence variants as risk factors for sporadic PD. Intact kinase function appears critical for the toxicity of LRRK2 PD mutants, yet our understanding of how LRRK2 causes neurodegeneration remains limited. We find that most LRRK2 PD mutants abnormally enhance LRRK2 oligomerization, causing it to form filamentous structures in transfections of cell lines or primary neuronal cultures. Strikingly, ultrastructural analyses, including immuno-electron microscopy and electron microscopic tomography, demonstrate that these filaments consist of LRRK2 recruited onto part of the cellular microtubule network in a well-ordered, periodic fashion. Like LRRK2-related neurodegeneration, microtubule association requires intact kinase function and the WD40 domain, potentially linking microtubule binding and neurodegeneration. Our observations identify a novel effect of LRRK2 PD mutations and highlight a potential role for microtubules in the pathogenesis of LRRK2-related neurodegeneration.
doi:10.1093/hmg/ddr526
PMCID: PMC3263991  PMID: 22080837
4.  Comparision of Piceid and Resveratrol in Antioxidation and Antiproliferation Activities In Vitro 
PLoS ONE  2013;8(1):e54505.
Background
The clinic therapeutic effect of resveratrol is limited due to its low oral bioavailability. Piceid, a precursor of resveratrol, is the most abundant form of resveratrol in nature. A number of studies have hypothesized that piceid may have the same bioactivities like those of resveratrol. The aim of this work is to compare piceid with resveratrol in antioxidation and antiproliferation activities in vitro.
Methods
The antioxidative effects of resveratrol and piceid were evaluated by phenanthroline-Fe2+ method and H2O2-induced oxidative injury cell model. The antiproliferation effects were determined by MTT method in human liver tumor HepG2 cells, human breast cancer MDA-MB-231 cells and MCF-7 cells. The effects of resveratrol and piceid on the cell cycle and the apoptosis were evaluated by flow cytometry. Additionally, the uptake profiles of resveratrol and piceid in cancer cells were observed using fluorescence microscopy and clarified by LC-MS/MS.
Conclusion
Piceid exhibited higher scavenging activity against hydroxyl radicals than resveratrol in vitro. Resveratrol showed a significant protective effect against H2O2-induced cell damage. What is more, resveratrol had biphasic effects on tumor cells. Resveratrol and piceid only showed significant cytotoxicity on tumor cells at high concentration (≥50 µmol/L), while low concentration of resveratrol (<30 µmol/L) increased the cell viability. The principal effect of resveratrol and piceid on the viability of tumor cells was caused by the cell cycle arrest, while the effect on apoptosis was relatively minor. The reason that piceid showed lower biological activity than resveratrol at the same concentration was probably because piceid was more difficult in being uptaken by cells.
doi:10.1371/journal.pone.0054505
PMCID: PMC3546968  PMID: 23342161
5.  Accelerating Image Reconstruction in Dual-Head PET System by GPU and Symmetry Properties 
PLoS ONE  2012;7(12):e50540.
Positron emission tomography (PET) is an important imaging modality in both clinical usage and research studies. We have developed a compact high-sensitivity PET system that consisted of two large-area panel PET detector heads, which produce more than 224 million lines of response and thus request dramatic computational demands. In this work, we employed a state-of-the-art graphics processing unit (GPU), NVIDIA Tesla C2070, to yield an efficient reconstruction process. Our approaches ingeniously integrate the distinguished features of the symmetry properties of the imaging system and GPU architectures, including block/warp/thread assignments and effective memory usage, to accelerate the computations for ordered subset expectation maximization (OSEM) image reconstruction. The OSEM reconstruction algorithms were implemented employing both CPU-based and GPU-based codes, and their computational performance was quantitatively analyzed and compared. The results showed that the GPU-accelerated scheme can drastically reduce the reconstruction time and thus can largely expand the applicability of the dual-head PET system.
doi:10.1371/journal.pone.0050540
PMCID: PMC3530569  PMID: 23300527
6.  Tuina-Focused Integrative Chinese Medical Therapies for Inpatients with Low Back Pain: A Systematic Review and Meta-Analysis 
Objective. To evaluate the effectiveness of Tuina-focused integrative Chinese medical therapies (TICMT) on inpatients with low back pain (LBP). Methods. 6 English and Chinese databases were searched for randomized controlled trials (RCTs) of TICMT for in-patients with LBP. The methodological quality of the included RCTs was assessed based on PEDro scale. And the meta-analyses of TICMT for LBP on pain and functional status were conducted. Results. 20 RCTs were included. The methodological quality of the included RCTs was poor. The meta-analyses' results showed that TICMT had statistically significant effects on pain and functional status, especially Tuina plus Chinese herbal medicine (standardised mean difference, SMD: 1.17; 95% CI 0.75 to 1.60 on pain; SMD: 1.31; 95% CI 0.49 to 2.14 on functional status) and Tuina plus acupuncture (SMD: 0.94; 95% CI 0.38 to 1.50 on pain; SMD: 0.53; 95% CI 0.21 to 0.85 on functional status). But Tuina plus moxibustion or hot pack did not show significant improvements on pain. And the long-term evidence of TICMT was far from sufficient. Conclusions. The preliminary evidence from current studies suggests that TICMT might be effective complementary and alternative treatments for in-patients with LBP. However, the poor methodological quality of the included RCTs means that high-quality RCTs with long follow-up are warranted.
doi:10.1155/2012/578305
PMCID: PMC3543824  PMID: 23346207
7.  1-(1-Acetyl-piperidin-4-yl)-3-adamantan-1-yl-urea (AR9281) as a potent, selective, and orally available soluble epoxide hydrolase inhibitor with efficacy in rodent models of hypertension and dysglycemia 
1-(1-Acetyl-piperidin-4-yl)-3-adamantan-1-yl-urea 14a (AR9281), a potent and selective soluble epoxide hydrolase inhibitor, was recently tested in a phase 2a clinical setting for its effectiveness in reducing blood pressure and improving insulin-resistance in pre-diabetic patients. In a mouse model of diet induced obesity, AR9281 attenuated the enhanced glucose excursion following an intraperitoneal glucose tolerance test. AR9281 also attenuated the increase in blood pressure in angiotensin-II-induced hypertension in rats. These effects were dose-dependent and well correlated with inhibition of the sEH activity in whole blood, consistent with a role of sEH in the observed pharmacology in rodents.
doi:10.1016/j.bmcl.2010.12.042
PMCID: PMC3529200  PMID: 21211973
8.  Use of a Rich Internet Application Solution to Present Medical Images 
Journal of Digital Imaging  2011;24(6):967-978.
Browser with Rich Internet Application (RIA) Web pages could be a powerful user interface for handling sophisticated data and applications. Then the RIA solutions would be a potential method for viewing and manipulating the most data generated in clinical processes, which can accomplish the main functionalities as general picture archiving and communication system (PACS) viewing systems. The aim of this study is to apply the RIA technology to present medical images. Both Digital Imaging and Communications in Medicine (DICOM) and non-DICOM data can be handled by our RIA solutions. Some clinical data that are especially difficult to present using PACS viewing systems, such as ECG waveform, pathology virtual slide microscopic image, and radiotherapy plan, are as well demonstrated. Consequently, clinicians can use browser as a unique interface for acquiring all the clinical data located in different departments and information systems. And the data could be presented appropriately and processed freely by adopting the RIA technologies.
Electronic supplementary material
The online version of this article (doi:10.1007/s10278-011-9374-1) contains supplementary material, which is available to authorized users.
doi:10.1007/s10278-011-9374-1
PMCID: PMC3222552  PMID: 21424328
PACS; Clinical application; Clinical image viewing; DICOM; XML; RIA
9.  Chinese Massage Combined with Herbal Ointment for Athletes with Nonspecific Low Back Pain: A Randomized Controlled Trial 
Non-specific low back pain (NLBP) is an increasing health problem for athletes. This randomized controlled trial was designed to investigate the effects of Chinese massage combined with herbal ointment for NLBP. 110 athletes with NLBP were randomly assigned to experimental group with Chinese massage combined with herbal ointment or control group with simple massage therapy. The primary outcome was pain by Chinese Short Form McGill Pain Questionnaire (C-SFMPQ). The secondary outcome was local muscle stiffness by Myotonometer. After 4 weeks, the experimental group experienced significant improvements in C-SFMPQ and in local muscle stiffness compared with control group (between-group difference in mean change from baseline, −1.24 points, P = 0.005 in sensory scores; −3.14 points, P < 0.001 in affective scores; −4.39 points, P < 0.001 in total scores; −0.64 points, P = 0.002 in VAS; −1.04 points, P = 0.005 in local muscle stiffness during relaxation state). The difference remained at one month followup, but it was only significant in affective scores (−2.83 points, P < 0.001) at three months followup. No adverse events were observed. These findings suggest that Chinese massage combined with herbal ointment may be a beneficial complementary and alternative therapy for athletes with NLBP.
doi:10.1155/2012/695726
PMCID: PMC3522503  PMID: 23258996
10.  Analysis of the Clonality of Candida tropicalis Strains from a General Hospital in Beijing Using Multilocus Sequence Typing 
PLoS ONE  2012;7(11):e47767.
Multilocus sequence typing (MLST) based on six loci was used to analyze the relationship of 58 Candida tropicalis isolates from individual patients in a general hospital in Beijing, China. A total of 52 diploid sequence types (DSTs) were generated by the MLST, all of which were new to the central database. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dendrograms were constructed, which showed that the 58 isolates were distributed robustly and 6 main groups were clustered regardless of the specimen source and medical department. The minimum spanning tree (MST) of the 58 isolates (52 DSTs) and all 401 isolates (268 DSTs) in the C. tropicalis central database (http://pubmlst.org/ctropicalis/) indicated that the isolates in this study clustered in three relative pure clonal complexes, and 2 clustered with isolates from Taiwan, Belgium, Brazil, and the US. This study presents the first MLST analysis of C. tropicalis isolates from Mainland China, which may be useful for further studies on the similarity, genetic relationship, and molecular epidemiology of C. tropicalis strains worldwide.
doi:10.1371/journal.pone.0047767
PMCID: PMC3494695  PMID: 23152759
11.  Emergency transcatheter arterial embolization for patients with acute massive duodenal ulcer hemorrhage 
AIM: To evaluate the efficacy and safety of emergency transcatheter arterial embolization (ETAE) for patients with acute massive duodenal ulcer hemorrhage.
METHODS: Twenty-nine consecutive patients with acute massive bleeding of duodenal ulcer were admitted to our hospital from 2006 to 2011. Superselective angiography of the celiac and gastroduodenal arteries was performed to find out the bleeding sites before ETAE, then, embolotherapy was done with gelatin sponge particles or microstrips via a 5 French angiographic catheter or 3 French microcatheter. After ETAE, further superior mesenteric arteriography was undertaken in case collateral circulation supplied areas of the duodenal ulcer. Technical and clinical success rates were analyzed. Changes in the mucous membrane were observed using endoscopy following ETAE.
RESULTS: Angiography showed active bleeding with extravasation of contrast medium in seven cases with a 24% positive rate of celiac artery bleeding, and in 19 cases with a 65.5% rate of gastroduodenal artery bleeding. There were no angiographic signs of bleeding in three patients who underwent endoscopy prior to ETAE. Twenty-six patients achieved immediate hemostasis and technical success rate reached 90%. No hemostasis was observed in 27 patients within 30 d after ETAE and clinical success rate was 93%. Recurrent hemorrhage occurred in two patients who drank a lot of wine who were treated by a second embolotherapy in the same way. Five patients underwent transient ischem with light abdominal pain under xiphoid, spontaneous restoration without special treatment. No mucous necrosis happened to 29 cases for ischem of gastroduodenal arteries embolized.
CONCLUSION: ETAE is an effective and safe measure to control acute massive bleeding of duodenal ulcer.
doi:10.3748/wjg.v18.i34.4765
PMCID: PMC3442216  PMID: 23002347
Transcatheter embolization; Massive bleeding; Duodenal ulcer; Angiography
12.  The GUDMAP database – an online resource for genitourinary research 
Development (Cambridge, England)  2011;138(13):2845-2853.
The GenitoUrinary Development Molecular Anatomy Project (GUDMAP) is an international consortium working to generate gene expression data and transgenic mice. GUDMAP includes data from large-scale in situ hybridisation screens (wholemount and section) and microarray gene expression data of microdissected, laser-captured and FACS-sorted components of the developing mouse genitourinary (GU) system. These expression data are annotated using a high-resolution anatomy ontology specific to the developing murine GU system. GUDMAP data are freely accessible at www.gudmap.org via easy-to-use interfaces. This curated, high-resolution dataset serves as a powerful resource for biologists, clinicians and bioinformaticians interested in the developing urogenital system. This paper gives examples of how the data have been used to address problems in developmental biology and provides a primer for those wishing to use the database in their own research.
doi:10.1242/dev.063594
PMCID: PMC3188593  PMID: 21652655
Database; Gene expression; Genitourinary; In situ hybridisation; Microarray
13.  Disruption of the Phospholipase D Gene Attenuates the Virulence of Aspergillus fumigatus 
Infection and Immunity  2012;80(1):429-440.
Aspergillus fumigatus is the most prevalent airborne fungal pathogen that induces serious infections in immunocompromised patients. Phospholipases are key enzymes in pathogenic fungi that cleave host phospholipids, resulting in membrane destabilization and host cell penetration. However, knowledge of the impact of phospholipases on A. fumigatus virulence is rather limited. In this study, disruption of the pld gene encoding phospholipase D (PLD), an important member of the phospholipase protein family in A. fumigatus, was confirmed to significantly decrease both intracellular and extracellular PLD activity of A. fumigatus. The pld gene disruption did not alter conidial morphological characteristics, germination, growth, and biofilm formation but significantly suppressed the internalization of A. fumigatus into A549 epithelial cells without affecting conidial adhesion to epithelial cells. Importantly, the suppressed internalization was fully rescued in the presence of 100 μM phosphatidic acid, the PLD product. Indeed, complementation of pld restored the PLD activity and internalization capacity of A. fumigatus. Phagocytosis of A. fumigatus conidia by J774 macrophages was not affected by the absence of the pld gene. Pretreatment of conidia with 1-butanol and a specific PLD inhibitor decreased the internalization of A. fumigatus into A549 epithelial cells but had no effect on phagocytosis by J774 macrophages. Finally, loss of the pld gene attenuated the virulence of A. fumigatus in mice immunosuppressed with hydrocortisone acetate but not with cyclophosphamide. These data suggest that PLD of A. fumigatus regulates its internalization into lung epithelial cells and may represent an important virulence factor for A. fumigatus infection.
doi:10.1128/IAI.05830-11
PMCID: PMC3255654  PMID: 22083709
14.  Measuring T2 In Vivo With J-Difference Editing: Application to GABA at 3 Tesla 
Purpose
To develop an experimental approach for determining in vivo transverse relaxation rates (T2) of metabolites that are detected by spectral editing without using simulations, and to demonstrate this approach to measure the T2 of γ-aminobutyric acid (GABA).
Materials and Methods
The proposed method first determines the TE-dependence of the edited signals using measurements in a pure phantom solution (10 mM γ-aminobutyric acid; GABA); the phantom T2 is also determined. Once the editing echo time (TE) -modulation pattern is known, it can then be used to determine T2 in vivo. The method was applied to measure GABA T2 in the occipital lobe of five healthy adult subjects at 3T, using a J-difference editing method. Unwanted macromolecular contributions to the GABA signal were also measured.
Results
The in vivo T2 of edited GABA signal was 88 ± 12 ms; this preliminary result is somewhat shorter than other metabolite T2 values in the literature at this field strength.
Conclusion
Spectral editing methods are now widely used to detect low concentration metabolites, such as GABA, but to date no edited acquisition methods have been proposed for the measurement of transverse relaxation times (T2). The method described has been successfully applied to measuring the T2 of GABA.
doi:10.1002/jmri.22865
PMCID: PMC3377980  PMID: 22045601
edited MR spectroscopy; transverse relaxation; T2; GABA; brain
15.  Suppressed liver tumorigenesis in fat-1 mice with elevated omega-3 fatty acids is associated with increased omega-3 derived lipid mediators and reduced TNF-α 
Carcinogenesis  2011;32(6):897-903.
Liver tumors, particularly hepatocellular carcinoma (HCC), are a major cause of morbidity and mortality worldwide. The development of HCC is mostly associated with chronic inflammatory liver disease of various etiologies. Previous studies have shown that omega-3 (n-3) polyunsaturated fatty acids (PUFAs) dampen inflammation in the liver and decrease formation of tumor necrosis factor (TNF)-α.
In this study, we used the fat-1 transgenic mouse model, which endogenously forms n-3 PUFA from n-6 PUFA to determine the effect of an increased n-3 PUFA tissue status on tumor formation in the diethylnitrosamine (DEN)-induced liver tumor model.
Our results showed a decrease in tumor formation, in terms of size and number, in fat-1 mice compared with wild-type littermates. Plasma TNF-α levels and liver cyclooxygenase-2 expression were markedly lower in fat-1 mice. Furthermore, there was a decreased fibrotic activity in the livers of fat-1 mice. Lipidomics analyses of lipid mediators revealed significantly increased levels of the n-3 PUFA-derived 18-hydroxyeicosapentaenoic acid (18-HEPE) and 17-hydroxydocosahexaenoic acid (17-HDHA) in the livers of fat-1 animals treated with DEN. In vitro experiments showed that 18-HEPE and 17-HDHA could effectively suppress lipopolysacharide-triggered TNF-α formation in a murine macrophage cell line.
The results of this study provide evidence that an increased tissue status of n-3 PUFA suppresses liver tumorigenesis, probably through inhibiting liver inflammation. The findings also point to a potential anticancer role for the n-3 PUFA-derived lipid mediators 18-HEPE and 17-HDHA, which can downregulate the important proinflammatory and proproliferative factor TNF-α.
doi:10.1093/carcin/bgr049
PMCID: PMC3106436  PMID: 21421544
16.  Impact of Maturational Status on the Ability of Osteoblasts to Enhance the Hematopoietic Function of Stem and Progenitor Cells 
Journal of Bone and Mineral Research  2010;26(5):1111-1121.
Osteoblasts (OBs) exert a prominent regulatory effect on hematopoietic stem cells (HSCs). We evaluated the difference in hematopoietic expansion and function in response to co-culture with OBs at various stages of development. Murine calvarial OBs were seeded directly (fresh) or cultured for 1, 2, or 3 weeks prior to seeding with 1000 Lin-Sca1 + cKit+ (LSK) cells for 1 week. Significant increases in the following hematopoietic parameters were detected when comparing co-cultures of fresh OBs to co-cultures containing OBs cultured for 1, 2, or 3 weeks: total hematopoietic cell number (up to a 3.4-fold increase), total colony forming unit (CFU) number in LSK progeny (up to an 18.1-fold increase), and percentage of Lin-Sca1+ cells (up to a 31.8-fold increase). Importantly, these studies were corroborated by in vivo reconstitution studies in which LSK cells maintained in fresh OB co-cultures supported a significantly higher level of chimerism than cells maintained in co-cultures containing 3-week OBs. Characterization of OBs cultured for 1, 2, or 3 weeks with real-time PCR and functional mineralization assays showed that OB maturation increased with culture duration but was not affected by the presence of LSK cells in culture. Linear regression analyses of multiple parameters measured in these studies show that fresh, most likely more immature OBs better promote hematopoietic expansion and function than cultured, presumably more mature OBs and suggest that the hematopoiesis-enhancing activity is mediated by cells present in fresh OB cultures de novo. © 2011 American Society for Bone and Mineral Research.
doi:10.1002/jbmr.302
PMCID: PMC3179304  PMID: 21542011
OSTEOBLASTS; HEMATOPOIETIC STEM CELLS; HEMATOPOIETIC NICHE; CALCIUM DEPOSITION; MOUSE
17.  14-3-3 regulates the LNK/JAK2 pathway in mouse hematopoietic stem and progenitor cells 
The Journal of Clinical Investigation  2012;122(6):2079-2091.
Hematopoietic stem and progenitor cell (HSPC) functions are governed by intricate signaling networks. The tyrosine kinase JAK2 plays an essential role in cytokine signaling during hematopoiesis. The adaptor protein LNK is a critical determinant of this process through its inhibitory interaction with JAK2, thereby limiting HSPC self-renewal. LNK deficiency promotes myeloproliferative neoplasm (MPN) development in mice, and LNK loss-of-function mutations are found in human MPNs, emphasizing its pivotal role in normal and malignant HSPCs. Here, we report the identification of 14-3-3 proteins as LNK binding partners. 14-3-3 interfered with the LNK-JAK2 interaction, thereby alleviating LNK inhibition of JAK2 signaling and cell proliferation. Binding of 14-3-3 required 2 previously unappreciated serine phosphorylation sites in LNK, and we found that their phosphorylation is mediated by glycogen synthase kinase 3 and PKA kinases. Mutations of these residues abrogated the interaction and augmented the growth inhibitory function of LNK. Conversely, forced 14-3-3 binding constrained LNK function. Furthermore, interaction with 14-3-3 sequestered LNK in the cytoplasm away from the plasma membrane-proximal JAK2. Importantly, bone marrow transplantation studies revealed an essential role for 14-3-3 in HSPC reconstitution that can be partially mitigated by LNK deficiency. We believe that, together, this work implicates 14-3-3 proteins as novel and positive HSPC regulators by impinging on the LNK/JAK2 pathway.
doi:10.1172/JCI59719
PMCID: PMC3366400  PMID: 22546852
18.  Ultrasound sonication with microbubbles disrupts blood vessels and enhances tumor treatments of anticancer nanodrug 
Ultrasound (US) sonication with microbubbles (MBs) has the potential to disrupt blood vessels and enhance the delivery of drugs into the sonicated tissues. In this study, mouse ear tumors were employed to investigate the therapeutic effects of US, MBs, and pegylated liposomal doxorubicin (PLD) on tumors. Tumors started to receive treatments when they grew up to about 15 mm3 (early stage) with injection of PLD 10 mg/kg, or up to 50 mm3 (medium stage) with PLD 6 (or 4) mg/kg. Experiments included the control, PLD alone, PLD + MBs + US, US alone, and MBs + US groups. The procedure for the PLD + MBs + US group was that PLD was injected first, MB (SonoVue) injection followed, and then US was immediately sonicated on the tumor. The results showed that: (1) US sonication with MBs was always able to produce a further hindrance to tumor growth for both early and medium-stage tumors; (2) for the medium-stage tumors, 6 mg/kg PLD alone was able to inhibit their growth, while it did not work for 4 mg/kg PLD alone; (3) with the application of MBs + US, 4 mg/kg PLD was able to inhibit the growth of medium-stage tumors; (4) for early stage tumors after the first treatment with a high dose of PLD alone (10 mg/kg), the tumor size still increased for several days and then decreased (a biphasic pattern); (5) MBs + US alone was able to hinder the growth of early stage tumors, but unable to hinder that of medium stage tumors. The results of histological examinations and blood perfusion measurements indicated that the application of MBs + US disrupts the tumor blood vessels and enhances the delivery of PLD into tumors to significantly inhibit tumor growth.
doi:10.2147/IJN.S29514
PMCID: PMC3356217  PMID: 22619550
ultrasound; microbubbles; nanodrug; mouse tumor; vascular disruption; tumor growth response
19.  Mechanisms of regulation of oligodendrocyte development by p38 MAP kinase 
The Journal of Neuroscience  2010;30(33):11011-11027.
Many extracellular and intrinsic factors regulate oligodendrocyte development, but their signaling pathways remain poorly understood. While the p38 mitogen activated protein kinase (MAPK)-dependent pathway is implicated in oligodendrocyte progenitor cell (OPC) lineage progression, its molecular targets involved in myelinogenesis are largely unidentified. We have analyzed mechanisms by which p38MAPK regulates oligodendrocyte development and demonstrate that p38MAPK inhibition prevents OPC lineage progression, and inhibits MBP promoter activity and Sox10 function. In white matter tissue, differential levels of MAPK phosphorylation are observed in oligodendrocyte lineage cells. Phosphorylated p38MAPK was found in CC1- and CNP-expressing differentiated oligodendrocytes of the adult brain, and was temporally associated with a decline in the levels of phosphorylated ERK in cells of this lineage. PDGF stimulates the phosphorylation of ERK, p38MAPK and JNK, and p38MAPK inhibition was associated with increased ERK, JNK and c-Jun phosphorylation. In the presence of PDGF, simultaneous inhibition of p38MAPK and either MEK or JNK significantly alleviates the repression of myelin gene expression and lineage progression induced by p38MAPK inhibition alone. Dominant negative c-Jun reverses the inhibition of myelin promoter activity by active MEK1 or dominant negative p38MAPKα mutants, and phosphorylated c-Jun was detected at the MBP promoter following p38MAPK inhibition, indicating c-Jun as a negative mediator of p38MAPK action. Our findings indicate that p38MAPK activity in the brain supports myelin gene expression through distinct mechanisms via positive and negative regulatory targets. We show that oligodendrocyte differentiation involves p38-mediated Sox10 regulation and crosstalk with parallel ERK and JNK pathways to repress c-Jun activity.
doi:10.1523/JNEUROSCI.2546-10.2010
PMCID: PMC3327889  PMID: 20720108
MAP kinases; myelin; oligodendrocyte; development; cross-talk; gene expression
20.  Antidepressant-Like Activity of the Ethanolic Extract from Uncaria lanosa Wallich var. appendiculata Ridsd in the Forced Swimming Test and in the Tail Suspension Test in Mice 
This study investigated the antidepressant activity of ethanolic extract of U. lanosa Wallich var. appendiculata Ridsd (ULEtOH) for two-weeks administrations by using FST and TST on mice. In order to understand the probable mechanism of antidepressant-like activity of ULEtOH in FST and TST, the researchers measured the levels of monoamines and monoamine oxidase activities in mice brain, and combined the antidepressant drugs (fluoxetine, imipramine, maprotiline, clorgyline, bupropion and ketanserin). Lastly, the researchers analyzed the content of RHY in the ULEtOH. The results showed that ULEtOH exhibited antidepressant-like activity in FST and TST in mice. ULEtOH increased the levels of 5-HT and 5-HIAA in cortex, striatum, hippocampus, and hypothalamus, the levels of NE and MHPG in cortex and hippocampus, the level of NE in striatum, and the level of DOPAC in striatum. Two-week injection of IMI, CLO, FLU and KET enhanced the antidepressant-like activity of ULEtOH. ULEtOH inhibited the activity of MAO-A. The amount of RHY in ULEtOH was 17.12 mg/g extract. Our findings support the view that ULEtOH exerts antidepressant-like activity. The antidepressant-like mechanism of ULEtOH may be related to the increase in monoamines levels in the hippocampus, cortex, striatum, and hypothalamus of mice.
doi:10.1155/2012/497302
PMCID: PMC3332070  PMID: 22567032
21.  Sox17 regulates the Wnt/beta-catenin signaling pathway in oligodendrocyte progenitor cells 
The SRY-box (Sox) transcription factors regulate oligodendrocyte differentiation, but their signaling targets are largely unknown. We have identified a major signal transduction pathway regulated by Sox17 in the oligodendrocyte lineage. Microarray analysis in oligodendrocyte progenitor cells (OPCs) after Sox17 attenuation revealed upregulated genes associated with cell cycle control and activation of the Wnt/beta-catenin-pathway. Sox17 knockdown also increases the levels of cyclinD1, Axin2 and activated beta-catenin. In OPCs, the expression pattern of Sox17, cyclinD1 and sFRP1 in the presence of PDGF was coordinately accelerated by addition of thyroid hormone, indicating differentiation-induced regulation of Sox17 targets. In developing white matter, decreased total beta-catenin, activated beta-catenin, and cyclinD1 levels coincided with the peak of Sox17 expression, and immunoprecipitates showed a developmentally-regulated interaction between Sox17, TCF4 and beta-catenin proteins. In OPCs, PDGF stimulated phosphorylation of GSK3beta and the Wnt co-receptor LRP6, and enhanced beta-catenin-dependent gene expression. Sox17 overexpression inhibited PDGF-induced TOPFLASH and cyclinD1 promoter activity, and decreased endogenous cyclinD1, activated beta-catenin (ABC) as well as total beta-catenin levels. Recombinant Sox17 prevented Wnt3a from repressing myelin protein expression, and inhibition of Sox17-mediated proteasomal degradation of beta-catenin blocked myelin protein induction. These results indicate that Sox17 suppresses cyclinD1 expression and cell proliferation by directly antagonizing beta-catenin, whose activity in OPCs is stimulated not only by Wnt3a, but also by PDGF. Our identification of downstream targets of Sox17 thus defines signaling pathways and molecular mechanisms in OPCs that are regulated by Sox17 during cell cycle exit and the onset of differentiation in oligodendrocyte development.
doi:10.1523/JNEUROSCI.3343-11.2011
PMCID: PMC3227525  PMID: 21957254
22.  Leucine Deprivation Increases Hepatic Insulin Sensitivity via GCN2/mTOR/S6K1 and AMPK Pathways 
Diabetes  2011;60(3):746-756.
OBJECTIVE
We have previously shown that serum insulin levels decrease threefold and blood glucose levels remain normal in mice fed a leucine-deficient diet, suggesting increased insulin sensitivity. The goal of the current study is to investigate this possibility and elucidate the underlying cellular mechanisms.
RESEARCH DESIGN AND METHODS
Changes in metabolic parameters and expression of genes and proteins involved in regulation of insulin sensitivity were analyzed in mice, human HepG2 cells, and mouse primary hepatocytes under leucine deprivation.
RESULTS
We show that leucine deprivation improves hepatic insulin sensitivity by sequentially activating general control nonderepressible (GCN)2 and decreasing mammalian target of rapamycin/S6K1 signaling. In addition, we show that activation of AMP-activated protein kinase also contributes to leucine deprivation–increased hepatic insulin sensitivity. Finally, we show that leucine deprivation improves insulin sensitivity under insulin-resistant conditions.
CONCLUSIONS
This study describes mechanisms underlying increased hepatic insulin sensitivity under leucine deprivation. Furthermore, we demonstrate a novel function for GCN2 in the regulation of insulin sensitivity. These observations provide a rationale for short-term dietary restriction of leucine for the treatment of insulin resistance and associated metabolic diseases.
doi:10.2337/db10-1246
PMCID: PMC3046835  PMID: 21282364
23.  Neurodevelopmental Consequences of Sub-Clinical Carbon Monoxide Exposure in Newborn Mice 
PLoS ONE  2012;7(2):e32029.
Carbon monoxide (CO) exposure at high concentrations results in overt neurotoxicity. Exposure to low CO concentrations occurs commonly yet is usually sub-clinical. Infants are uniquely vulnerable to a variety of toxins, however, the effects of postnatal sub-clinical CO exposure on the developing brain are unknown. Apoptosis occurs normally within the brain during development and is critical for synaptogenesis. Here we demonstrate that brief, postnatal sub-clinical CO exposure inhibits developmental neuroapoptosis resulting in impaired learning, memory, and social behavior. Three hour exposure to 5 ppm or 100 ppm CO impaired cytochrome c release, caspase-3 activation, and apoptosis in neocortex and hippocampus of 10 day old CD-1 mice. CO increased NeuN protein, neuronal numbers, and resulted in megalencephaly. CO-exposed mice demonstrated impaired memory and learning and reduced socialization following exposure. Thus, CO-mediated inhibition of neuroapoptosis might represent an important etiology of acquired neurocognitive impairment and behavioral disorders in children.
doi:10.1371/journal.pone.0032029
PMCID: PMC3277503  PMID: 22348142
25.  Multicenter Clinical Study for Evaluation of Efficacy and Safety of Transdermal Fentanyl Matrix Patch in Treatment of Moderate to Severe Cancer Pain in 474 Chinese Cancer Patients 
Objective
Although a new matrix formulation fentanyl has been used throughout the world for cancer pain management, few data about its efficacy and clinical outcomes associated with its use in Chinese patients have been obtained. This study aimed to assess the efficacy and safety of the new system in Chinese patients with moderate to severe cancer pain.
Methods
A total of 474 patients with moderate to severe cancer pain were enrolled in this study and were treated with the new transdermal fentanyl matrix patch (TDF) up to 2 weeks. All the patients were asked to record pain intensity, side effects, quality of life (QOL), adherence and global satisfaction. The initial dose of fentanyl was 25 μg/h titrated with opioid or according to National Comprehensive Cancer Network (NCCN) guidelines. Transdermal fentanyl was changed every three days.
Results
After 2 weeks. The mean pain intensity of the 459 evaluated patients decreased significantly from 5.63±1.26 to 2.03±1.46 (P<0.0001). The total remission rate was 91.29%, of which moderate remission rate 53.16%, obvious remission rate 25.49% and complete remission rate 12.64%. The rate of adverse events was 33.75%, 18.78% of which were moderate and 3.80% were severe. The most frequent adverse events were constipation and nausea. No fatal events were observed. The quality of life was remarkably improved after the treatment (P<0.0001).
Conclusion
The new TDF is effective and safe in treating patients with moderate to severe cancer pain, and can significantly improve the quality of life.
doi:10.1007/s11670-011-0317-7
PMCID: PMC3551305  PMID: 23359267
Transdermal fentanyl matrix patch (TDF); Cancer pain; Efficacy; Safety; Quality of life

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