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1.  Co-inheritance of two ABCC8 mutations causing an unresponsive congenital hyperinsulinism: Clinical and functional characterization of two novel ABCC8 mutations 
Gene  2012;516(1):122-125.
Congenital hyperinsulinism (CHI) occurs as a consequence of unregulated insulin secretion from the pancreatic beta-cells. Severe recessive mutations and milder dominant mutations have been described in the ABCC8 and KCNJ11 genes encoding SUR1 and Kir6.2 subunits of the beta-cell ATP-sensitive K(+) channel. Here we report two patients with CHI unresponsive to medical therapy with diazoxide. Sequencing analysis identified a compound heterozygous mutation in ABCC8 in both patients. The first one is a carrier for the known mild dominant mutation p.Glu1506Lys jointly with the novel mutation p.Glu1323Lys. The second carries the p.Glu1323Lys mutation and a second novel mutation, p.Met1394Arg. Functional studies of both novel alleles showed reduced or null cell surface expression, typical of recessive mutations. Compound heterozygous mutations in congenital hyperinsulinism result in complex interactions. Studying these mechanisms can improve the knowledge of this disease and modify its therapy.
doi:10.1016/j.gene.2012.12.055
PMCID: PMC3600632  PMID: 23266803
Congenital hyperinsulinism; Mutation; ABCC8; Functional study
2.  Bidirectional Relations between Temperament and Parenting Styles in Chinese Children 
The present study examined bidirectional relations between child temperament and parenting styles in a sample (n = 425) of Chinese children during elementary school period (age range = 6 to 9 years at Wave 1). Using two waves (3.8 years apart) of longitudinal data, we tested two hypotheses: (1) whether child temperament (effortful control and anger/frustration) at Wave 1 predicts parenting styles (authoritative and authoritarian parenting) at Wave 2, controlling for Wave 1 parenting; and (2) whether parenting styles at Wave 1 predict Wave 2 temperament, controlling for Wave 1 temperament. We found support for bidirectional relations between temperament and authoritarian parenting, such that higher effortful control and lower anger/frustration were associated with higher authoritarian parenting across time and in both directions. There were no significant cross-time associations between children’s temperament and authoritative parenting. These findings extend the previous tests of transactional relations between child temperament and parenting in Chinese children and are consistent with the cultural values toward effortful control and control of anger/frustration in Chinese society.
doi:10.1177/0165025412460795
PMCID: PMC3591485  PMID: 23482684
temperament; parenting styles; bidirectional
3.  H2A.Z Nucleosome Positioning Has No Impact on Genetic Variation in Drosophila Genome 
PLoS ONE  2013;8(3):e58295.
Nucleosome occupancy results in complex sequence variation rate heterogeneity by either increasing mutation rate or inhibiting DNA repair in yeast, fish, and human. H2A.Z nucleosome is extensively involved in gene transcription activation and regulation. To test whether H2A.Z nucleosome has the similar impact on sequence variability in the Drosophila genome, we profiled the H2A.Z nucleosome occupancy and sequence variation rate at gene ends and splicing sites. Consistent with previous studies, H2A.Z nucleosome positioning helps to demarcate the borders of exons. Nucleosome occupancy is anticorrelated with sequence divergence rate in the regions flanking transcription start sites and splicing sites. However, there is no rate heterogeneity between the linker DNA and H2A.Z nucleosomal DNA regardless of nucleosome occupancy, fuzziness, positioning in promoter, coding, and intergenic regions, young or old genes. But the rate at intergenic nucleosomes and the flanking linker regions is higher than that at the genic counterparts. Further analyses found that the high sequence divergence rate in the promoter regions that are usually nucleosome depleted regions may be likely resulted from the high mutation rate in the enriched tandem repeats. Interestingly, within nucleosomes spanning splicing sites, sequence variability of nucleosomal DNA significantly increases from the end within exons to the other end protruding into introns. The relaxed functional constraint in introns contributes to the high rate of nucleosomal DNA residing in introns while the strict functional constraint in exons maintains the low rate of nucleosomal DNA residing in exons. Taken together, H2A.Z nucleosome occupancy has no effect on sequence variability of Drosophila genome, which is likely determined by local sequence composition and the concomitant selection pressure.
doi:10.1371/journal.pone.0058295
PMCID: PMC3589275  PMID: 23472174
4.  The protein-tyrosine kinase Syk interacts with the C-terminal region of tensin2 
Biochimica et Biophysica Acta  2011;1823(2):199-205.
Syk is a 72-kDa protein-tyrosine kinase that regulates signaling through multiple cell surface receptors including those for antigens, immunoglobulins and proteins of the extracellular matrix. As part of its function, Syk binds a variety of downstream effectors through interactions that are often mediated by motifs that recognize phosphotyrosines. In a search for novel Syk-interacting proteins by yeast two-hybrid analysis, we identified tensin2 as a Syk-binding protein. Syk interacts with a fragment of tensin2 located near the C-terminus that contains SH2 and PTB domains. In epithelial cells, tensin2 localizes both to focal adhesions and to large cytoplasmic puncta. It is within these punctuate structures that Syk and tensin2 are co-localized. The clustering of Syk within these structures leads to its phosphorylation on tyrosine.
doi:10.1016/j.bbamcr.2011.10.001
PMCID: PMC3273629  PMID: 22019427
Syk; tensin2; tyrosine phosphorylation; signal transduction
5.  Engineered interaction between SUR1 and Kir6.2 that enhances ATP sensitivity in KATP channels 
The Journal of General Physiology  2012;140(2):175-187.
The ATP-sensitive potassium (KATP) channel consisting of the inward rectifier Kir6.2 and SUR1 (sulfonylurea receptor 1) couples cell metabolism to membrane excitability and regulates insulin secretion. Inhibition by intracellular ATP is a hallmark feature of the channel. ATP sensitivity is conferred by Kir6.2 but enhanced by SUR1. The mechanism by which SUR1 increases channel ATP sensitivity is not understood. In this study, we report molecular interactions between SUR1 and Kir6.2 that markedly alter channel ATP sensitivity. Channels bearing an E203K mutation in SUR1 and a Q52E in Kir6.2 exhibit ATP sensitivity ∼100-fold higher than wild-type channels. Cross-linking of E203C in SUR1 and Q52C in Kir6.2 locks the channel in a closed state and is reversible by reducing agents, demonstrating close proximity of the two residues. Our results reveal that ATP sensitivity in KATP channels is a dynamic parameter dictated by interactions between SUR1 and Kir6.2.
doi:10.1085/jgp.201210803
PMCID: PMC3409095  PMID: 22802363
6.  Distinct different sensitivity of Treg and Th17 cells to Fas-mediated apoptosis signaling in patients with acute coronary syndrome 
Objective: An imbalance in CD4+CD25+ regulatory T (Treg) cells and Th17 cells has been found to correlate to occurrence of acute coronary syndrome [ACS, including unstable angina (UA) and acute myocardial infarction (AMI)]. However, the mechanisms of Th17/Treg imbalance in ACS patients are still unclear. The purpose of this study is to investigate the possibility of differences in sensitivity of Th17 and Tregs to Fas-mediated apoptosis which could lead to Th17/Treg imbalance in ACS patients. Methods: We examined the apoptosis of Th17 and Treg cells, apoptosis-related Fas/Fas ligand(FasL) pathway, and inflammatory markers in patients with AMI, UA, stable angina (SA) and controls by Flow cytometry and ELISA. Then we analysed the correlation of inflammatory markers and sFasL to Treg apoptosis, and the effect of anti-FasL antibody on Treg apoptois in vitro. Results: Our study demonstrated that apoptotic Tregs, Fas and FasL expression, Caspase-3 activity of Tregs were significantly higher in ACS patients than those in NCA and SA patients (all P < 0.05). The percentage of apoptotic Tregs is positively correlated with the levels of inflammatory markers and sFasL. In vitro incubation of peripheral blood mononuclear cells from ACS patients with anti-FasL antibody resulted in a markedly reduction of apoptotic Treg cells. However, there were no significant differences in apoptotic Th17 cells and in Fas and FasL expression for Th17 cells between the four groups (all P >0.05). Conclusions: Tregs, but not Th17 cells, become apoptotic through Fas/FasL pathway, which contributed to reduction of Tregs leading to an imbalance between Th17 and Treg cells. This could be the mechanism underlying Th17/Treg imbalance and occurrence of ACS.
PMCID: PMC3544239  PMID: 23330016
Apoptosis; Fas; Fas ligand; T helper 17; regulatory T cells; acute coronary syndrome
7.  N-(7-Dibromo­methyl-5-methyl-1,8-naphthyridin-2-yl)acetamide–pyrrolidine-2,5-dione (1/1) 
In the title co-crystal, C12H11Br2N3O·C4H5NO2, the naphthyridine derivative and the pyrrolidine-2,5-dione mol­ecules have crystallographic mirror-plane symmetry with all non-H atoms, except the Br atom, located on the mirror plane. In the crystal, N—H⋯N, N—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into heterodimers. These dimers are further linked into a one-dimensional structure along [010] by weak C—Br⋯O inter­actions [Br⋯O = 3.028 (5) Å and C—Br⋯O = 158.52 (4)°].
doi:10.1107/S1600536812051112
PMCID: PMC3569222  PMID: 23424445
8.  Relative Expression of a Dominant Mutated ABCC8 Allele Determines the Clinical Manifestation of Congenital Hyperinsulinism 
Diabetes  2011;61(1):258-263.
Congenital hyperinsulinism (CHI) is most commonly caused by mutations in the β-cell ATP-sensitive K+ (KATP) channel genes. Severe CHI was diagnosed in a 1-day-old girl; the mother’s cousin and sister had a similar phenotype. ABCC8 gene sequencing (leukocyte DNA) revealed a heterozygous, exon 37, six–base pair in-frame insertion mutation in the affected patient and aunt but also in her unaffected mother and grandfather. In expression studies using transfected COSm6 cells, mutant sulfonylurea receptor 1 (SUR1) protein was expressed on the cell surface but failed to respond to MgADP even in the heterozygous state. mRNA expression in lymphocytes determined by sequencing cDNA clones and quantifying 6FAM-labeled PCR products found that although the healthy mother predominantly expressed the normal transcript, her affected daughter, carrying the same mutant allele, primarily transcribed the mutant. The methylation pattern of the imprinting control region of chromosome 11p15.5 and ABCC8 promoter was similar for all family members. In conclusion, differences in transcript expression may determine the clinical phenotype of CHI in this maternally inherited dominant mutation. The use of peripheral lymphocytes as a peripheral window to the β-cell transcription profile can serve in resolving β-cell phenotypes. The severe, dominant-negative nature of the 1508insAS mutation suggests that it affects the functional stoichiometry of SUR1-regulated gating of KATP channels.
doi:10.2337/db11-0984
PMCID: PMC3237658  PMID: 22106158
9.  Parental Expressivity and Parenting Styles in Chinese Families: Prospective and Unique Relations to Children’s Psychological Adjustment 
Parenting, science and practice  2011;11(4):288-307.
SYNOPSIS
Objectives
Parents from different cultures differ in how frequently they express emotions. However, the generalizability of the relations between parental expressivity and child adjustment in non-Western cultures has not been extensively studied. The goal of the present study was to investigate prospective relations between parental expressivity within the family (positive, negative dominant, and negative submissive expressivity) and Chinese children’s psychological adjustment, above and beyond parenting styles.
Design
The study used two waves (3.8 years apart) of longitudinal data from a sample (n= 425) of children in Beijing (mean ages = 7.7 years at T1 and 11.6 years at T2). Parental expressivity and parenting styles were self-reported. To reduce the potential measurement overlap, items that tap parental expression of emotions toward the child were removed from the parenting style measure. Children’s adjustment was measured with parents’, teachers’, and peers’ or children’s reports.
Results
Consistent with findings with European American samples, parental negative dominant expressivity uniquely and positively predicted Chinese children’s externalizing problems controlling for prior externalizing problems, parenting styles, and family SES. Neither parental expressivity nor parenting styles uniquely predicted social competence.
Conclusions
Despite previously reported cultural differences in the mean levels of parental expressivity, some of the socialization functions of parental expressivity found in Western countries can be generalized to Chinese families. Although parental expressivity and parenting styles are related constructs, their unique relations to child’s adjustment suggest that they should be examined as distinct processes.
doi:10.1080/15295192.2011.613725
PMCID: PMC3513915  PMID: 23226715
10.  Left Atrial and Right Atrial Deformation in Patients with Coronary Artery Disease: A Velocity Vector Imaging-Based Study 
PLoS ONE  2012;7(12):e51204.
Background
Impaired left ventricular (LV) function has been shown by strain rate (SR) imaging in patients with coronary artery disease (CAD). Our aim was to investigate global and regional, systolic and diastolic left atrial (LA) and right atrial (RA) longitudinal deformation in CAD using velocity vector imaging.
Methods
Echocardiographic and velocity vector imaging studies were performed in 20 patients with mild CAD, 40 patients with severe CAD and 25 controls. Maximal atrial volume, peak atrial longitudinal strain (εs) and SR during LV systole (SRs), SR during early LV filling (SRe) and late LV filling (SRa) were measured. Longitudinal strain during atrial contraction (εa) was obtained at the onset of P-wave on electrocardiography, and εa/εs was calculated.
Results
Longitudinal peak εs and SRs of LA showed decreased trend among CAD patients. The global and lateral LA SRe were prominently lower, while RA εa, SRa and εa/εs were prominently higher in 2 CAD groups than control group (P value <0.05). As compared with controls and patients with other single-vessel disease, LA SRa and εa/εs ratio were significantly increased among patients with exclusively left anterior descending coronary artery (LAD) stenosis (SRa 1.14±0.38 s−1, 1.10±0.41 s−1, 1.45±0.46 s−1, P value<0.05; εa/εs 0.44±0.11, 0.44±0.20, 0.57±0.12, P value<0.01).
Conclusions
Apparently decreased SRe of LA and increased εa, SRa and εa/εs of RA were found in CAD patients with preserved LVEF and E/E' in gray zone. SRa and εa/εs of LA were found to significantly increase in those with LAD stenosis.
doi:10.1371/journal.pone.0051204
PMCID: PMC3552395  PMID: 23349657
12.  Bioreducible and acid-labile poly(amido amine)s for efficient gene delivery 
Intracellular processes, including endosomal escape and intracellular release, are efficiency-determining steps in achieving successful gene delivery. It has been found that the presence of acid-labile units in polymers can facilitate endosomal escape and that the presence of reducible units in polymers can lead to intracellular release. In this study, poly(amido amine)s with both bioreducible and acid-labile properties were synthesized to improve gene delivery compared with single-responsive carriers. Transfection and cytotoxicity were evaluated in three cell lines. The complexes of DNA with dual-responsive polymers showed higher gene transfection efficiency than single-responsive polymers and polyethylenimine. At the same time, these polymers were tens of times less cytotoxic than polyethylenimine. Therefore, a polymer that is both reducible and acid-labile is a promising material for efficient and biocompatible gene delivery.
doi:10.2147/IJN.S37334
PMCID: PMC3511192  PMID: 23209367
reducible; acid labile; gene delivery; dual-responsive; endosomal escape; intracellular release
13.  Dnt1 acts as a mitotic inhibitor of the spindle checkpoint protein dma1 in fission yeast 
Molecular Biology of the Cell  2012;23(17):3348-3356.
The interaction between Dma1 and Dnt1 in fission yeast is characterized. The results show that, similar to its homologue Chfr in higher eukaryotes, Dma1 in fission yeast can also affect factors required for microtubule nucleation and spindle formation at early mitosis.
The Schizosaccharomyces pombe checkpoint protein Dma1 couples mitotic progression with cytokinesis and is important in delaying mitotic exit and cytokinesis when kinetochores are not properly attached to the mitotic spindle. Dma1 is a ubiquitin ligase and potential functional relative of the human tumor suppressor Chfr. Dma1 delays mitotic exit and cytokinesis by ubiquitinating a scaffold protein (Sid4) of the septation initiation network, which, in turn, antagonizes the ability of the Polo-like kinase Plo1 to promote cell division. Here we identify Dnt1 as a Dma1-binding protein. Several lines of evidence indicate that Dnt1 inhibits Dma1 function during metaphase. First, Dnt1 interacts preferentially with Dma1 during metaphase. Second, Dma1 ubiquitin ligase activity and Sid4 ubiquitination are elevated in dnt1∆ cells. Third, the enhanced mitotic defects in dnt1Δ plo1 double mutants are partially rescued by deletion of dma1+, suggesting that the defects in dnt1∆ plo1 double mutants are attributable to excess Dma1 activity. Taken together, these data show that Dnt1 acts to restrain Dma1 activity in early mitosis to allow normal mitotic progression.
doi:10.1091/mbc.E11-12-1020
PMCID: PMC3431938  PMID: 22809626
14.  Effects of preservation time on proliferative potential of human limbal stem/progenitor cells 
AIM
To determine the proliferative potential and the maintenance of stem cell activity in stored human limbal tissues, and correlate this with the preservation time, cell viability and the expression of stem cell markers.
METHODS
Thirty limbal rims were split into 4 parts and stored in corneal preservation medium at 4°C for 0, 1, 4, or 7 days. The limbal stem cell and mitotic markers P63, CK19, proliferating cell nuclear antigen (PCNA), and Ki67 were determined by immunohistochemical staining. The proliferative potential of limbal epithelial cells was assessed by cell viability, the ability of generating stratified epithelium, and colony forming assay.
RESULTS
The stored tissues maintained limbal stratified structure to 7 days and exhibited comparable expression level of stem cell and mitotic markers. The proportion of viable cells decreased with the prolonged preservation time, while colony forming efficiency decreased from the 1st day and disappeared at the 4th day. When inoculated on amniotic membrane, the cells preserved for 1 day formed a stratified epithelium, while the cells from 4 days' preservation formed a discontinuous layer.
CONCLUSION
The colony forming efficiency of limbal epithelial stem/progenitor cells decreased rapidly with the increasing preservation time, while the expression level of markers and capacity of forming epithelial monolayer on amniotic membrane decreased gradually. The limbal epithelial stem cells lost their function earlier than the lost expression level of stem cell markers. This may help us to better choose the appropriate preservation grafts for future limbal stem cell transplantation.
doi:10.3980/j.issn.2222-3959.2012.05.02
PMCID: PMC3484704  PMID: 23166863
limbal epithelial cells; proliferative potential; colony forming efficiency; preservation time
15.  Can EGFR-TKIs be used in first line treatment for advanced non-small cell lung cancer based on selection according to clinical factors ? -- A literature-based meta-analysis 
Background
In the first line treatment of non-small cell lung cancer (NSCLC), several clinical trials have shown that not all NSCLC patients can benefit from treatment with tyrosine kinase inhibitors (TKIs) than receiving chemotherapy. Some trials treated patients with TKI according to their clinical characteristics. A few studies only chose patients with an epidermal grouth factor receptor (EGFR) mutation for TKI therapy. We aimed to determine whether patients could be treated with TKIs based on clinical factors in the first-line setting.
Methods
We performed a meta-analysis of randomized trials involving patients with advanced NSCLC treated with chemotherapy or TKIs by different selections. Efficacy outcomes of interest were the objective response rate (ORR), progression-free survival (PFS) and the overall survival (OS) of each treatment arm.
Results
Four trials enrolled unselected patients, and two trials selected East Asian patients using the clinical factors of gender and smoking history. Five trials chose patients with an EGFR mutation who were randomized for treatment with TKI or chemotherapy. For unselected patients, the risk ratio (RR) of the ORR was 3.52, the hazard ratio (HR) of the PFS was 1.29 and the HR of the OS was 1.35. For the clinically selected patients, the RR of the ORR was 0.64. The HRs of the PFS and OS were 0.83 and 0.92, respectively. The ORR and PFS were better for TKIs than for chemotherapy in patients with an EGFR mutation. The ORR was 0.47, and the HRs of the PFS and OS were 0.36 and 1.00, respectively.
Conclusions
Advanced NSCLC patients with an EGFR mutation benefit most from TKIs. EGFR-TKI treatment is justified for patients with unknown EGFR status,and those who cannot tolerate chemotherapy owing to age, poor performance status (PS) or other medical conditions, when selected according to clinical factors in the first-line setting.
doi:10.1186/1756-8722-5-62
PMCID: PMC3507915  PMID: 23050865
Non-small cell lung cancer; Target therapy; Chemotherapy; Meta-analysis
16.  Differentiation in MALDI-TOF MS and FTIR spectra between two closely related species Acidovorax oryzae and Acidovorax citrulli 
BMC Microbiology  2012;12:182.
Background
Two important plant pathogenic bacteria Acidovorax oryzae and Acidovorax citrulli are closely related and often not easy to be differentiated from each other, which often resulted in a false identification between them based on traditional methods such as carbon source utilization profile, fatty acid methyl esters, and ELISA detection tests. MALDI-TOF MS and Fourier transform infrared (FTIR) spectra have recently been successfully applied in bacterial identification and classification, which provide an alternate method for differentiating the two species.
Results
Characterization and comparison of the 10 A. oryzae strains and 10 A. citrulli strains were performed based on traditional bacteriological methods, MALDI-TOF MS, and FTIR spectroscopy. Our results showed that the identity of the two closely related plant pathogenic bacteria A. oryzae and A. citrulli was able to be confirmed by both pathogenicity tests and species-specific PCR, but the two species were difficult to be differentiated based on Biolog and FAME profile as well as 16 S rRNA sequence analysis. However, there were significant differences in MALDI-TOF MS and FTIR spectra between the two species of Acidovorax. MALDI-TOF MS revealed that 22 and 18 peaks were specific to A. oryzae and A. citrulli, respectively, while FTIR spectra of the two species of Acidovorax have the specific peaks at 1738, 1311, 1128, 1078, 989 cm-1 and at 1337, 968, 933, 916, 786 cm-1, respectively.
Conclusions
This study indicated that MALDI-TOF MS and FTIR spectra may give a new strategy for rapid bacterial identification and differentiation of the two closely related species of Acidovorax.
doi:10.1186/1471-2180-12-182
PMCID: PMC3438124  PMID: 22900823
17.  Delivery of a Peptide Radiopharmaceutical to Brain with an IgG-Avidin Fusion Protein 
Bioconjugate chemistry  2011;22(8):1611-1618.
The genetic engineering, host cell expression, purity, identity, and in vivo brain drug targeting properties are described for a new IgG-fusion protein, designated the cTfRMAb-AV fusion protein. Avidin (AV) is fused to the carboxyl terminus of the heavy chain of the genetically engineered chimeric monoclonal antibody (MAb) against the mouse transferrin receptor (TfR). The TfRMAb binds the endogenous TfR on the blood-brain barrier (BBB), which triggers transport into brain from blood. The cTfRMAb-AV fusion protein is produced in stably transfected Chinese hamster ovary cells, which are grown in serum free medium under conditions of biotin starvation. Following affinity purification, the purity and identity of the cTfRMAb-AV fusion protein was verified by electrophoresis and Western blotting. The affinity of the cTfRMAb for the murine TfR is high, KI = 4.6±0.5 nM, despite fusion of avidin to the antibody heavy chain. The model peptide radiopharmaceutical used in this study is the Aβ1-40 amyloid peptide of Alzheimer’s disease (AD), which in a brain-penetrating form could be used to image the amyloid plaque in brain in AD. The BBB transport and brain uptake of the [125I]-Aβ1-40 peptide was measured in mice injected intravenously (IV) with the peptide either free or conjugated to the cTfRMAb-AV fusion protein. The brain uptake of the free Aβ1-40 peptide was very low, 0.1 % of injected dose (ID)/gram brain following IV injection, and is comparable to the brain uptake of a brain blood volume marker. However, the brain uptake of the Aβ1-40 peptide was high, 2.1 ± 0.2 % ID/gram brain, following attachment of the biotinylated peptide to the cTfRMAb-AV fusion protein. Capillary depletion analysis showed the peptide penetrated the brain parenchyma from blood. The cTfRMAb-AV fusion protein is a new drug delivery system that can target to mouse brain mono-biotinylated peptide or antisense radiopharmaceuticals.
doi:10.1021/bc200174x
PMCID: PMC3157551  PMID: 21707084
18.  Expression in CHO Cells and Pharmacokinetics and Brain Uptake in the Rhesus Monkey of an IgG-Iduronate-2-Sulfatase Fusion Protein 
Biotechnology and bioengineering  2011;108(8):1954-1964.
Sulfatases are potential therapeutic biopharmaceuticals, as mutations in sulfatase genes leads to inherited disease. Mucopolysaccharidosis (MPS) Type II is caused by mutations in the lysosomal enzyme, iduronate 2-sulfatase (IDS). MPS-II affects the brain and enzyme replacement therapy is ineffective for the brain, because IDS does not cross the blood-brain barrier (BBB). To deliver IDS across the human BBB, the sulfatase has been re-engineered as an IgG-sulfatase fusion protein with a genetically engineered monoclonal antibody (MAb) against the human insulin receptor (HIR). The HIRMAb part of the HIRMAb-IDS fusion protein acts as a molecular Trojan horse to ferry the fused IDS across the BBB. Chinese hamster ovary (CHO) cell were stably transfected to produce the HIRMAb-IDS fusion protein. The fusion protein was triaged to the lysosomal compartment of MPS-II fibroblasts based on confocal microscopy, and 300 ng/mL medium concentrations normalized IDS enzyme activity in the cells. The HIRMAb-IDS fusion protein was tritiated and injected intravenously into the adult Rhesus monkey at a low dose of 0.1 mg/kg. The IDS enzyme activity in plasma was elevated 10-fold above the endogenous level, and therapeutic plasma concentrations were generated in vivo. The uptake of the HIRMAb-IDS fusion protein in the brain was sufficiently high to produce therapeutic concentrations of IDS in the brain following IV administration of the fusion protein.
doi:10.1002/bit.23118
PMCID: PMC3117053  PMID: 21351076
iduronate 2-sulfatase; monoclonal antibody; drug delivery; insulin receptor; brain
19.  Optimizing the Detection of Lung Cancer Patients Harboring Anaplastic Lymphoma Kinase (ALK) Gene Rearrangements Potentially Suitable for ALK Inhibitor Treatment 
Clinical Cancer Research  2010;16(22):5581-5590.
Purpose
Anaplastic lymphoma kinase (ALK) rearrangements, associated with sensitivity to an experimental ALK/MET inhibitor, occur in 3% to 5% of non-small cell lung cancers. Intratumoral fluorescence in situ hybridization (FISH) heterogeneity has been reported. We explored the heterogeneity basis, the requirements for accurately determining ALK FISH positivity, and the effect of enriching the tested population using clinical and molecular factors.
Experimental Design
Lung cancer patients were screened by ALK and MET FISH and for EGFR and KRAS mutations.
Results
Thirteen ALK-positive cases were identified from 73 screened patients. Gene copy number increases occurred together with classic rearrangements. All positive cases were adenocarcinomas, 12 were EGFR/KRAS wild-type, and 1 had a coexistent EGFR exon 20 mutation. No association with MET amplification occurred. ALK positivity was associated with <10-pack-year smoking status (P = 0.0004). Among adenocarcinomas, without KRAS or EGFR mutations, with <10-pack-year history, 44.8% of cases were ALK positive. ALK FISH positivity was heterogeneous, but mean values in tumor areas from ALK-positive patients (54% of cells; range, 22-87%) were significantly higher than in adjacent normal tissue or tumor/ normal areas from ALK-negative patients (mean, 5-7%). Contiguous sliding field analyses showed diffuse heterogeneity without evidence of focal ALK rearrangements. One hundred percent sensitivity and specificity occurred when four or more fields (~60 cells) were counted.
Conclusions
Intratumoral ALK FISH heterogeneity reflects technique, not biology. The clinical activity of ALK/MET inhibitors in ALK-positive patients probably reflects ALK, but not MET, activity. Prescreening by histology, EGFR/KRAS mutations, and smoking status dramatically increases the ALK-positive hit rate compared with unselected series.
doi:10.1158/1078-0432.CCR-10-0851
PMCID: PMC3395226  PMID: 21062932
20.  MicroRNA 107 Partly Inhibits Endothelial Progenitor Cells Differentiation via HIF-1β 
PLoS ONE  2012;7(7):e40323.
Endothelial progenitor cells (EPCs) play an important role in tissue repair after ischemic heart disease. In particular, the recovery of endothelial function is reliant on the ability and rate of EPCs differentiate into mature endothelial cells. The present study evaluated the effect of microRNA 107 (miR-107) on the mechanism of EPCs differentiation. EPCs were isolated from rats' bone marrow and miR-107 expression of EPCs in hypoxic and normoxic conditions were measured by real-time qualitative PCR. CD31 was analyzed by flow cytometry and eNOS was examined by real-time qualitative PCR and western blotting and these were used as markers of EPC differentiation. In order to reveal the mechanism, we used miR107 inhibitor and lentiviral vector expressing a short hairpin RNA (shRNA) that targets miR-107 and hypoxia-inducible factor-1 β (HIF-1β) to alter miR107 and HIF-1β expression. MiR-107 expression were increased in EPCs under hypoxic conditions. Up-regulation of miR-107 partly suppressed the EPCs differentiation induced in hypoxia, while down-regulation of miR-107 promoted EPC differentiation. HIF-1β was the target. This study indicated that miR-107 was up-regulated in hypoxia to prevent EPCs differentiation via its target HIF-1β. The physiological mechanisms of miR-107 must be evaluated if it is to be used as a potential anti-ischemia therapeutic regime.
doi:10.1371/journal.pone.0040323
PMCID: PMC3391260  PMID: 22792280
21.  Identification of Enriched Driver Gene Alterations in Subgroups of Non-Small Cell Lung Cancer Patients Based on Histology and Smoking Status 
PLoS ONE  2012;7(6):e40109.
Background
Appropriate patient selection is needed for targeted therapies that are efficacious only in patients with specific genetic alterations. We aimed to define subgroups of patients with candidate driver genes in patients with non-small cell lung cancer.
Methods
Patients with primary lung cancer who underwent clinical genetic tests at Guangdong General Hospital were enrolled. Driver genes were detected by sequencing, high-resolution melt analysis, qPCR, or multiple PCR and RACE methods.
Results
524 patients were enrolled in this study, and the differences in driver gene alterations among subgroups were analyzed based on histology and smoking status. In a subgroup of non-smokers with adenocarcinoma, EGFR was the most frequently altered gene, with a mutation rate of 49.8%, followed by EML4-ALK (9.3%), PTEN (9.1%), PIK3CA (5.2%), c-Met (4.8%), KRAS (4.5%), STK11 (2.7%), and BRAF (1.9%). The three most frequently altered genes in a subgroup of smokers with adenocarcinoma were EGFR (22.0%), STK11 (19.0%), and KRAS (12.0%). We only found EGFR (8.0%), c-Met (2.8%), and PIK3CA (2.6%) alterations in the non-smoker with squamous cell carcinoma (SCC) subgroup. PTEN (16.1%), STK11 (8.3%), and PIK3CA (7.2%) were the three most frequently enriched genes in smokers with SCC. DDR2 and FGFR2 only presented in smokers with SCC (4.4% and 2.2%, respectively). Among these four subgroups, the differences in EGFR, KRAS, and PTEN mutations were statistically significant.
Conclusion
The distinct features of driver gene alterations in different subgroups based on histology and smoking status were helpful in defining patients for future clinical trials that target these genes. This study also suggests that we may consider patients with infrequent alterations of driver genes as having rare or orphan diseases that should be managed with special molecularly targeted therapies.
doi:10.1371/journal.pone.0040109
PMCID: PMC3387024  PMID: 22768234
22.  Diazoxide-Unresponsive Congenital Hyperinsulinism in Children With Dominant Mutations of the β-Cell Sulfonylurea Receptor SUR1 
Diabetes  2011;60(6):1797-1804.
OBJECTIVE
Congenital hyperinsulinemic hypoglycemia is a group of genetic disorders of insulin secretion most commonly associated with inactivating mutations of the β-cell ATP-sensitive K+ channel (KATP channel) genes ABCC8 (SUR1) and KCNJ11 (Kir6.2). Recessive mutations of these genes cause hyperinsulinism that is unresponsive to treatment with diazoxide, a channel agonist. Dominant KATP mutations have been associated with diazoxide-responsive disease. We hypothesized that some medically uncontrollable cases with only one KATP mutation might have dominant, diazoxide-unresponsive disease.
RESEARCH DESIGN AND METHODS
Mutations of the KATP genes were identified by sequencing genomic DNA. Effects of mutations on KATP channel function in vitro were studied by expression in COSm6 cells.
RESULTS
In 15 families with diazoxide-unresponsive diffuse hyperinsulism, we found 17 patients with a monoallelic missense mutation of SUR1. Nine probands had de novo mutations, two had an affected sibling or parent, and four had an asymptomatic carrier parent. Of the 13 different mutations, 12 were novel. Expression of mutations revealed normal trafficking of channels but severely impaired responses to diazoxide or MgADP. Responses were significantly lower compared with nine SUR1 mutations associated with dominant, diazoxide-responsive hyperinsulinism.
CONCLUSIONS
These results demonstrate that some dominant mutations of SUR1 can cause diazoxide-unresponsive hyperinsulinism. In vitro expression studies may be helpful in distinguishing such mutations from dominant mutations of SUR1 associated with diazoxide-responsive disease.
doi:10.2337/db10-1631
PMCID: PMC3114386  PMID: 21536946
23.  Nedaplatin/Gemcitabine Versus Carboplatin/Gemcitabine in Treatment of Advanced Non-small Cell Lung Cancer: A Randomized Clinical Trial 
Objective
To evaluate the efficacy and safety of nedaplatin/gemcitabine (NG) and carboplatin/gemcitabine (CG) in the management of untreated advanced non-small cell lung cancer (NSCLC).
Methods
Sixty-two patients with previously untreated advanced NSCLC were recruited between June 2006 and November 2007. Subjects were randomly assigned to the NG arm (n=30) and the CG arm (n=32). Only patients (24 and 25 in the NG and CG arms, respectively) who completed ≥2 chemotherapy cycles were included in the data analysis. The primary outcome measure was the objective response rate (ORR). The secondary outcome measures included progression-free survival (PFS), overall survival (OS) and adverse events.
Results
There were no statistically significant differences in the efficacy measures (ORR, P=0.305; median PFS, P=0.198; median OS, P=0.961) or in the major adverse events (grade 3/4 neutropenia, P=0.666; grade 3/4 anemia, P=0.263; grade 3/4 thrombocytopenia, P=0.212) between the two treatment arms. However, there was a trend towards higher ORR (37.5% vs. 24.0%), longer PFS (6.0 vs. 5.0 months), and less adverse events in the NG arm.
Conclusion
NG regimen seems to be superior over CG regimen for advance NSCLS, but further investigation is needed to validate this superiority.
doi:10.1007/s11670-012-0097-8
PMCID: PMC3555264  PMID: 23359648
Non-small cell lung cancer; Chemotherapy; Nedaplatin; Carboplatin; Gemcitabine; Squamous cell carcinoma
24.  Transposable-Element Associated Small RNAs in Bombyx mori Genome 
PLoS ONE  2012;7(5):e36599.
Small RNAs are a group of regulatory RNA molecules that control gene expression at transcriptional or post-transcriptional levels among eukaryotes. The silkworm, Bombyx mori L., genome harbors abundant repetitive sequences derived from families of retrotransposons and transposons, which together constitute almost half of the genome space and provide ample resource for biogenesis of the three major small RNA families. We systematically discovered transposable-element (TE)-associated small RNAs in B. mori genome based on a deep RNA-sequencing strategy and the effort yielded 182, 788 and 4,990 TE-associated small RNAs in the miRNA, siRNA and piRNA species, respectively. Our analysis suggested that the three small RNA species preferentially associate with different TEs to create sequence and functional diversity, and we also show evidence that a Bombyx non-LTR retrotransposon, bm1645, alone contributes to the generation of TE-associated small RNAs in a very significant way. The fact that bm1645-associated small RNAs partially overlap with each other implies a possibility that this element may be modulated by different mechanisms to generate different products with diverse functions. Taken together, these discoveries expand the small RNA pool in B. mori genome and lead to new knowledge on the diversity and functional significance of TE-associated small RNAs.
doi:10.1371/journal.pone.0036599
PMCID: PMC3359762  PMID: 22662121
25.  Exposure to Retinoic Acid in the Neonatal but Not Adult Mouse Results in Synchronous Spermatogenesis1 
Biology of Reproduction  2011;84(5):886-893.
Retinoic acid (RA) is required for germ cell differentiation, the regulation of which gives rise to a constant production of mature sperm. In testes from 3-day postpartum (dpp) RARE-hsplacZ mice, periodic regions positive for beta-galactosidase activity were observed along the length of the seminiferous tubules. Periodicity was abolished by treatment of neonates with exogenous RA at 2 dpp. To assess the consequences, 2-dpp mice were treated with RA, and the long- and short-term effects were assessed. Long-term effects of neonatal RA exposure included a delay in the appearance of advanced germ cells and the absence of a spermatogenic wave (synchronous spermatogenesis) in the adult. In contrast, RA exposure in vitamin A-sufficient adults did not result in synchronous spermatogenesis but rather induced apoptosis in a subset of spermatogonia. Shortly after (24 h) neonates were exposed, altered expression of known germ cell differentiation and the (Stra8, Kit, Sycp3, and Rec8) meiosis markers and an increase in the number of STRA8 and SYCP3 immunopositive cells were observed relative to those of vehicle controls. However, 48 and 72 h after exposure, a significant reduction in the number of STRA8 and SYCP3 immunopositive cells occurred. Immunohistochemical analysis of a marker for apoptosis demonstrated neonatal exposure resulted in increased germ cell apoptosis, as observed in the adult. Additionally, RA exposure resulted in increased Cyp26a1 expression of the RA-degrading enzyme. Thus, while RA treatment of neonatal and adult mice resulted in apoptosis of spermatogonia, synchronous spermatogenesis occurred only after neonatal RA exposure.
Exposure of neonatal but not adult mice to exogenous retinoic acid leads to synchronous spermatogenesis via altered initiation of the spermatogenic wave.
doi:10.1095/biolreprod.110.089755
PMCID: PMC3080418  PMID: 21228214
apoptosis; gametogenesis; germ cell differentiation; retinoic acid; spermatogenesis; testis; vitamin A deficiency

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