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1.  Growth and Nitrogen Uptake Kinetics in Cultured Prorocentrum donghaiense 
PLoS ONE  2014;9(4):e94030.
We compared growth kinetics of Prorocentrum donghaiense cultures on different nitrogen (N) compounds including nitrate (NO3−), ammonium (NH4+), urea, glutamic acid (glu), dialanine (diala) and cyanate. P. donghaiense exhibited standard Monod-type growth kinetics over a range of N concentraions (0.5–500 μmol N L−1 for NO3− and NH4+, 0.5–50 μmol N L−1 for urea, 0.5–100 μmol N L−1 for glu and cyanate, and 0.5–200 μmol N L−1 for diala) for all of the N compounds tested. Cultures grown on glu and urea had the highest maximum growth rates (μm, 1.51±0.06 d−1 and 1.50±0.05 d−1, respectively). However, cultures grown on cyanate, NO3−, and NH4+ had lower half saturation constants (Kμ, 0.28–0.51 μmol N L−1). N uptake kinetics were measured in NO3−-deplete and -replete batch cultures of P. donghaiense. In NO3−-deplete batch cultures, P. donghaiense exhibited Michaelis-Menten type uptake kinetics for NO3−, NH4+, urea and algal amino acids; uptake was saturated at or below 50 μmol N L−1. In NO3−-replete batch cultures, NH4+, urea, and algal amino acid uptake kinetics were similar to those measured in NO3−-deplete batch cultures. Together, our results demonstrate that P. donghaiense can grow well on a variety of N sources, and exhibits similar uptake kinetics under both nutrient replete and deplete conditions. This may be an important factor facilitating their growth during bloom initiation and development in N-enriched estuaries where many algae compete for bioavailable N and the nutrient environment changes as a result of algal growth.
PMCID: PMC3977987  PMID: 24710151
2.  Associations between Two Polymorphisms (FokI and BsmI) of Vitamin D Receptor Gene and Type 1 Diabetes Mellitus in Asian Population: A Meta-Analysis 
PLoS ONE  2014;9(3):e89325.
Vitamin D receptor (VDR) gene polymorphisms are possibly involved in the development of type 1 diabetes mellitus (T1DM). However, the results to date have been inconclusive. We performed a meta-analysis to examine the association between 2 polymorphisms (FokI and BsmI) of the VDR gene and T1DM in the Asian population.
Literature was retrieved from PubMed, Web of Science, CBM, Embase and Chinese databases. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a random or fixed effect model.
In total, 20 papers (BsmI: 13 studies; FokI: 13 studies) were included. In contrast to the FokI polymorphism, the BsmI polymorphism was associated with an increased risk of T1DM in the Asian population (OR = 1.47, 95% CI = 1.13–1.91, P = 0.004 for B vs. b). Upon stratification by regional geography, an increased risk of T1DM in association with the BsmI polymorphism was observed in the East Asian population (OR = 1.97, 95% CI = 1.38–2.83, P<0.001 for B vs. b), whereas the FokI polymorphism was associated with an increased risk of T1DM in the West Asian population (OR = 1.45, 95% CI = 1.12–1.88, P = 0.004 for F vs. f).
Our meta-analysis suggests that the BsmI polymorphism may be a risk factor for susceptibility to T1DM in the East Asian population, and the FokI polymorphism is associated with an increased risk of T1DM in the West Asian population. However, because the study size was limited, further studies are essential to confirm our results.
PMCID: PMC3945782  PMID: 24603699
3.  Effects of experimental conditions on the morphologies, structures and growth modes of pulsed laser-deposited CdS nanoneedles 
CdS nanoneedles with different morphologies, structures, and growth modes have been grown on Ni-coated Si(100) surface under different experimental conditions by pulsed laser deposition method. The effects of catalyst layer, substrate temperature, and laser pulse energy on the growth of the CdS nanoneedles were studied in detail. It was confirmed that the formation of the molten catalyst spheres is the key to the nucleation of the CdS nanoneedles by observing the morphologies of the Ni catalyst thin films annealed at different substrate temperatures. Both the substrate temperature and laser pulse energy strongly affected the growth modes of the CdS nanoneedles. The secondary growth of the smaller nanoneedles on the top of the main nanoneedles was found at appropriate conditions. A group of more completed pictures of the growth modes of the CdS nanoneedles were presented.
PMCID: PMC3941934  PMID: 24559455
CdS nanoneedles; Substrate temperature; Laser pulse energy; Growth mode; 61.46.-w; 61.46.Km; 68.37.Lp
4.  Procedures for Behavioral Experiments in Head-Fixed Mice 
PLoS ONE  2014;9(2):e88678.
The mouse is an increasingly prominent model for the analysis of mammalian neuronal circuits. Neural circuits ultimately have to be probed during behaviors that engage the circuits. Linking circuit dynamics to behavior requires precise control of sensory stimuli and measurement of body movements. Head-fixation has been used for behavioral research, particularly in non-human primates, to facilitate precise stimulus control, behavioral monitoring and neural recording. However, choice-based, perceptual decision tasks by head-fixed mice have only recently been introduced. Training mice relies on motivating mice using water restriction. Here we describe procedures for head-fixation, water restriction and behavioral training for head-fixed mice, with a focus on active, whisker-based tactile behaviors. In these experiments mice had restricted access to water (typically 1 ml/day). After ten days of water restriction, body weight stabilized at approximately 80% of initial weight. At that point mice were trained to discriminate sensory stimuli using operant conditioning. Head-fixed mice reported stimuli by licking in go/no-go tasks and also using a forced choice paradigm using a dual lickport. In some cases mice learned to discriminate sensory stimuli in a few trials within the first behavioral session. Delay epochs lasting a second or more were used to separate sensation (e.g. tactile exploration) and action (i.e. licking). Mice performed a variety of perceptual decision tasks with high performance for hundreds of trials per behavioral session. Up to four months of continuous water restriction showed no adverse health effects. Behavioral performance correlated with the degree of water restriction, supporting the importance of controlling access to water. These behavioral paradigms can be combined with cellular resolution imaging, random access photostimulation, and whole cell recordings.
PMCID: PMC3919818  PMID: 24520413
5.  Potassium channels control the interaction between active dendritic integration compartments in layer 5 cortical pyramidal neurons 
Neuron  2013;79(3):10.1016/j.neuron.2013.06.005.
Active dendritic synaptic integration enhances the computational power of neurons. Such nonlinear processing generates an object-localization signal in the apical dendritic tuft of layer 5B cortical pyramidal neurons during sensory-motor behaviour. Here we employ electrophysiological and optical approaches in brain-slices and behaving animals to investigate how excitatory synaptic input to this distal dendritic compartment influences neuronal output. We find that active dendritic integration throughout the apical dendritic tuft is highly compartmentalized by voltage-gated potassium (KV) channels. A high-density of both transient and sustained KV channels was observed in all apical dendritic compartments. These channels potently regulated the interaction between apical dendritic tuft, trunk, and axo-somatic integration zones to control neuronal output in vitro as well as the engagement of dendritic nonlinear processing in vivo during sensory-motor behaviour. Thus, KV channels dynamically tune the interaction between active dendritic integration compartments in layer 5B pyramidal neurons to shape behaviourally relevant neuronal computations.
PMCID: PMC3847879  PMID: 23931999
6.  Extended photoresponse and multi-band luminescence of ZnO/ZnSe core/shell nanorods 
Aligned ZnO/ZnSe core/shell nanorods (NRs) with type-II energy band alignment were fabricated by pulsed laser deposition of ZnSe on the surfaces of hydrothermally grown ZnO NRs. The obtained ZnO/ZnSe core/shell NRs are composed of wurtzite ZnO cores and zinc blende ZnSe shells. The bare ZnO NRs are capable of emitting strong ultraviolet (UV) near band edge (NBE) emission at 325-nm light excitation, while the ZnSe shells greatly suppress the emission from the ZnO cores. High-temperature processing results in an improvement in the structures of the ZnO cores and the ZnSe shells and significant changes in the optical properties of ZnO/ZnSe core/shell NRs. The fabricated ZnO/ZnSe core/shell NRs show optical properties corresponding to the two excitonic band gaps of wurtzite ZnO and zinc blende ZnSe and the effective band gap between the conduction band minimum of ZnO and the valence band maximum ZnSe. An extended photoresponse much wider than those of the constituting ZnO and ZnSe and a multi-band photoluminescence including the UV NBE emission of ZnO and the blue NBE emission of ZnSe are observed.
PMCID: PMC3896834  PMID: 24428949
ZnO/ZnSe core/shell nanorods; Type-II heterojunction; Photoresponse; Near band edge emission; Suppression of luminescence
7.  Nasal Embryonic LHRH Factor (NELF) Mutations in Patients with Normosmic Hypogonadotropic Hypogonadism and Kallmann Syndrome 
Fertility and sterility  2011;95(5):1613-20.e1-7.
Study Objective
To determine if mutations in NELF, a gene isolated from migratory GnRH neurons, cause normosmic idiopathic hypogonadotropic hypogonadism (IHH) and Kallmann syndrome (KS)
Molecular analysis correlated with phenotype
Academic medical center
168 IHH/KS patients along with unrelated controls were studied for NELF mutations.
NELF coding regions/splice junctions were subjected to PCR-based DNA sequencing, Eleven additional IHH/KS genes were sequenced in three patients with NELF mutations.
Main Outcome Measure
Mutations were confirmed by SIFT, RT-PCR, and western blot analysis.
Three novel NELF mutations absent in 372-ethnically matched controls were identified in 3/168(1.8%) IHH/KS patients. One IHH patient had compound heterozygous NELF mutations (c.629-21C>G and c.629-23G>C); and he did not have mutations in 11 other known IHH/KS genes. Two unrelated KS patients had heterozygous NELF mutations and mutation in a second gene: NELF/KAL1 (c.757G>A; p.Ala253Thr of NELF and c.488_490delGTT; p.Cys163del of KAL1) and NELF/TACR3 (c. 1160-13C>T of NELF and c.824G>A; p.Trp275X of TACR3). In vitro evidence of these NELF mutations included reduced protein expression and splicing defects.
Our findings suggest that NELF is associated with normosmic IHH and KS, either singly or in combination with a mutation in another gene.
PMCID: PMC3888818  PMID: 21300340
Nasal embryonic LHRH factor; hypogonadotropic hypogonadism; Kallmann syndrome; gonadotropin-releasing hormone (GnRH); GnRH neuron migration
8.  Decreased Activities of Apolipoprotein M Promoter Are Associated with the Susceptibility to Coronary Artery Diseases 
The present study investigated the correlation among genetic polymorphisms of the proximal promoter region of apolipoprotein M (apoM) gene, the polymorphisms in relation to apoM expressions and the susceptibility to coronary artery diseases (CAD) in a Han Chinese population. Four common polymorphic sites, i.e., T-1628G, C-1065A, T-855C and T-778C, were confirmed, and a new deletion mutation C-724del was found, in 206 CAD patients and 209 non-CAD patients using direct DNA sequencing analyses. Occurrences of alleles T-1628G, T-855C and C-724del were significantly higher in CAD patients compared to non-CAD patients. Moreover we examined all these polymorphisms in relation to apoM expression by applying luciferase reporter assay. It demonstrated that constructs -855C and 724del showed obvious decreased luciferase activities, i.e., (0.93±0.15 vs. 2.11±0.15; P=0.012) and (1.13±0.25 vs. 2.11±0.15; P=0.009) respectively, which indicates these two polymorphisms could confer decreased apoM expressions. Meanwhile the occurrences of these two SNP were also significantly higher in the CAD patients than in non-CAD patients. It is therefore reasonable to speculate that down-regulated apoM expressions in relation to these polymorphisms may affect HDL and cholesterol metabolism in vivo and further influence the susceptibility to CAD, although the underlying mechanisms need further investigation.
PMCID: PMC3936031  PMID: 24578614
apolipoprotein M; promoter; polymorphism; expression; coronary artery diseases
9.  Upregulated TIMP-1 correlates with poor prognosis of laryngeal squamous cell carcinoma 
The tissue inhibitor of metalloproteinase-1 (TIMP-1) is an endogenous inhibitor of matrix metalloproteinases and potential biomarker of various types of human cancers. However, the association between TIMP-1 expression and the clinical features of laryngeal squamous cell carcinoma (LSCC) is barely investigated. In this study, one-step quantitative reverse transcription-polymerase chain reaction and immunohistochemical staining with tissue microarrays were employed to evaluate the relationship between TIMP-1 expression and the clinicopathological characteristics of LSCC. Results showed that the TIMP-1 mRNA and protein expression levels were significantly higher in LSCC than in the corresponding non-cancerous tissues (p<0.05). TIMP-1 protein expression in LSCC was associated with tumor differentiation (p=0.012) and overall survival (p=0.043). Kaplan-Meier method and Cox multi-factor analysis suggested that high TIMP-1 expression (p=0.008) and positive lymph node metastasis (p=0.029) were significantly associated with the poor survival of patients with LSCC. These data indicated that TIMP-1 may be identified as a prognostic marker of LSCC.
PMCID: PMC3885479  PMID: 24427345
TIMP-1; LSCC; qPCR; immunohistochemistry; prognosis
10.  2-(1-Benzo­thio­phen-2-yl)-4H-1,3,4-oxa­diazin-5(6H)-one 
In the title compound, C11H8N2O2S, the oxadiazinone ring is nearly planar [maximum deviation = 0.016 (4) Å], and is approximately coplanar with the benzo­thio­phene ring system [dihedral angle = 3.1 (5)°]. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds, forming chains running along the b-axis direction.
PMCID: PMC3914084  PMID: 24526987
11.  Signature of Circulating MicroRNAs as Potential Biomarkers in Vulnerable Coronary Artery Disease 
PLoS ONE  2013;8(12):e80738.
MicroRNAs (miRNAs) play important roles in the pathogenesis of cardiovascular diseases. Circulating miRNAs were recently identified as biomarkers for various physiological and pathological conditions. In this study, we aimed to identify the circulating miRNA fingerprint of vulnerable coronary artery disease (CAD) and explore its potential as a novel biomarker for this disease.
Methods and Results
The Taqman low-density miRNA array and coexpression network analyses were used to identify distinct miRNA expression profiles in the plasma of patients with typical unstable angina (UA) and angiographically documented CAD (UA group, n = 13) compared to individuals with non-cardiac chest pain (control group, n = 13). Significantly elevated expression levels of miR-106b/25 cluster, miR-17/92a cluster, miR-21/590-5p family, miR-126*, and miR-451 were observed in UA patients compared to controls. These findings were validated by real-time PCR in another 45 UA patients, 31 stable angina patients, and 37 controls. In addition, miR-106b, miR-25, miR-92a, miR-21, miR-590-5p, miR-126* and miR-451 were upregulated in microparticles (MPs) isolated from the plasma of UA patients (n = 5) compared to controls (n = 5). Using flow cytometry and immunolabeling, we further found that Annexin V+ MPs were increased in the plasma samples of UA patients compared to controls, and the majority of the increased MPs in plasma were shown to be Annexin V+ CD31+ MPs. The findings suggest that Annexin V+ CD31+ MPs may contribute to the elevated expression of the selected miRNAs in the circulation of patients with vulnerable CAD.
The circulating miRNA signature, consisting of the miR-106b/25 cluster, miR-17/92a cluster, miR-21/590-5p family, miR-126* and miR-451, may be used as a novel biomarker for vulnerable CAD.
Trial Registration
Chinese Clinical Trial Register, ChiCTR-OCH-12002349.
PMCID: PMC3855151  PMID: 24339880
12.  Dimethyl 3,3′-(phenyl­methyl­ene)bis­(1H-indole-2-carboxyl­ate) 
In the title compound, C27H22N2O4, the two indole ring systems are approximately perpendicular to each other, with a dihedral angle of 84.5 (5)° between their planes; the benzene ring is twisted with respect to the two indole ring systems at angles of 78.5 (5) and 86.5 (3)°. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds, weak C—H⋯O and C—H⋯N hydrogen bonds, and C—H⋯π inter­actions into a three-dimensional supra­molecular architecture.
PMCID: PMC3790385  PMID: 24098207
13.  A rare case of bilateral sequential spermatocytic seminoma 
Spermatocytic seminoma (SS) is a rare testicular neoplasm characterized by a palpable, painless, slowly enlarging mass in the testis. Even more rare is a synchronous bilateral presentation. Only eight cases of bilateral SS have been reported in the literature, of which three cases were present with synchronous testis enlargement, and five were sequential. Here, we report an additional case of synchronous bilateral SS and present a comprehensive relevant literature review concerning clinical features, histopathology, and treatment.
PMCID: PMC3751534  PMID: 23915031
Spermatocytic seminoma; Fine-needle aspiration cytology; Bilateral spermatocytic seminoma; Testicular cancer
14.  Transarterial Treatment of Direct Carotid Cavernous Fistulas with the Assistance of Undetachable Balloons 
ISRN Neurology  2013;2013:152076.
Directed carotid cavernous fistula means high blood flow shunts between the internal carotid artery and the cavernous sinus. Obstructing the abnormal shunt between the internal carotid artery and the cavernous sinus while preserving the internal carotid artery is the key role in fistula treatment. Transarterial balloon embolization is currently the gold standard treatment for most of the carotid cavernous fistulas. But there are still some technical difficulties in the use of detachable balloon to treat carotid cavernous fistulas. Here, we describe undetachable balloon-assisted technique in the embolization of three patients who got complete immediate occlusion of the shunt and preserved the internal carotid artery at the same time.
PMCID: PMC3659488  PMID: 23738142
15.  Aft2, a Novel Transcription Regulator, Is Required for Iron Metabolism, Oxidative Stress, Surface Adhesion and Hyphal Development in Candida albicans 
PLoS ONE  2013;8(4):e62367.
Morphological transition and iron metabolism are closely relevant to Candida albicans pathogenicity and virulence. In our previous study, we demonstrated that C. albicans Aft2 plays an important role in ferric reductase activity and virulence. Here, we further explored the roles of C. albicans Aft2 in numerous cellular processes. We found that C. albicans Aft2 exhibited an important role in iron metabolism through bi-directional regulation effects on iron-regulon expression. Deletion of AFT2 reduced cellular iron accumulation under iron-deficient conditions. Furthermore, both reactive oxygen species (ROS) generation and superoxide dismutase (SOD) activity were remarkably increased in the aft2Δ/Δ mutant, which were thought to be responsible for the defective responses to oxidative stress. However, we found that over-expression of C. albicans AFT2 under the regulation of the strong PGK1 promoter could not effectively rescue Saccharomyces cerevisiae aft1Δ mutant defects in some cellular processes, such as cell-wall assembly, ion homeostasis and alkaline resistance, suggesting a possibility that C. albicans Aft2 weakened its functional role of regulating some cellular metabolism during the evolutionary process. Interestingly, deletion of AFT2 in C. albicans increased cell surface hydrophobicity, cell flocculation and the ability of adhesion to polystyrene surfaces. In addition, our results also revealed that C. albicans Aft2 played a dual role in regulating hypha-specific genes under solid and liquid hyphal inducing conditions. Deletion of AFT2 caused an impaired invasive growth in solid medium, but an increased filamentous aggregation and growth in liquid conditions. Moreover, iron deficiency and environmental cues induced nuclear import of Aft2, providing additional evidence for the roles of Aft2 in transcriptional regulation.
PMCID: PMC3633901  PMID: 23626810
16.  Activity in motor-sensory projections reveals distributed coding in somatosensation 
Nature  2012;489(7415):299-303.
Cortical feed-back projections to primary sensory areas terminate most heavily in layer (L) 11,2, where they make synapses with tuft dendrites of pyramidal neurons. L1 input is thought to provide ‘contextual’ information3, but the signals transmitted by L1 feedback remain uncharacterized. In the rodent somatosensory system, the spatially diffuse4 vibrissal motor cortex (vM1)→ vibrissal somatosensory cortex (barrel cortex, vS1) feedback projection may allow whisker touch to be interpreted in the context of whisker position to compute object location5,6. When mice palpate objects with their whiskers to localize object features7,8, whisker touch excites vibrissal somatosensory cortex (barrel cortex, vS1)9 and later vibrissal motor cortex (vM1) in a somatotopic manner10,11,12,13. Here we used axonal calcium imaging to track activity in vM1→ vS1 afferents in L1 of barrel cortex, while mice performed whisker-dependent object localization. Spatially intermingled individual axons represented whisker movements, touch, and other behavioral features. In a subpopulation of axons, activity depended on object location and persisted for seconds after touch. Neurons in the barrel cortex thus have information to integrate movements and touches of multiple whiskers over time, key components of object identification and navigation by active touch.
PMCID: PMC3443316  PMID: 22922646
17.  NDRG2 Is a Novel p53-Associated Regulator of Apoptosis in C6-Originated Astrocytes Exposed to Oxygen-Glucose Deprivation 
PLoS ONE  2013;8(2):e57130.
N-myc downstream-regulated gene 2 (NDRG2) has been documented to be a pro-differentiative and anti-proliferative gene in cancer research. Our previous study found a significant NDRG2 up-regulation in reactive astrocytes of penumbra after transient focal cerebral ischemia, which was parallel to the enhancement of TUNEL-positive signals. However, it is still uncertain whether NDRG2 participates in cellular apoptosis induced by ischemia-reperfusion injury in brain. In this study, we investigated the role of NDRG2 in cellular apoptosis induced by oxygen-glucose deprivation (OGD) in IL-6-differentiated C6 glioma cells. The results showed that NDRG2 was up-regulated and translocated from the cytoplasm to the nucleus after OGD exposure. NDRG2 over-expression exhibited an anti-proliferative effect and increased the Bax/Bcl-2 ratio after OGD exposure, while NDRG2 silencing promoted the cellular proliferation and attenuated the up-regulation of Bax/Bcl-2 ratio. The pro-apoptotic effect of p53 was verified by the results in which p53 silencing greatly reduced the percentage of OGD-induced apoptotic cells. p53 silencing also reduced the OGD-induced NDRG2 up-regulation. However, over-expression of p53 did not further improve the NDRG2 up-regulation. In conclusion, NDRG2 is a p53-associated regulator of apoptosis in C6-originated astrocytes after OGD exposure. These findings bring insight to the roles of NDRG2 in ischemic-hypoxic injury and provide potential targets for future clinical therapies on stroke.
PMCID: PMC3579777  PMID: 23451161
18.  Facilitated Diffusion of Acetonitrile Revealed by Quantitative Breath Analysis Using Extractive Electrospray Ionization Mass Spectrometry 
Scientific Reports  2013;3:1205.
By using silver cations (Ag+) as the ionic reagent in reactive extractive electrospray ionization mass spectrometry (EESI-MS), the concentrations of acetonitrile in exhaled breath samples from the volunteers including active smokers, passive smokers, and non-smokers were quantitatively measured in vivo, without any sample pretreatment. A limit of detection (LOD) and relative standard deviation (RSD) were 0.16 ng/L and 3.5% (n = 8), respectively, for the acetonitrile signals in MS/MS experiments. Interestingly, the concentrations of acetonitrile in human breath continuously increased for 1–4 hours after the smoker finished smoking and then slowly decreased to the background level in 7 days. The experimental data of a large number of (> 165) samples indicated that the inhaled acetonitrile is excreted most likely by facilitated diffusion, instead of simple diffusion reported previously for other volatile compounds.
PMCID: PMC3564039  PMID: 23386969
19.  Liposarcoma of the spermatic cord mimicking a left inguinal hernia: a case report and literature review 
Liposarcoma of the spermatic cord (LSC) is a rare condition characterized by a painless inguinal or scrotal mass. To our knowledge, only about 200 cases have been previously reported in the literature. These tumors are often mistaken for common scrotal swellings, such as hydroceles and hernias. We present a LSC case in which a definitive diagnosis was obtained upon histological examination. We also provide a literature review of other cases that have been reported.
PMCID: PMC3585812  PMID: 23351168
Liposarcoma; Spermatic cord; Inguinal hernia; Literature review
20.  Prone versus Modified Supine Position in Percutaneous Nephrolithotomy: a Prospective Randomized Study 
Objective: To perform a prospective randomized trial comparing the efficacy and safety of percutaneous nephrolithotomy (PCNL) in the prone and modified supine positions.
Methods: Between August 2010 and August 2011, 102 patients with renal calculi and 20 patients with ureteral calculi were randomized to undergo fluoroscopy and ultrasound-guided PCNL procedures in the prone or modified supine position. Baseline characteristics, puncture position, numbers of punctures, operation time, stone free rate, loss of blood, hospital stay and second phase PCNL were compared in the two groups.
Results: There were no significant differences in gender, age, body mass index, stone location, stone size and the presence of hydronephrosis between the two groups. The rate of second PCNL was significantly higher and the stone clearance rate was significantly lower in the modified supine than in the prone position group. Mean operation time was significantly lower in the prone than in the modified supine position group (78 min vs 88 min, P<0.05). There were no significant differences in rates of rib and calyx puncture, numbers of punctures, mean blood loss, and mean hospital stay between the two groups.
Conclusions: Both the prone and modified supine positions are effective and safe for PCNL. Operation time was longer in the modified supine group, and patients undergoing PCNL in the modified supine position more frequently required a second operation due to a lower stone clearance rate.
PMCID: PMC3775109  PMID: 24046526
percutaneous nephrolithotomy; prone position; modified supine position; prospective randomized trial
21.  Geometric Distortion Correction for Echo Planar Images Using Nonrigid Registration with Spatially Varying Scale 
Magnetic resonance imaging  2008;26(10):1388-1397.
One method used to correct geometric and intensity distortions in Echo Planar images is to register them to undistorted images via nonrigid deformations. However some areas in the Echo Planar images are more distorted than others, thus suggesting the use of deformations whose characteristics are adapted spatially. In this paper, we incorporate into our previously developed registration algorithm a spatially varying scale mechanism, which adapts the local scale properties of the transformation by means of a scale map. To compute the scale map, a technique is proposed that relies on an estimate of the expected deformation field. This estimate is generated using knowledge of the physical processes that induce distortions in EPI images. We evaluate the method of spatially varying scale on both simulated and real data. We find that, in comparison with our earlier method using fixed scale, our new method finds deformation fields that are smoother and finds them faster without sacrificing accuracy.
PMCID: PMC3511831  PMID: 18499382
Nonrigid registration; spatially varying scale; distortion correction; echo planar images; regularization
22.  NELF Is a Nuclear Protein Involved in Hypothalamic GnRH Neuronal Migration 
Nasal embryonic LHRH factor (NELF) has been hypothesized to participate in the migration of GnRH and olfactory neurons into the forebrain, a prerequisite for normal hypothalamic-pituitary-gonadal function in puberty and reproduction. However, the biological functions of NELF, which has no homology to any human protein, remain largely elusive. Although mRNA expression did not differ, NELF protein expression was greater in migratory than postmigratory GnRH neurons. Pituitary Nelf mRNA expression was also observed and increased three-fold after exogenous GnRH administration. Contrary to a previous report, NELF displayed predominant nuclear localization in GnRH neurons, confirmed by mutagenesis of a putative nuclear localization signal resulting in impaired nuclear expression. NELF knockdown impaired GnRH neuronal migration of NLT cells in vitro. These findings and the identification of two putative zinc fingers suggest that NELF could be a transcription factor. Collectively, our findings implicate NELF as a nuclear protein involved in the developmental function of the reproductive axis.
PMCID: PMC3437992  PMID: 20025934
NELF; Nasal embryonic LHRH factor; GnRH neuron migration; Kallmann syndrome; hypogonadotropic hypogonadism
23.  N-[(2S)-2-Chloro­propano­yl]glycine 
The title compound, C5H8ClNO3, was prepared by the nucleophilic substitution reaction of (2S)-2-chloro­propanoyl chloride with glycine. The acetate group forms a dihedral angle of 84.6 (1)° with the mean plane of the C—NH—C=O fragment. In the crystal, the molecules are linked by N—H⋯O and O—H⋯O hydrogen bonds, generating a three-dimensional network, which consolidates the crystal packing.
PMCID: PMC3435838  PMID: 22969684
24.  Diethyl 3,3′-(phenyl­methyl­ene)bis­(1H-indole-2-carboxyl­ate) 
In the title compound, C29H26N2O4, the benzene ring is twisted by 73.5 (5) and 84.9 (3)° with respect to the mean planes of the two indole ring systems; the mean planes of the indole ring systems are oriented at a dihedral angle of 82.0 (5)°. In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds into chains.
PMCID: PMC3435799  PMID: 22969645
25.  Hemicelluloses negatively affect lignocellulose crystallinity for high biomass digestibility under NaOH and H2SO4 pretreatments in Miscanthus 
Lignocellulose is the most abundant biomass on earth. However, biomass recalcitrance has become a major factor affecting biofuel production. Although cellulose crystallinity significantly influences biomass saccharification, little is known about the impact of three major wall polymers on cellulose crystallization. In this study, we selected six typical pairs of Miscanthus samples that presented different cell wall compositions, and then compared their cellulose crystallinity and biomass digestibility after various chemical pretreatments.
A Miscanthus sample with a high hemicelluloses level was determined to have a relatively low cellulose crystallinity index (CrI) and enhanced biomass digestibility at similar rates after pretreatments of NaOH and H2SO4 with three concentrations. By contrast, a Miscanthus sample with a high cellulose or lignin level showed increased CrI and low biomass saccharification, particularly after H2SO4 pretreatment. Correlation analysis revealed that the cellulose CrI negatively affected biomass digestion. Increased hemicelluloses level by 25% or decreased cellulose and lignin contents by 31% and 37% were also found to result in increased hexose yields by 1.3-times to 2.2-times released from enzymatic hydrolysis after NaOH or H2SO4 pretreatments. The findings indicated that hemicelluloses were the dominant and positive factor, whereas cellulose and lignin had synergistic and negative effects on biomass digestibility.
Using six pairs of Miscanthus samples with different cell wall compositions, hemicelluloses were revealed to be the dominant factor that positively determined biomass digestibility after pretreatments with NaOH or H2SO4 by negatively affecting cellulose crystallinity. The results suggested potential approaches to the genetic modifications of bioenergy crops.
PMCID: PMC3462114  PMID: 22883929

Results 1-25 (59)