Effects of New Psychoactive Substance Esketamine on Behaviors and Transcription of Genes in Dopamine and GABA Pathways in Zebrafish Larvae.

Esketamine (ESK) is the S-enantiomer of ketamine racemate (a new psychoactive substance) that can result in illusions, and alter hearing, vision, and proprioception in human and mouse. Up to now, the neurotoxicity caused by ESK at environmental level in fish is still unclear. This work studied the effects of ESK on behaviors and transcriptions of genes in dopamine and GABA pathways in zebrafish larvae at ranging from 12.4 ng L- 1 to 11141.1 ng L- 1 for 7 days post fertilization (dpf). The results showed that ESK at 12.4 ng L- 1 significantly reduced the touch response of the larvae at 48 hpf. ESK at 12.4 ng L- 1 also reduced the time and distance of larvae swimming at the outer zone during light period, which implied that ESK might potentially decrease the anxiety level of larvae. In addition, ESK increased the transcription of th, ddc, drd1a, drd3 and drd4a in dopamine pathway. Similarly, ESK raised the transcription of slc6a1b, slc6a13 and slc12a2 in GABA pathway. This study suggested that ESK could affect the heart rate and behaviors accompanying with transcriptional alterations of genes in DA and GABA pathways at early-staged zebrafish, which resulted in neurotoxicity in zebrafish larvae.

Chronic Paternal/Maternal Exposure to Environmental Concentrations of Imidacloprid and Thiamethoxam Causes Intergenerational Toxicity in Zebrafish Offspring.

Imidacloprid (IMI) and thiamethoxam (THM) are ubiquitous in aquatic ecosystems. Their negative effects on parental fish are investigated while intergenerational effects at environmentally relevant concentrations remain unclear. In this study, F0 zebrafish exposed to IMI and THM (0, 50, and 500 ng L-1) for 144 days post-fertilization (dpf) was allowed to spawn with two modes (internal mating and cross-mating), resulting in four types of F1 generations to investigate the intergenerational effects. IMI and THM affected F0 zebrafish fecundity, gonadal development, sex hormone and VTG levels, with accumulations found in F0 muscles and ovaries. In F1 generation, paternal or maternal exposure to IMI and THM also influenced sex hormones levels and elevated the heart rate and spontaneous movement rate. LncRNA-mRNA network analysis revealed that cell cycle and oocyte meiosis-related pathways in IMI groups and steroid biosynthesis related pathways in THM groups were significantly enriched in F1 offspring. Similar transcriptional alterations of dmrt1, insl3, cdc20, ccnb1, dnd1, ddx4, cox4i1l, and cox5b2 were observed in gonads of F0 and F1 generations. The findings indicated that prolonged paternal or maternal exposure to IMI and THM could severely cause intergenerational toxicity, resulting in developmental toxicity and endocrine-disrupting effects in zebrafish offspring.

The colonic metabolism differences of main alkaloids in normal and colitis mice treated with Coptis chinensis Franch. and Sophora flavescens Ait. herbal pair using liquid chromatography-high resolution mass spectrometry method combined with chemometrics.

Coptis chinensis Franch. and Sophora flavescens Ait. is a herbal pair frequently used in treating ulcerative colitis. However, the bio-disposition profile of the major components in the inflamed gut remains unclear, which is essential to understand the pharmacological material basis of this herb pair. Here we established an integral quantitative and chemometric method to deduce the colonic metabolism differences of this herbal pair in normal and colitis mice. With this LC-MS method, a total of 41 components have been found in the Coptis chinensis Franch. and Sophora flavescens Ait. extract, and 28 metabolites were found in the colon after oral administration. Alkaloid and its phase I metabolites were the main components in the colon of normal and colitis mice. The results of principal component analysis at 6 h after oral administration showed significant colonic metabolism differences between normal and colitis mice. Heamap results showed that colitis induced significant changes in the colonic bio-disposition of this herbal pair extract. In particular, in the context of colitis, the phase I metabolism of berberine, coptisine, jatrorrhizine, palmatine,and epiberberine has been inhibited. These results may provide a basis for understanding the pharmacological material basis of Coptis chinensis Franch. and Sophora flavescens Ait. in treating ulcerative colitis.

A Time-course Transcriptional Kinetics of Genes in Behavior, Cortisol Synthesis and Neurodevelopment in Zebrafish Larvae Exposed to Imidacloprid and Thiamethoxam.

Agricultural use of neonicotinoid insecticides, neuroactive nitroguanidine compounds, has been detected everywhere in the global, posing significant hazard to nontarget organisms. This work studied the developmental neurotoxicity of zebrafish larvae exposed to imidacloprid (IMI) and thiamethoxam (THM), ranging from 0.05 µg L- 1 to 50 µg L- 1 for 35 days. Transcriptions of genes belonging to the behavior, neurodevelopment and cortisol synthesis in zebrafish larvae were monitored. The qPCR data demonstrated that with exposure time increased, the transcription of behavior related genes was down-regulated in both IMI and THM groups, such as macf1, cdh6 and syt10. Additionally, IMI and THM significantly up-regulated the transcriptions of actha, and down-regulated il1rapl1b and pi4k2a at 35 dpf. Importantly, IMI markedly enhanced the transcripiton of gfap, shha, nkx2.2a and nestin in a time dependent manner. This work provided the foundation for understanding zebrafish larvae's neurotoxicity induced by IMI and THM.

The design, synthesis and cellular imaging of a tumor-anchored, potent and cell-permeable BRD4-targeted fluorescent ligands.

Bromodomain 4 (BRD4) proteins play an important role in histone post-translational modifications and facilitate several important physiological and pathological processes, including cancers. The inhibition of BRD4 by small molecule inhibitors shows promise as a therapeutic strategy for cancer treatment. However, their clinical applications were limited, which is largely hampered by off-target effects-induced toxicity. We herein report the design, synthesis, and cellular imaging of a set of tumor-anchored and BRD4-targeted fluorescent ligands by introducing selective and potent BRD4 inhibitor into different fluorophores via variable linkers. One of the fluorescent conjugates (compound 6) was demonstrated to be cell-permeable and low cytotoxic, preferentially accumulated in cancer cells, and display pronounced fluorescent signal. More importantly, 6 was identified to show specific BRD4 engagement in the cellular content. Collectively, this study provides a pathway for developing labeled BRD4 ligands and highlights that compound 6 may represent a valuable tool for explorative learning and target delivery study of BRD4.

Imidacloprid and thiamethoxam affect synaptic transmission in zebrafish.

Imidacloprid (IMI) and thiamethoxam (THM) are two commonly applied neonicotinoid insecticides. IMI and THM could cause negative impacts on non-target organisms like bees. However, the information about neurotoxicity of IMI and THM in fish is still scarce. Here we investigated the effects of IMI and THM on locomotor behavior, AChE activity, and transcription of genes related to synaptic transmission in zebrafish exposed to IMI and THM with concentrations of 50 ng L-1 to 50,000 ng L-1 at 14 day post fertilization (dpf), 21 dpf, 28 dpf and 35 dpf. Our results showed that IMI and THM significantly influenced the locomotor activity in larvae at 28 dpf and 35 dpf. THM elevated AChE activity at 28 dpf. The qPCR data revealed that IMI and THM affected the transcription of marker genes belonging to the synapse from 14 dpf to 35 dpf. Furthermore, IMI and THM mainly affected transcription of key genes in γ-aminobutyric acid, dopamine and serotonin pathways in larvae at 28 dpf and 35 dpf. These results demonstrated the neurotoxicity of IMI and THM in zebrafish. The findings from this study suggested that IMI and THM in the aquatic environment may pose potential risks to fish fitness and survival.

[Application of 3.0T Time-of-flight Magnetic Resonance Angiography with Sparse Undersampling and Iterative Reconstruction in the Diagnosis of Unruptured Intracranial Aneurysms].

OBJECTIVE: To evaluate the diagnostic value of 3.0T time-of-flight MR angiography with sparse undersampling and iterative reconstruction (TOFu-MRA) for unruptured intracranial aneurysms (UIAs) on the basis of using digital subtraction angiography (DSA) as the reference standard. METHODS: A total of 65 patients with suspected UIAs were prospectively enrolled and all patients underwent TOFu-MRA and DSA. Relying on DSA as the reference standard, the sensitivity (SEN), specificity (SPE), positive predictive value (PPV) and negative predictive value (NPV) of using TOFu-MRA in UIA diagnosis were calculated, and the inter-observer agreement between two doctors was determined. Comparison of maximum intensity projection (MIP) and volume rendering (VR) image datasets was made to evaluate the agreement between DSA results and TOFu-MRA in the measurement of UIA morphological parameters, including the neck width (D neck), height (H) , and width (D width) of UIAs. RESULTS: The study covered 55 UIAs from 46 patients. The SEN, SPE, PPV and NPV of the two doctors using TOFu-MRA in UIA diagnosis were as follows: (95.7%, 95.7%), (94.7%, 94.7%), (97.8%, 97.8%) and (90.0%, 90.0%), respectively for patient-based assessment; (96.4%, 94.5%), (94.7%, 94.7%), (98.1%, 98.1%) and (90.0%, 85.7%), respectively, for aneurysm-based assessment. There is a strong inter-observer agreement (Kappa=0.93 for patient-based assessment and 0.96 for aneurysm-based assessment) between the two doctors. Moreover, Bland-Altman analysis showed that more than 95% points fell within the limits of agreement (LoA), suggesting strong agreement between the two examination methods for the measurement of UIAs morphological parameters. CONCLUSION: TOFu-MRA showed good diagnostic efficacy for UIAs and the results were in good agreement with those of DSA, the reference standard, for assessing UIA morphological parameter. TOFu-MRA can be used as a first choice for noninvasive diagnostic evaluation of UIAs.

[Noise Reduction Effect of Deep-learning-based Image Reconstruction Algorithms in Thin-section Chest CT].

OBJECTIVE: To evaluate the noise reduction effect of deep learning-based reconstruction algorithms in thin-section chest CT images by analyzing images reconstructed with filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR), and deep learning image reconstruction (DLIR) algorithms. METHODS: The chest CT scan raw data of 47 patients were included in this study. Images of 0.625 mm were reconstructed using six reconstruction methods, including FBP, ASIR hybrid reconstruction (ASIR50%, ASIR70%), and deep learning low, medium and high modes (DL-L, DL-M, and DL-H). After the regions of interest were outlined in the aorta, skeletal muscle and lung tissue of each group of images, the CT values, SD values and signal-to-noise ratio (SNR) of the regions of interest were measured, and two radiologists evaluated the image quality. RESULTS: CT values, SD values and SNR of the images obtained by the six reconstruction methods showed statistically significant difference ( P<0.001). There were statistically significant differences in the image quality scores of the six reconstruction methods ( P<0.001). Images reconstruced with DL-H have the lowest noise and the highest overall quality score. CONCLUSION: The model based on deep learning can effectively reduce the noise of thin-section chest CT images and improve the image quality. Among the three deep-learning models, DL-H showed the best noise reduction effect.

[The Application Value of Artificial Intelligence-based Filtering and Interpolated Image Reconstruction Algorithm in Abdominal Magnetic Resonance Image Denoising].

OBJECTIVE: To compare the noise reduction performance of conventional filtering and artificial intelligence-based filtering and interpolation (AIFI) and to explore for optimal parameters of applying AIFI in the noise reduction of abdominal magnetic resonance imaging (MRI). METHODS: Sixty patients who underwent upper abdominal MRI examination in our hospital were retrospectively included. The raw data of T1-weighted image (T1WI), T2-weighted image (T2WI), and dualecho sequences were reconstructed with two image denoising techniques, conventional filtering and AIFI of different levels of intensity. The difference in objective image quality indicators, peak signal-to-noise ratio (pSNR) and image sharpness, of the different denoising techniques was compared. Two radiologists evaluated the image noise, contrast, sharpness, and overall image quality. Their scores were compared and the interobserver agreement was calculated. RESULTS: Compared with the original images, improvement of varying degrees were shown in the pSNR and the sharpness of the images of the three sequences, T1W1, T2W2, and dual echo sequence, after denoising filtering and AIFI were used (all P<0.05). In addition, compared with conventional filtering, the objective quality scores of the reconstructed images were improved when conventional filtering was combined with AIFI reconstruction methods in T1WI sequence, AIFI level≥3 was used in T2WI and echo1 sequence, and AIFI level≥4 was used in echo2 sequence (all P<0.05). The subjective scores given by the two radiologists for the image noise, contrast, sharpness, and overall image quality in each sequence of conventional filtering reconstruction, AIFI reconstruction (except for AIFI level=1), and two-method combination reconstruction were higher than those of the original images (all P<0.05). However, the image contrast scores were reduced for AIFI level=5. There was good interobserver agreement between the two radiologists (all r>0.75, P<0.05). After multidimensional comparison, the optimal parameters of using AIFI technique for noise reduction in abdominal MRI were conventional filtering+AIFI level=3 in the T1WI sequence and AIFI level=4 in the T2WI and dualecho sequences. CONCLUSION: AIFI is superior to filtering in imaging denoising at medium and high levels. It is a promising noise reduction technique. The optimal parameters of using AIFI for abdominal MRI are Filtering+AIFI level=3 in the T1WI sequence and AIFI level=4 in T2WI and dualecho sequences.

[Application of Deep Learning Reconstruction Algorithm in Low-Dose Thin-Slice Liver CT of Healthy Volunteers].

OBJECTIVE: To explore the clinical feasibility of applying deep learning (DL) reconstruction algorithm in low-dose thin-slice liver CT examination of healthy volunteers by comparing the reconstruction algorithm based on DL, filtered back projection (FBP) reconstruction algorithm and iterative reconstruction (IR) algorithm. METHODS: A standard water phantom with a diameter of 180 mm was scanned, using the 160 slice multi-detector CT scanning of United Imaging Healthcare, to compare the noise power spectrums of DL, FBP and IR algorithms. 100 healthy volunteers were prospectively enrolled, with 50 assigned to the normal dose group (ND) and 50 to the low dose group (LD). IR algorithm was used in the ND group to reconstruct images, while DL, FBP and IR algorithms were used in the LD group to reconstruct images. One-way analysis of variance was used to compare the liver CT values, the liver noise, liver signal-to-noise ratio (SNR), contrast noise ratio (CNR) and figure of merit (FOM) of the images of ND-IR, LD-FBP, LD-IR and LD-DL. The Kruskal-Wallis test was used to analyse subjective scores of anatomical structures. RESULTS: The DL algorithm had the lowest average peak value of noise power spectrum, and its shape was similar to that of medium-level IR algorithm. Liver CT values of ND-IR, LD-FBP, LD-IR and LD-DL did not show statistically significant difference. The noise of LD-DL was lower than that of LD-FBP, LD-IR and ND-IR ( P<0.05), and the SNR, CNR and FOM of LD-DL were higher than those of LD-FBP, LD-IR and ND-IR ( P<0.05). The subjective scores of anatomical structures of LD-DL did not show significant difference compared to those of ND-IR ( P >0.05), and were higher than those of LD-FBP and LD-IR. The radiation dose of the LD group was reduced by about 50.2% compared with that of the ND group. CONCLUSION: The DL algorithm with noise shape similar to the medium iterative grade IR commonly used in clinical practice showed higher noise reduction ability than IR did. Compared with FBP, the DL algorithm had smoother noise shape, but much better noise reduction ability. The application of DL algorithm in low-dose thin-slice liver CT of healthy volunteers can help achieve the standard image quality of liver CT.

Bmi-1 determines the stemness of renal stem or progenitor cells.

Renal stem or progenitor cells (RSCs), labeled with CD24 and CD133, play an important role during the repair of renal injury. Bmi-1 is a critical factor in regulating stemness of adult stem cells or progenitor cells. To investigate whether Bmi-1 determines the stemness of RSCs by inhibiting p16 and p53, and/or maintaining redox balance, RSCs were isolated, cultured and analyzed for stemness characterizations. In RSCs from Bmi-1-deficient (Bmi-1-/-) mice and wild type (WT) littermates, self-renewal, stemness, and expressions of molecules for regulating redox balance and cell cycle progression were compared. Self-renewal of RSCs from Bmi-1 and p16 double-knockout (Bmi-1-/-p16-/-), Bmi-1 and p53 double-knockout (Bmi-1-/-p53-/-) and N-acetylcysteine (NAC)-treated Bmi-1-/- mice were further analyzed for amelioration. Human renal proximal tubular epithelial cells (HK2) were also used for signaling analysis. Our results showed that third-passage RSCs from WT mice had good stemness; Bmi-1 deficiency led to the decreased stemness, and the increased apoptosis for RSCs; NAC treatment or p16/p53 deletion ameliorated the decreased self-renewal of RSCs in Bmi-1 deficiency mice by maintaining redox balance or inhibiting cell cycle arrest respectively; Oxidative stress (OS) could negatively feedback regulate the mRNA expressions of Bmi-1, p16 and p53. In conclusion, Bmi-1 determined the stemness of RSCs through maintaining redox balance and preventing cell cycle arrest. Thus, Bmi-1 signaling molecules would be novel therapeutic targets for maintaining RSCs and hampering the progression of kidney diseases to prevent renal failure.

Aberrant expressed long non-coding RNAs in laryngeal squamous-cell carcinoma.

PURPOSE: Laryngeal squamous-cell carcinoma (LSCC) is the second most common malignant tumor of head and neck squamous cell carcinoma. The study was aimed to identify key long non-coding RNAs (lncRNAs) biomarkers for LSCC. METHODS: Differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs) between LSCC and adjacent tissues were obtained based on The Cancer Genome Atlas. DElncRNA-DEmRNAs co-expression and DElncRNA-nearby-target DEmRNA interaction networks were constructed. Receiver operating characteristic and survival analysis were performed. A published dataset were as used to validate the result of bioinformatics analysis. RESULTS: We obtained 1103 DEmRNAs and 306 DElncRNAs between LSCC and adjacent tissues. A total of 338 DElncRNA-DEmRNA co-expression pairs and 229 DElncRNA-nearby-target DEmRNA pairs were obtained. Ten DElncRNAs and six DEmRNAs has great diagnostic value for LSCC. HOXB9 has potential prognostic value for LSCC. The results of GSE84957 validation were generally consistent with our results. CONCLUSION: Our study provided clues for understanding the mechanism and developing potential biomarkers for LSCC.

Comprehensive analysis of gene expression and DNA methylation for human nasopharyngeal carcinoma.

PURPOSE: Nasopharyngeal carcinoma (NPC) is one of the most malignant head and neck carcinomas with unique epidemiological features. In this study, we aimed to identify the novel NPC-related genes and biological pathways, shedding light on the potential molecular mechanisms of NPC. METHODS: Based on Gene Expression Omnibus (GEO) database, an integrated analysis of microarrays studies was performed to identify differentially expressed genes (DEGs) and differentially methylated genes (DMGs) in NPC compared to normal control. The genes which were both differentially expressed and differentially methylated were identified. Functional annotation and protein-protein interaction (PPI) network construction were used to uncover biological functions of DEGs. RESULTS: Two DNA methylation and five gene expression datasets were incorporated. A total of 1074 genes were up-regulated and 939 genes were down-regulated in NPC were identified. A total of 719 differential methylation CpG sites (DMCs) including 1 hypermethylated sites and 718 hypomethylated sites were identified. Among which, 11 genes were both DEGs and DMGs in NPC. Pathways in cancer, p53 signaling pathway and Epstein-Barr virus infection were three pathways significantly enriched pathways in DEmRNAs of NPC. The PPI network of top 50 DEGs were consisted of 191 nodes and 191 edges. CONCLUSIONS: Our study was helpful to elucidate the underlying mechanism of NPC and provide clues for therapeutic methods.

[Automated Estimation of Stenosis Severity in Coronary Computed Tomography Angiography].

OBJECTIVE: To determine the value of automated detection in computed tomography angiography (CTA) for cases with greater than 70% coronary stenosis. METHODS: Fifty-seven patients who had both coronary CTA and digital subtraction angiography (DSA) were retrospectively recruited in this study. The patients were categorized into two groups using a cutoff value of 70% stenosis in DSA. The AW4.6 software was used to estimate the diameter and square values from the data obtained from CTA. The sensitivity (SE), specificity (SPE), positive predictive value (PPV) and negative predictive value (NPV) of the automated CTA estimations were calculated. RESULTS: A total of 178 vessels from the 57 patients were analyzed. The automated CTA estimations had moderate to high levels of agreements (Kappa value: 0.716-0.804, P < 0.001) with the DSA diagnoses, compared with low to moderate levels of agreements (Kappa value: 0.385-0.533, P < 0.001) in manual interpretations. The square estimations generated high SE (100%) and NPV (100%) for patient diagnoses (P < 0.016 7 vs. manual interpretations). The diameter estimations generated high SPE (90.48%) and PPV (94.12%) for patient diagnoses (P < 0.016 7, vs. manual interpretations). Similarly, high SE (96.92%) and NPV (97.89%) were found for square estimations in vessel diagnoses, while high SPE (94.69%) and PPV (90.16%) were found for diameter estimations in vessel diagnoses. CONCLUSIONS: Both automated diameter and square algorithms have high accuracy for diagnosing patients with greater than 70% coronary artery stenosis. The AW4.6 can improve the detection of severe stenosis that needs stent interventions.

[The Application Value of One-stop CT Myocardial Perfusion Imaging in the Evaluation of Patients with Severe Coronary Artery Stenosis].

ObstractPurpose "One-stop" CT myocardial perfusion imaging (CT-MPI) was compared with cardiac magnetic resonance(CMR) to investigate its application value in evaluating patients with severe coronary artery stenosis.MethodsFifty patients with coronary artery stenosis≥90% of at least one major coronary arteries comfirmed by coronary angiography (CAG) in the department of cardiology in our hospital, who referred for coronary artery stent implantation were prospectively enrolled. All the patients underwent "One-stop" CT-MPI within a week before surgery, among which 22 patients underwent CMR examination simultaneously. The postprocessing software Ziostation2 was used to obatin and compare the perfusion parameters of patients with normal and perfusion defect myocardium, including blood flow (BF), blood volume (BV), peak time (TTP), and mean transit time (MTT). Pearson correlation analysis was used to compare the correlation of relative perfusion parameters (defect/normal myocardium) between CT and CMR. Bland-Altman analysis was used to analyze the consistency between CT and CMR in left ventricular (LV) function parameters measurements.ResultsCompared with normal myocardium, BV and BF of perfusion defect myocardium were significantly decreased, while MTT and TTP were significantly prolonged (all P < 0.05). The rBV, rBF, rMTT and rTTP were medium to high positive correlated between CT and CMR (r=0.685, 0.641, 0.871, 0.733, respectively, all P < 0.05). Bland-Altman analysis showed that 95% (21/22) points were within the 95% limits of agreement (LoA), suggesting the LV function parameters measurements between two methods were highly consistent.Conclusion"One-stop" CT-MPI can simultaneously obtain the information about coronary anatomy, myocardial perfusion and LV function. It is of great value in the evaluation of patients with severe coronary artery stenosis, with shorter scan time and less contraindications compared with CMR.

Novel Magnetic Microprobe with Benzoboroxole-Modified Flexible Multisite Arm for High-Efficiency cis-Diol Biomolecule Detection.

With regard to regulating a variety of biological events, including molecular recognition, signal transduction, cell adhesion, and immune response, cis-diol biomolecules, such as saccharides and glycoproteins, play vital roles. However, saccharides and glycoproteins in living systems usually exist in very low abundance, along with abundant interfering components. High-efficiency detection of saccharides and glycoproteins is a challenging yet highly impactful area of research. Herein, we reported a novel magnetic microprobe with a benzoboroxole-modified flexible multisite arm (PEG 2000-grafted PAMAM dendrimers; the microprobe was denoted as BFMA-MNP) for high-efficiency saccharides detection. The extraction capacity was significantly improved by ∼2 orders of magnitude, because of the integration of the enhanced hydrophilicity and multivalency effects in benzoboroxoles and the enhanced accessibility of the binding sites within the PEG 2000-grafted PAMAM dendrimers. As a result, the proposed approach possessed several advantages, compared with previous boronic acid-based methods, including ultrahigh sensitivity (limit of detection was <1 ng/mL), wide linear range (ranged from 0.5 µM to 2000 µM), and applicable in physiological pH condition. Furthermore, we established a general BFMA-MNP/glycoproteins/AuNPs sandwich assay to realize the visual glycoprotein qualitative screening for the first time. The unique sandwich assay possessed the dual nature of the magnetic separation by BFMA-MNPs and specific coloration by citrate-coated AuNPs. This visual sandwich assay enabled fast differentiation of the existence of glycoproteins in complicated samples without any advanced instruments. We believe the proposed BFMA-MNP microprobe herein will advance the ideas to detect and identify trace saccharides and glycoproteins in important fields such as glycomics and glycoproteomics.

[Application of Low Concentration Contrast Agent Combined Double Low Dose in CT Pulmonary Angiography for Pulmonary Embolism].

OBJECTIVE: To investigate the feasibility of low concentration contrast agent combined double low dose in CT pulmonary angiography. METHODS: 60 patients with clinically suspected pulmonary embolism examed by CT pulmonary angiography (CTPA) were divided into two groups (experimental group: n=30,80 kV, 15 mL,320 mg I/mL;control group: n=30,120 kV,50 mL,370 mg I/mL). The average CT value of main right and left pulmonary arteries,lobar arteries was calculated. Imaging post processing techniques included curved plannar reconstruction (CPR),volume rendering (VR) and maximal intensity projection (MIP). The artifact of the remaining contract in the superior vena cava and overall quality of the image were observed and analyzed by two senior doctors who were double blinded. RESULTS: All patients in two groups completed CTPA successfully. The image qualities of two groupssatisfy clinical diagnostic requirements and no difference of the image qualities was observed between two groups (P>0.05). The evaluation of venous pollution in experimental group was better than that of control group (P<0.01).No difference of CT values were observed between two groups [experimental group (423.2±89.4) HU,control group (465.7±85.6) HU](P>0.05). The SNR and CNR in experimental group were lower than those in control group (P<0.01 both).The CT dose index volume (CTDIvol),dose-length product (DLP) and size-specific dose estimates (SSDE) in experimental group were significantly lower than those incontrol group (P<0.01 all). CONCLUSION: The low concentration contrast agent combined double low dose in CT pulmonary angiography satisfies clinical diagnostic requirements. It has good clinical value for it could reduce venous pollution,iodine contrast agent and radiation exposure.

[Comparison of MR Perfusion Weighted Imaging and CT Perfusion Imaging in Assessing Hemodynamics of Patients with Moyamoya Disease].

OBJECTIVE: To determine consistencies between MR perfusion weighted imaging (PW-MRI) and CT perfusion imaging (CTP) in assessing hemodynamics of patients with moyamoya disease (MMD). METHODS: Images of PWI and CTP scan [including the map of cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), and mean transmit time (MTT)] of 24 MMD patients diagnosed by digital subtraction angiography(DSA) or time of flight-MR angiography (TOF-MRA) were obtained in the week before vascular reconstruction operations. Relative perfusion parameters (rCBF, rCBV, rMTT, rTTP) at the operative side within the middle cerebral artery territory and cerebellar hemisphere were compared with those of 17 patients without hypoperfusion and cerebrovascular disease using independent sample t test. Paired t test and Pearson correlation analyses were performed between the results of PWI-MRI and CTP. RESULTS: Different parameters were found in the MMD patients compared with the controls (P<0.05). The parameter results of PWI-MRI differed from those of CTP, but they were strongly correlated. CONCLUSION: Both PWI-MRI and CTP can detect the area and degree of hypoperfusion of MMD patients.

The Long Intron 1 of Growth Hormone Gene from Reeves' Turtle (Chinemys reevesii) Correlates with Negatively Regulated GH Expression in Four Cell Lines.

Turtles grow slowly and have a long lifespan. Ultrastructural studies of the pituitary gland in Reeves' turtle (Chinemys reevesii) have revealed that the species possesses a higher nucleoplasmic ratio and fewer secretory granules in growth hormone (GH) cells than other animal species in summer and winter. C. reevesii GH gene was cloned and species-specific similarities and differences were investigated. The full GH gene sequence in C. reevesii contains 8517 base pairs (bp), comprising five exons and four introns. Intron 1 was found to be much longer in C. reevesii than in other species. The coding sequence (CDS) of the turtle's GH gene, with and without the inclusion of intron 1, was transfected into four cell lines, including DF-1 chicken embryo fibroblasts, Chinese hamster ovary (CHO) cells, human embryonic kidney 293FT cells, and GH4C1 rat pituitary cells; the turtle growth hormone (tGH) gene mRNA and protein expression levels decreased significantly in the intron-containing CDS in these cell lines, compared with that of the corresponding intronless CDS. Thus, the long intron 1 of GH gene in Reeves' turtle might correlate with downregulated gene expression.

[Radiation Dose of Body Surface at Sensitive Organs and Its Protective Precaution in Head CT Scanning:Initial Experience.]

OBJECTIVES: To investigate the radiation dose of body surface at sensitive organs using different protective precaution in head CT scanning. METHODS: The standard phantom received head routine sequence scanning with dual-source computed tomography.The phantoms were scanned with three different protective precaution:group A (without protective clothing),group B (wearing lead collar and cover lead clothes),group C (wearing lead collar and clothes without cuffs).The thermoluminescence dosimeters (TLD) was placed on the body surface corresponding to sensitive organs to measure radiation dose. RESULTS: The volume of CT dose index (CTDIvol) and dose length product (DLP) in group A,B and C were same,44.06 mGy and 634 mGy×cm,respectively.There was no statistic significant difference between group A,B and C of radiation dose in non-protective region (P=0.712).The radiation dose in the neck region under the cover of lead collar in group A,B and C were (2.57 ± 0.65) mGy,(2.30 ± 1.10) mGy and (2.48 ± 0.90) mGy,respectively,without statistic significant difference between groups (P=0.816).However,the radiation dose in abdominal region of group A was (0.66±0.37) mGy,which was significantly higher than that of group B [(0.18 ± 0.18) mGy] and group C [(0.18±0.16) mGy],The radiation dose in dorsal region of group A was (0.55±0.43) mGy,which was significantly higher than that of group B [(0.28±0.22) mGy],while that of group C [(0.14±0.12) mGy] was significantly lower than group B. CONCLUSIONS: Compared to traditional lead coverage,lead collar and cloth can decrease the radiation dose of body surface and sensitive organs in head scan with dual source CT.