The origin of different bending stiffness between double-stranded RNA and DNA revealed by magnetic tweezers and simulations.

The subtle differences in the chemical structures of double-stranded (ds) RNA and DNA lead to significant variations in their biological roles and medical implications, largely due to their distinct biophysical properties, such as bending stiffness. Although it is well known that A-form dsRNA is stiffer than B-form dsDNA under physiological salt conditions, the underlying cause of this difference remains unclear. In this study, we employ high-precision magnetic-tweezer experiments along with molecular dynamics simulations and reveal that the relative bending stiffness between dsRNA and dsDNA is primarily determined by the structure- and salt-concentration-dependent ion distribution around their helical structures. At near-physiological salt conditions, dsRNA shows a sparser ion distribution surrounding its phosphate groups compared to dsDNA, causing its greater stiffness. However, at very high monovalent salt concentrations, phosphate groups in both dsRNA and dsDNA become fully neutralized by excess ions, resulting in a similar intrinsic bending persistence length of approximately 39 nm. This similarity in intrinsic bending stiffness of dsRNA and dsDNA is coupled to the analogous fluctuations in their total groove widths and further coupled to the similar fluctuation of base-pair inclination, despite their distinct A-form and B-form helical structures.

Universality in RNA and DNA deformations induced by salt, temperature change, stretching force, and protein binding.

Nucleic acid deformations play important roles in many biological processes. The physical understanding of nucleic acid deformation by environmental stimuli is limited due to the challenge in the precise measurement of RNA and DNA deformations and the complexity of interactions in RNA and DNA. Magnetic tweezers experiments provide an excellent opportunity to precisely measure DNA and RNA twist changes induced by environmental stimuli. In this work, we applied magnetic tweezers to measure double-stranded RNA twist changes induced by salt and temperature changes. We observed RNA unwinds when lowering salt concentration, or increasing temperature. Our molecular dynamics simulations revealed the mechanism: lowering salt concentration or increasing temperature enlarges RNA major groove width, which causes twist decrease through twist-groove coupling. Combining these results with previous results, we found some universality in RNA and DNA deformations induced by three different stimuli: salt change, temperature, and stretching force. For RNA, these stimuli first modify the major groove width, which is transduced into twist change through twist-groove coupling. For DNA, these stimuli first modify diameter, which is transduced into twist change through twist-diameter coupling. Twist-groove coupling and twist-diameter coupling appear to be utilized by protein binding to reduce DNA and RNA deformation energy cost upon protein binding.

A mutation-sensitive, multiplexed and amplification-free detection of nucleic acids by stretching single-molecule tandem hairpin probes.

The detection of nucleic acid sequences in parallel with the discrimination of single nucleotide variations (SNVs) is critical for research and clinical applications. A few limitations make the detection technically challenging, such as too small variation in probe-hybridization energy caused by SNVs, the non-specific amplification of false nucleic acid fragments and the few options of dyes limited by spectral overlaps. To circumvent these limitations, we developed a single-molecule nucleic acid detection assay without amplification or fluorescence termed THREF (hybridization-induced tandem DNA hairpin refolding failure) based on multiplexed magnetic tweezers. THREF can detect DNA and RNA sequences at femtomolar concentrations within 30 min, monitor multiple probes in parallel, quantify the expression level of miR-122 in patient tissues, discriminate SNVs including the hard-to-detect G-U or T-G wobble mutations and reuse the probes to save the cost. In our demonstrative detections using mock clinic samples, we profiled the let-7 family microRNAs in serum and genotyped SARS-CoV-2 strains in saliva. Overall, the THREF assay can discriminate SNVs with the advantages of high sensitivity, ultra-specificity, multiplexing, reusability, sample hands-free and robustness.

5-Methyl-cytosine stabilizes DNA but hinders DNA hybridization revealed by magnetic tweezers and simulations.

5-Methyl-cytosine (5mC) is one of the most important DNA modifications and plays versatile biological roles. It is well known that 5mC stabilizes DNA duplexes. However, it remains unclear how 5mC affects the kinetics of DNA melting and hybridization. Here, we studied the kinetics of unzipping and rezipping using a 502-bp DNA hairpin by single-molecule magnetic tweezers. Under constant loading rates, 5mC increases the unzipping force but counterintuitively decreases the rezipping force at various salt and temperature conditions. Under constant forces, the non-methylated DNA hops between metastable states during unzipping and rezipping, which implies low energy barriers. Surprisingly, the 5mC DNA can't rezip after fully unzipping unless much lower forces are applied, where it rezips stochastically in a one-step manner, which implies 5mC kinetically hinders DNA hybridization and high energy barriers in DNA hybridization. All-atom molecular dynamics simulations reveal that the 5mC kinetically hinders DNA hybridization due to steric effects rather than electrostatic effects caused by the additional methyl groups of cytosines. Considering the possible high speed of DNA unzipping and zipping during replication and transcription, our findings provide new insights into the biological roles of 5mC.

Genome-wide association analysis for grain moisture content and dehydration rate on maize hybrids.

For mechanized maize production, a low grain water content (GWC) at harvest is necessary. However, as a complex quantitative trait, understand the genetic mechanism of GWC remains a large gap, especially in hybrids. In this study, a hybrid population through two environments including 442 F1 was used for genome-wide association analysis of GWC and the grain dehydration rate (GDR), using the area under the dry down curve (AUDDC) as the index. Then, we identified 19 and 17 associated SNPs for GWC and AUDDC, including 10 co-localized SNPs, along with 64 and 77 pairs of epistatic SNPs for GWC and AUDDC, respectively. These loci could explain 11.39-68.2% of the total phenotypic variation for GWC and 41.07-67.02% for AUDDC at different stages, whose major effect was the additive and epistatic effect. By exploring the candidate genes around the significant sites, a total of 398 and 457 possible protein-coding genes were screened, including autophagy pathway and auxin regulation-related genes, and five inbred lines with the potential to reduce GWC in the combined F1 hybrid were identified. Our research not only provides a certain reference for the genetic mechanism analysis of GWC in hybrids but also provides an added reference for breeding low-GWC materials. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01349-x.

Enterolactone and trabectedin suppress epithelial ovarian cancer synergistically via upregulating THBS1.

Epithelial ovarian cancer (EOC) is the most common and fatal subtype of ovarian malignancies, with no effective therapeutics available. Our previous studies have demonstrated extraordinary suppressive efficacy of enterolactone (ENL) on EOC. A chemotherapeutic agent, trabectedin (Trabe), is shown to be effective on ovarian cancer, especially when combined with other therapeutics, such as pegylated liposomal doxorubicin or oxaliplatin. Thrombospondin 1 (THBS1), a kind of matrix glycoprotein, plays important roles against cancer development through inhibiting angiogenesis but whether it is involved in the suppression of EOC by ENL or Trabe remains unknown. To test combined suppressive effects of ENL and Trabe on EOC and possible involvement of THBS1 in the anticancer activities of ENL and Trabe. The EOC cell line ES-2 was transfected with overexpressed THBS1 by lentivirus vector. We employed tube formation assay to evaluate the anti-angiogenesis activity of ENL and of its combined use with Trabe after THBS1 overexpression and established drug intervention and xenograft nude mouse cancer models to assess the in vivo effects of the hypothesized synergistic suppression between the agents and the involvement of THBS1. Mouse fecal samples were collected for 16S rDNA sequencing and microbiota analysis. We detected strong inhibitory activities of ENL and Trabe against the proliferation and migration of cancer cells and observed synergistic effects between ENL and Trabe in suppressing EOC. ENL and Trabe, given either separately or in combination, could suppress the tube formation capability of human microvascular endothelial cells, and this inhibitory effect became even stronger with THBS1 overexpression. In the ENL plus Trabe combination group, the expression of tissue inhibitor of metalloproteinases 3 and cluster of differentiation 36 was both upregulated, whereas matrix metalloproteinase 9, vascular endothelial growth factor, and cluster of differentiation 47 were all decreased. With the overexpression of THBS1, the results became even more pronounced. In animal experiments, combined use of ENL and Trabe showed superior inhibitory effects to either single agent and significantly suppressed tumor growth, and the overexpression of THBS1 further enhanced the anti-cancer activities of the drug combination group. ENL and Trabe synergistically suppress EOC and THBS1 could remarkably facilitate the synergistic anticancer effects of ENL and Trabe.

Relationship of Microvascular Obstruction with Global and Regional Myocardial Function Determined by Cardiac Magnetic Resonance after ST-Segment Elevation Myocardial Infarction.

Objective To investigate the impact of microvascular obstruction (MVO) on the global and regional myocardial function by cardiac magnetic resonance feature-tracking (CMR-FT) in ST-segment-elevation myocardial infarction (STEMI) patients after percutaneous coronary intervention.Methods Consecutive acute STEMI patients who underwent cardiac magnetic resonance imaging 1 - 7 days after successful reperfusion by percutaneous coronary intervention treatment were included in this retrospective study. Based on the presence or absence of MVO on late gadolinium enhancement images, patients were divided into groups with MVO and without MVO. The infarct zone, adjacent zone, and remote zone were determined based on a myocardial 16-segment model. The radial strain (RS), circumferential strain (CS), and longitudinal strain (LS) of the global left ventricle (LV) and the infarct, adjacent, and remote zones were measured by CMR-FT from cine images and compared between patients with and without MVO using independent-samples t-test. Logistic regression analysis was used to assess the association of MVO with the impaired LV function.Results A total of 157 STEMI patients (mean age 56.66 ± 11.38 years) were enrolled. MVO was detected in 37.58% (59/157) of STEMI patients, and the mean size of MVO was 3.00 ±3.76 mL. Compared with patients without MVO (n =98 ), the MVO group had significantly reduced LV global RS (t= -4.30, P < 0.001), global CS (t= 4.99, P < 0.001), and global LS ( t= 3.51, P = 0.001). The RS and CS of the infarct zone in patients with MVO were significantly reduced (t= -3.38, P = 0.001; t= 2.64, P = 0.01; respectively) and the infarct size was significantly larger (t= 8.37, P < 0.001) than that of patients without MVO. The presence of LV MVO [OR= 4.10, 95%CI: 2.05 - 8.19, P<0.001) and its size [OR=1.38, 95%CI: 1.10-1.72, P=0.01], along with the heart rate and LV infarct size were significantly associated with impaired LV global CS in univariable Logistic regression analysis, while only heart rate (OR=1.08, 95%CI: 1.03 - 1.13, P=0.001) and LV infarct size (OR=1.10, 95%CI: 1.03 - 1.16, P=0.003) were independent influencing factors for the impaired LV global CS in multivariable Logistic regression analysis.Conclusion The infarct size was larger in STEMI patients with MVO, and MVO deteriorates the global and regional LV myocardial function.

[To evaluate the efficacy of Yishen Tongluo decoction combined with low-dose tadalafil in the treatment of diabetic erectile dysfunction with kidney deficiency and blood stasis syndrome].

OBJECTIVE: To observe the clinical efficacy of the combined treatment of Yishen Tongluo formula and low-dose tadalafil in diabetic erectile dysfunction. METHODS: A total of 80 patients with diabetic erectile dysfunction were randomly divided into two groups. The control group given tadalafil treatment, observation group in the control group given Yishen Tongluo Formula on the basis of treatment. The treatment period was 8 weeks. Erectile function were observed before and after treatment in the two groups patients-5 international questionnaire (IIEF - 5) score, erection quality scale (EQS) score, erectile hardness (EHS) score, TCM syndrome integral, content of serum homocysteine (HCY), endothelial function index ï¼»serum levels of prostaglandin I2 (PGI2)ï¼½ and endothelin (ET) content, a The changes of nitrogen oxide (NO), glucose and lipid metabolism indexes ï¼»triglyceride (TC), total cholesterol (TG)ï¼½ and oxidative stress related factors ï¼»total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px)ï¼½ were evaluated, and the clinical efficacy of the two groups was evaluated. RESULTS: In terms of overall efficacy rate, the observation group (79.4%) outperformed that of the control (48.7%, P< 0.01).After treatment, the IIEF-5 score, EQS score, EHS score, and serum levels of PGI2, NO, T-AOC and GSH-Px were higher than those before treatment in the two groups (P< 0.05). The TCM syndrome score and serum HCY, ET-1, TC and TG were lower than those before treatment (P< 0.05), and the comparison group's consequence was comparatively worse than the group under observation (P< 0.01). CONCLUSIONS: Yishen Tongluo Formula can dramatically enhance the erectile dysfunction andimprovement of glucose-lipid metabolism when adopted in together with low-dose tadalafil.

[Dumai moxibustion combined with low-dose tadalafil for erectile dysfunction: Evaluation of therapeutic effect].

OBJECTIVE: To investigate the clinical effect of dumai (governor meridian) moxibustion combined with low-dose tadalafil in the treatment of ED with decline of vital gate fire. METHODS: We enrolled in this study 130 ED patients with decline of vital gate fire who met the inclusion criteria and equally randomized them into a control and an experimental group, the former treated with low-dose tadalafil tablets at 5 mg once a day while the latter by dumai moxibustion once a week in addition, all for 4 weeks. Of the total number of subjects, 62 in the control group and 63 in the experimental group completed the experiment. We recorded the scores on IIEF-5, Erection Quality Scale (EQS), Erection Hardness Scale (EHS), TCM symptoms and Treatment Satisfaction Scale (TSS) as well as the penile hemodynamic parameters peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index (RI) before and after treatment and compared them between the two groups. RESULTS: The total response rate was significantly higher in the experimental group than in the control (87.30% vs 66.13%, P < 0.05). IIEF-5, EQS, EHS and TSS scores, PSV and RI were markedly increased while TCM symptoms and EDV remarkably decreased in both groups after treatment (P < 0.05), even more significantly in the experimental than in the control group (P < 0.05). CONCLUSION: Dumai moxibustion combined with low-dose tadalafil can improve erectile function, increase penile blood flow velocity and alleviate clinical symptoms in ED patients with decline of vital gate fire, with definite clinical effect and safety.

Multivalent Cations Reverse the Twist-Stretch Coupling of RNA.

When stretched, both DNA and RNA duplexes change their twist angles through twist-stretch coupling. The coupling is negative for DNA but positive for RNA, which is not yet completely understood. Here, our magnetic tweezers experiments show that the coupling of RNA reverses from positive to negative by multivalent cations. Combining with the previously reported tension-induced negative-to-positive coupling reversal of DNA, we propose a unified mechanism of the couplings of both RNA and DNA based on molecular dynamics simulations. Two deformation pathways are competing when stretched: shrinking the radius causes positive couplings but widening the major groove causes negative couplings. For RNA whose major groove is clamped by multivalent cations and canonical DNA, their radii shrink when stretched, thus exhibiting positive couplings. For elongated DNA whose radius already shrinks to the minimum and canonical RNA, their major grooves are widened when stretched, thus exhibiting negative couplings.

Genetic substructure analysis of three isolated populations in southwest China.

Southwest China is home to numerous ethnic minorities, as well as many geographically and genetically isolated groups. However, the genetic substructure of these ethnic groups, especially the paternal genetic structure between groups, has not been comprehensively analyzed. In this study, we used Y chromosome capture and Illumina sequencing technologies to investigate the paternal genetic structure of three isolated groups of male unrelated individuals, including Baima in Pingwu, Sichuan Province, Muya in Shimian, Sichuan Province, and Kongge in Jinghong, Yunnan Province. We calculated the frequencies of related haplogroups by the fixed-point compound amplification method and direct counting method, and used the Past3.0 software to perform principal component analysis to draw a population clustering tree. we observed that Kongge had 3 Y chromosome haplogroups, Baima had 4 Y chromosome haplogroups, and Muya had 5 Y chromosome haplogroups. The results showed that Kongge was most closely related to the Wa, and the Y chromosome types of the Baima and Muya were mainly concentrated in the D haplogroup and its lower reaches. It has the closest relationship with the Tibetans in Qamdo and Nyingchi. The study on the genetic structure of different ethnic groups has enriched the genetic relationship of isolated populations and provided a new perspective for understanding Chinese ethnic groups.

CircC3P1 attenuated pro-inflammatory cytokine production and cell apoptosis in acute lung injury induced by sepsis through modulating miR-21.

Acute lung injury (ALI) induced by sepsis is characterized by an inflammatory process related to the up-regulation of inflammatory cytokines and chemokines. In the present study, we explored the role of circC3P1 in sepsis-induced ALI in vitro and in vivo. The caecal ligation and puncture (CLP)-induced sepsis model was established through CLP surgery. Forty adult male C57BL/6 mice were randomly assigned into sham, CLP, CLP + vector and CLP + circC3P1 (each n = 10). Primary murine pulmonary microvascular endothelial cells (MPVECs) were transfected with circC3P1 or empty vector 24 hours prior to LPS treatment via Lipofectamine 2000. The expressions of circC3P1, tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1ß were evaluated after 6-h LPS treatment. Cell apoptosis was evaluated via flow cytometry. The CLP group demonstrated pulmonary morphological abnormalities, increased concentrations of TNF-α, IL-6 and IL-1ß in the lung tissue, compared with the sham group. MPVECs treated with LPS significantly elevated TNF-α, IL-6 and IL-1ß levels and increased cell apoptosis than that in the control group. The circC3P1 overexpression in sepsis-induced ALI mice attenuated pulmonary injury, inflammation and apoptosis. Besides, circC3P1 revealed anti-inflammatory and anti-apoptotic effect in MPVEC-treated LPS. CircC3P1 overexpression reduced cell apoptosis and pro-inflammatory cytokines levels via down-regulating miR-21. CircC3P1 attenuated pro-inflammatory cytokine production and cell apoptosis in ALI induced by sepsis through modulating miR-21, indicating that circC3P1 is a promising therapeutic biomarker for sepsis-induced ALI.

Cytosine Methylation Enhances DNA Condensation Revealed by Equilibrium Measurements Using Magnetic Tweezers.

CpG methylation of DNA is common in mammalian cells. In sperm, the DNA has the highest level of CpG methylation and is condensed into toroidal structures. How CpG methylation affects DNA structures and interactions is important to understand its biological roles but is largely unknown. Using an RNA-DNA-RNA structure, we observed the equilibrium hopping dynamics between the condensed and extended states of DNA in the presence of polyamines or polylysine peptide as a reduced model of histone tails. Combing with the measured DNA elasticities, we report that CpG methylation of each cytosine nucleotide substantially increases DNA-DNA attraction by up to 0.2 kBT. For the DNA with 57% GC content, the relative increase caused by CpG methylation is up to 32% for the spermine-induced DNA-DNA attraction and up to 9% for the polylysine-induced DNA-DNA attraction. These findings help us to evaluate the energetic contributions of CpG methylation in sperm development and chromatin regulation.

Opposite Effects of High-Valent Cations on the Elasticities of DNA and RNA Duplexes Revealed by Magnetic Tweezers.

We report that trivalent cobalt hexammine cations decrease the persistence length, stretching modulus, helical density, and size of plectonemes formed under torque of DNA but increase those of RNA. Divalent magnesium cations, however, decrease the persistence lengths, contour lengths, and sizes of plectonemes while increasing the helical densities of both DNA and RNA. The experimental results are explained by different binding modes of the cations on DNA and RNA in our all-atom molecular dynamics simulations. The significant variations of the helical densities and structures of DNA and RNA duplexes induced by high-valent cations may affect interactions of the duplexes with proteins.

[Psychological nursing for genital herpes patients receiving acyclovir plus thymosin and its effect on the incidence of adverse reactions].

OBJECTIVE: To explore the application of psychological nursing in patients with genital herpes receiving acyclovir combined with thymosin and its effect on the incidence of adverse reactions. METHODS: A total of 160 patients with genital herpes treated with acyclovir plus thymosin in our hospital from January 2016 to December 2018 were randomly allocated to receive conventional nursing (the control group, n = 80) and psychological nursing (the trial group, n = 80). Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS) were used to evaluate the anxiety and depression of the patients, and comparisons were made between the two groups of patients in their SAS and SDS scores, the incidence of adverse reactions and their satisfaction with nursing intervention. RESULTS: After nursing intervention, the patients of the trial group, compared with the controls, showed significantly lower SAS scores (39.05 ± 2.97 vs 45.71 ± 3.36, P < 0.01), SDS scores (41.74 ± 2.86 vs 47.28 ± 3.95, P < 0.01), and incidence of adverse reactions (22.50% vs 47.50%, P < 0.05), but a markedly higher rate of satisfaction with nursing intervention (95.00% vs 77.5%, P < 0.01). CONCLUSIONS: Psychological nursing can reduce the incidence of adverse reactions in genital herpes patients receiving acyclovir combined with thymosin and meanwhile improve the mental status of the patients by alleviating their anxiety and depression.

[Yishen Tongluo Recipe combined with minimally invasive surgery for the treatment of varicocele-associated asthenospermia].

OBJECTIVE: To observe the clinical effect of Yishen Tongluo Recipe (YTR) combined with minimally invasive surgery (MIS) in the treatment of varicocele-associated asthenospermia (of the kidney-deficiency and collateral-obstruction type). METHODS: We randomly divided 116 patients with varicocele-associated asthenospermia and up to the inclusion criteria into three groups and treated them by YTR combined with MIS (low spermatic vein ligation at the external inguinal ring orifice under the microscope) (the YTR+MIS group, n = 39), YTR alone (the YTR group, n = 38), or MIS alone (the MIS group, n = 39). At 12 weeks after treatment, we compared the total effectiveness rate, the percentage of progressively motile sperm (PMS), sperm straight line velocity (VSL), sperm DNA fragmentation index (DFI) and symptoms among the three groups of patients. RESULTS: After treatment, the total effectiveness rate was significantly higher in the YTR+MIS than in the YTR and the MIS group (89.74% vs 63.16% and 64.10%, P < 0.05), and so were the percentage of PMS (31.67 ± 3.93 vs 24.48 ± 3.15 and 25.57 ± 3.37, P < 0.05) and VSL (ï¼»30.19 ± 5.32ï¼½ vs ï¼»27.19 ± 5.48ï¼½ and ï¼»27.55 ± 5.24ï¼½ µm/s, P < 0.05), but the DFI was remarkably lower in the former than in the latter two groups (11.25 ± 8.27 vs 15.87 ± 5.45 and 15.26 ± 4.36, P < 0.05). The symptoms were improved more significantly in the YTR+MIS than in the YTR and MIS groups (P < 0.05). CONCLUSIONS: Yishen Tongluo Recipe combined with minimally invasive surgery, as an effective and safe strategy, can significantly improve sperm quality and sperm DNA integrity in patients with varicocele-associated asthenospermia.

S-DNA and RecA/RAD51-Mediated Strand Exchange in Vitro.

S-DNA (stretched DNA) is an elongated base-paired DNA conformation under high tension. Because the RecA/Rad51 family DNA recombinases form helical filaments on DNA and mediate the formation of the DNA triplex (D-loop), in which the DNA is stretched, and because the extension of these nucleoprotein filaments is similar to the extension of S-DNA, S-DNA has long been hypothesized as a possible state of DNA that participants in RecA/Rad51-mediated DNA strand exchange in homologous recombination. Such a hypothesis, however, is still lacking direct experimental studies. In this work, we have studied the polymerization and strand exchange on S-DNA mediated by Escherichia coli RecA, human Rad51, and Saccharomyces cerevisiae Rad51 by single-molecule magnetic tweezers. We report that RecA/Rad51 polymerizes faster on S-DNA than on B-DNA with the same buffer conditions. Furthermore, the RecA/Rad51-mediated DNA triplex forms faster from S-DNA than from B-DNA together with the homologous single-stranded DNA. These results provide evidence that S-DNA can interact with RecA and Rad51 and shed light on the possible functions of S-DNA.

Correlation between C-reactive Protein and Morphology of Aortic Intramural Hematoma on CT Angiography.

Objectives To investigate the morphologic characteristics of intramural hematoma (IMH) on CT angiography (CTA), and evaluate the possible correlation of serum C-reactive protein (CRP) with morphologic characteristics of IMH. Material and Methods Forty-two patients who were initially diagnosed as IMH by aortic CTA and also had serum CRP examination on the same day of CTA were enrolled in this retrospective study, including 30 males and 12 females, with the mean age of 61 ± 14 years old. The volumetric CT data were retrospectively processed and analyzed on post-processing workstation. Based on the thickness of IMH and the length-area curve, the cross-sectional area of true lumen and total vessel were measured, the hematoma-vessel ratio (HVR) was calculated. Imaging characteristics were compared between patients who had pathological elevated CRP (> 0.8 mg/dl) and those did not. Spearman correlation analyses of CRP level and morphological characteristics of IMH were performed, and the receiver operating characteristic (ROC) curve was used to evaluate the diagnostic validity of CRP. Results Of all 42 IMH patients, the mean serum CRP was 3.94 ± 4.71 mg/dl, and the mean HVR was 46.7%± 14.2%. HVR in patients with elevated CRP was significantly higher than those with normal CRP (49.7% ± 15.0% vs. 40.7% ± 10.5 %, P = 0.030). HVR was mildly correlated with CRP in all patients (r =0.48, P < 0.001). CRP levels differed neither between patients with Stanford type A and B (P = 0.207), nor between patients with and without intimal disruption (P = 0.230). To discriminate HVR > 47% (the mean value), the area under curve (AUC) were 0.700 (95% CI: 0.535-0.865) for CRP at a cutoff point of 3.55 mg/dl, with a sensitivity of 54.5% and a specificity of 90.0%. Conclusion CRP was mildly correlated with the severity of cross-sectional hematoma area of IMH, but not with Stanford types and the presence of intimal disruption.

Value of Texture Analysis of Intravoxel Incoherent Motion Parameters in Differential Diagnosis of Pancreatic Neuroendocrine Tumor and Pancreatic Adenocarcinoma.

Objective To evaluate the value of texture features derived from intravoxel incoherent motion (IVIM) parameters for differentiating pancreatic neuroendocrine tumor (pNET) from pancreatic adenocarcinoma (PAC).Methods Eighteen patients with pNET and 32 patients with PAC were retrospectively enrolled in this study. All patients underwent diffusion-weighted imaging with 10 b values used (from 0 to 800 s/mm 2). Based on IVIM model, perfusion-related parameters including perfusion fraction (f), fast component of diffusion (Dfast) and true diffusion parameter slow component of diffusion (Dslow) were calculated on a voxel-by-voxel basis and reorganized into gray-encoded parametric maps. The mean value of each IVIM parameter and texture features [Angular Second Moment (ASM), Inverse Difference Moment (IDM), Correlation, Contrast and Entropy] values of IVIM parameters were measured. Independent sample t-test or Mann-Whitney U test were performed for the between-group comparison of quantitative data. Regression model was established by using binary logistic regression analysis, and receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic efficiency.Results The mean f value of the pNET group were significantly higher than that of the PAC group (27.0% vs. 19.0%, P = 0.001), while the mean values of Dfast and Dslow showed no significant differences between the two groups. All texture features (ASM, IDM, Correlation, Contrast and Entropy) of each IVIM parameter showed significant differences between the pNET and PAC groups (P=0.000-0.043). Binary logistic regression analysis showed that texture ASM of Dfast and texture Correlation of Dslow were considered as the specific imaging variables for the differential diagnosis of pNET and PAC. ROC analysis revealed that multiple texture features presented better diagnostic performance than IVIM parameters (AUC 0.849-0.899 vs. 0.526-0.776), and texture ASM of Dfast combined with Correlation of Dslow in the model of logistic regression had largest area under ROC curve for distinguishing pNET from PAC (AUC 0.934, cutoff 0.378, sensitivity 0.889, specificity 0.854).Conclusions Texture analysis of IVIM parameters could be an effective and noninvasive tool to differentiate pNET from PAC.

[Chest CT Findings of Primary Neuroendocrine Tumor of Thymus:Analysis of 7 Cases].

Objective To explore the clinical features of primary neuroendocrine tumor of thymus (pNET) on computed tomography (CT). Method CT findings and clinical features of 7 patients with pathologically confirmed primary pNET were retrospectively analyzed. Results There were 2 male and 5 female patients aged (52.1±13.3) years,without accompanying endocrine symptoms. Three patients had low-and intermediate-grade pNET and 4 had high-grade pNET. CT showed solid masses in the anterior mediastinum with heterogeneous density,and the average maximum diameter was 6.6 cm. Five patients had necrosis and 4 patients had calcification. After contrast administration,5 cases showed flower ring-like enhancement and 2 cases showed rim enhancement. All lesions showed invasive features,including vessel encompassment (n=5),involvement of surrounding fat space (n=4),involvement of the pleura (n=3),involvement of pericardium (n=2),involvement of chest wall (n=1),direct lung involvement (n=2),lymphadenopathy (n=1),and primary renal neuroendocrine tumor with lung metastasis (n=1). Conclusion pNET is mainly seen in middle-aged people. The typical characteristics of pNET on CT include large mass,calcification,necrosis,and flower ring-like enhancement. CT can clearly display the pNET and the involvement of its surrounding tissues and therefore is helpful for preoperative diagnosis and WHO classification of pNET.