Right ventricular volume and function by three-dimensional echocardiography: results of the echocardiographic measurements in normal Chinese adults (EMINCA) II.

Three-dimensional (3D) echocardiography is an emerging technique for assessing right ventricular (RV) volume and function, but 3D-RV normal values from a large Chinese population are still lacking. The aim of the present study was to establish normal values of 3D-RV volume and function in healthy Chinese volunteers. A total of 1117 Han Chinese volunteers from 28 laboratories in 20 provinces of China were enrolled, and 3D-RV images of 747 volunteers with optimal image quality were ultimately analyzed by a core laboratory. Both vendor-dependent and vendor-independent software platforms were used to analyze the 3D-RV images. We found that men had larger RV volumes than women did in the whole population, even after indexing to body surface area, and older individuals had smaller RV volumes. The normal RV volume was significantly smaller than that recommended by the American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines in both sexes. There were significant differences in 3D-RV measurements between the two vendor ultrasound systems and the different software platforms. The echocardiographic measurements in normal Chinese adults II study revealed normal 3D-RV volume and function in a large Chinese population, and there were significant differences between the sexes, ages, races, and vendor groups. Thus, normal 3D-RV values should be stratified by sex, age, race, and vendor.

The Association Between Sagittal Spinopelvic Alignment and Persistent Low Back Pain After Posterior Lumbar Interbody Fusion for Treatment of Mild L5-S1 Spondylolisthesis: A Retrospective Study.

Introduction: The aim of this study was to explore the association between sagittal spinopelvic alignment and persistent low back pain (PLBP) following posterior decompression and instrumented fusion for mild L5-S1 spondylolisthesis. Methods: By retrieving medical records from January 2015 to April 2020, 200 patients following PLIF for mild L5-S1 spondylolisthesis were retrospectively reviewed. Patients were divided into two groups: PLBP group and non-PLBP group. The baseline characteristics and radiographic parameters were analyzed and compared between groups. Results: The PLBP group comprised 26 patients, and the non-PLBP group comprised 174 patients. No significant differences in preoperative spinopelvic parameters were found between the two groups (p > 0.05). There were statistically significant differences between the preoperative and postoperative variations of LL, SL, LSA, SD, and HOD spinopelvic parameters, regardless of group (p < 0.05). Postoperative PT and SS differed significantly between the PLBP group and non-PLBP group (p < 0.05). In the PLBP group, there were no significant differences between preoperative and postoperative PT; the same applied to SS. However, significant differences were found for the variations in preoperative and postoperative PT and SS between the two groups. The ΔPT was found as an independent risk factor for postoperative PLBP. Conclusion: Patients with mild L5-S1 spondylolisthesis with PLBP after posterior lumbar spinal fusion had decreased SS and increased PT.

The Utility of the Fifth Edition of the BI-RADS Ultrasound Lexicon in Category 4 Breast Lesions: A Prospective Multicenter Study in China.

RATIONALE AND OBJECTIVES: The objective of this study was to evaluate the utility of the fifth edition of the Breast Imaging-Reporting and Data System (BI-RADS) in clinical breast radiology by using prospective multicenter real-time analyses of ultrasound (US) images. MATERIALS AND METHODS: We prospectively studied 2049 female patients (age range, 19-86 years; mean age 46.88 years) with BI-RADS category 4 breast masses in 32 tertiary hospitals. All the patients underwent B-mode, color Doppler US, and US elastography examination. US features of the mass and associated features were described and categorized according to the fifth edition of the BI-RADS US lexicon. The pathological results were used as the reference standard. The positive predictive values (PPVs) of subcategories 4a-4c were calculated. RESULTS: A total of 2094 masses were obtained, including 1124 benign masses (54.9%) and 925 malignant masses (45.1%). For BI-RADS US features of mass shape, orientation, margin, posterior features, calcifications, architectural distortion, edema, skin changes, vascularity, and elasticity assessment were significantly different for benign and malignant masses (p< 0.05). Typical signs of malignancy were irregular shape (PPV, 57.2%), spiculated margin (PPV, 83.7%), nonparallel orientation (PPV, 63.9%), and combined pattern of posterior features (PPV, 60.6%). For the changed or newly added US features, the PPVs for intraductal calcifications were 80%, 56.4% for internal vascularity, and 80% for a hard pattern on elastography. The associated features such as architectural distortion (PPV, 89.3%), edema (PPV, 69.2%), and skin changes (PPV, 76.2%) displayed high predictive value for malignancy. The rate of malignant was 7.4% (72/975) in category 4a, 61.4% (283/461) in category 4b, and 93.0% (570/613) in category 4c. The PPV for category 4b was higher than the likelihood ranges specified in BI-RADS and the PPVs for categories 4a and 4c were within the acceptable performance ranges specified in the fifth edition of BI-RADS in our study. CONCLUSION: Not only the US features of the breast mass, but also associated features, including vascularity and elasticity assessment, have become an indispensable part of the fifth edition of BI-RADS US lexicon to distinguish benign and malignant breast lesions. The subdivision of category 4 lesions into categories 4a, 4b, and 4c for US findings is helpful for further assessment of the likelihood of malignancy of breast lesions.

Biodegradation of dibutyl phthalate by a novel endophytic Bacillus subtilis strain HB-T2 under in-vitro and in-vivo conditions.

The environmental prevalence and potential toxicity of dibutyl phthalate (DBP) motivate the attempt to develop feasible strategies to deal with DBP contamination. In this study, a strain of endphytic bacteria HB-T2 was isolated from sorrel roots and identified as Bacillus sp. by analysing its morphology, physiology, biochemistry and 16S rDNA sequence. The degradation efficiency of DBP by HB-T2 was almost identical under the temperature of 30∼40°C, but was significantly enhanced as the culture pH and inoculum size increases from 6.0 to 8.0, and 1% to 5% respectively. The degradation kinetics of DBP could be well described by the first-order kinetic model, with the degradation half-life ranging from 1.59 to 7.61 h when the initial concentrations of DBP were in the range of 5-20 mg/L. LC-MS analysis of the culture samples taken at varying intervals revealed monobutyl phthalate, phthalic acid and protocatechuic acid as the major metabolic intermediates during the degradation process. HB-T2 exhibited an excellent capability to degrade a wide range of phthalate esters (PAEs), especially butyl benzyl phthalate (BBP), dipentyl phthalate (DPP), and diisobutyl phthalate (DIBP). Inoculation of HB-T2 into Chinese cabbage (Brassica chinensis L.) growing in DBP-contaminated soils could significantly reduce the DBP levels in plant tissues and relieve the phytotoxic effects of DBP. Results of this study highlighted the great potential of this novel endophytic Bacillus subtilis strain HB-T2 for bioremediation of PAEs contamination and improvement of agricultural product safety by reducing PAEs accumulation in edible crops.

Gail Model Improves the Diagnostic Performance of the Fifth Edition of Ultrasound BI-RADS for Predicting Breast Cancer: A Multicenter Prospective Study.

RATIONALE AND OBJECTIVES: The sonographic appearance of benign and malignant breast nodules overlaps to some extent, and we aimed to assess the performance of the Gail model as an adjunctive tool to ultrasound (US) Breast Imaging Reporting and Data System (BI-RADS) for predicting the malignancy of nodules. MATERIALS AND METHODS: From 2018 to 2019, 2607 patients were prospectively enrolled by 35 health care facilities. An individual breast cancer risk was assessed by the Gail model. Based on B-mode US, color Doppler, and elastography, all nodules were evaluated according to the fifth edition of BI-RADS, and these nodules were all confirmed later by pathology. RESULTS: We demonstrated that the Gail model, age, tumor size, tumor shape, growth orientation, margin, contour, acoustic shadowing, microcalcification, presence of duct ectasia, presence of architectural distortion, color Doppler flow, BI-RADS, and elastography score were significantly related to breast cancer (all p < 0.001). The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the curve (AUC) for combining the Gail model with the BI-RADS category were 95.6%, 91.3%, 85.0%, 97.6%, 92.8%, and 0.98, respectively. Combining the Gail model with the BI-RADS showed better diagnostic efficiency than the BI-RADS and Gail model alone (AUC 0.98 vs 0.80, p < 0.001; AUC 0.98 vs 0.55, p < 0.001) and demonstrated a higher specificity than the BI-RADS (91.3% vs 59.4%, p < 0.001). CONCLUSION: The Gail model could be used to differentiate malignant and benign breast lesions. Combined with the BI-RADS category, the Gail model was adjunctive to US for predicting breast lesions for malignancy. For the diagnosis of malignancy, more attention should be paid to high-risk patients with breast lesions.

Deep learning applied to two-dimensional color Doppler flow imaging ultrasound images significantly improves diagnostic performance in the classification of breast masses: a multicenter study.

BACKGROUND: The current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant lesions. In China, breast masses are divided into four categories according to the treatment method: inflammatory masses, adenosis, benign tumors, and malignant tumors. These categorizations are important for guiding clinical treatment. In this study, we aimed to develop a convolutional neural network (CNN) for classification of these four breast mass types using ultrasound (US) images. METHODS: Taking breast biopsy or pathological examinations as the reference standard, CNNs were used to establish models for the four-way classification of 3623 breast cancer patients from 13 centers. The patients were randomly divided into training and test groups (n = 1810 vs. n = 1813). Separate models were created for two-dimensional (2D) images only, 2D and color Doppler flow imaging (2D-CDFI), and 2D-CDFI and pulsed wave Doppler (2D-CDFI-PW) images. The performance of these three models was compared using sensitivity, specificity, area under receiver operating characteristic curve (AUC), positive (PPV) and negative predictive values (NPV), positive (LR+) and negative likelihood ratios (LR-), and the performance of the 2D model was further compared between masses of different sizes with above statistical indicators, between images from different hospitals with AUC, and with the performance of 37 radiologists. RESULTS: The accuracies of the 2D, 2D-CDFI, and 2D-CDFI-PW models on the test set were 87.9%, 89.2%, and 88.7%, respectively. The AUCs for classification of benign tumors, malignant tumors, inflammatory masses, and adenosis were 0.90, 0.91, 0.90, and 0.89, respectively (95% confidence intervals [CIs], 0.87-0.91, 0.89-0.92, 0.87-0.91, and 0.86-0.90). The 2D-CDFI model showed better accuracy (89.2%) on the test set than the 2D (87.9%) and 2D-CDFI-PW (88.7%) models. The 2D model showed accuracy of 81.7% on breast masses ≤1 cm and 82.3% on breast masses >1 cm; there was a significant difference between the two groups (P < 0.001). The accuracy of the CNN classifications for the test set (89.2%) was significantly higher than that of all the radiologists (30%). CONCLUSIONS: The CNN may have high accuracy for classification of US images of breast masses and perform significantly better than human radiologists. TRIAL REGISTRATION: Chictr.org, ChiCTR1900021375; http://www.chictr.org.cn/showproj.aspx?proj=33139.

Reference Values of Carotid Ultrafast Pulse-Wave Velocity: A Prospective, Multicenter, Population-Based Study.

BACKGROUND: Ultrafast ultrasound imaging has been demonstrated to be an effective method to evaluate carotid stiffness through carotid pulse-wave velocity (PWV) with high reproducibility, but a lack of reference values has precluded its widespread use in clinical practice. The aims of this study were to establish reference values of PWV for ultrafast ultrasound imaging in a prospective, multicenter, population-based cohort study and to investigate the main determinants of carotid PWV. METHODS: A total of 1,544 healthy Han Chinese volunteers (581 men [38%]; age range, 18-95 years) were enrolled from 32 collaborating laboratories in China. The participants were categorized by age, blood pressure (BP), and body mass index (BMI). Basic clinical parameters and carotid PWV at the beginning of systole (BS) and at end-systole (ES) were measured using ultrafast ultrasound imaging techniques. RESULTS: PWV at both BS and ES was significantly higher in the left carotid artery than in the right carotid artery. PWV at BS was significantly higher in men than in women; however, no significant difference was noted in PWV at ES between men and women. Multiple linear regression analyses revealed that age, BP, and BMI were independently correlated with PWV at both BS and ES. PWV at BS and ES progressively increased with increases in age, BP, and BMI. Furthermore, age- and sex-specific reference values of carotid PWV for ultrafast ultrasound imaging were established. CONCLUSIONS: Reference values of carotid PWV for ultrafast ultrasound imaging, stratified by sex and age, were determined for the first time. Age, BP, and BMI were the dominant determinants of carotid PWV for ultrafast ultrasound imaging, which should be considered in clinical practice for assessing arterial stiffness.

Risk-predicted dual nomograms consisting of clinical and ultrasound factors for downgrading BI-RADS category 4a breast lesions - A multiple centre study.

Purpose: To develop and to validate a risk-predicted nomogram for downgrading Breast Imaging Reporting and Data System (BI-RADS) category 4a breast lesions. Patients and Methods: We enrolled 680 patients with breast lesions that were diagnosed as BI-RADS category 4a by conventional ultrasound from December 2018 to June 2019. All 4a lesions were randomly divided into development and validation groups at the ratio of 3:1. In the development group consisting of 499 cases, the multiple clinical and ultrasound predicted factors were extracted, and dual-predicted nomograms were constructed by multivariable logistic regression analysis, named clinical nomogram and ultrasound nomogram, respectively. Patients were twice classified as either "high risk" or "low risk" in the two nomograms. The performance of these dual nomograms was assessed by an independent validation group of 181 cases. Receiver Operating Characteristic (ROC) curve and diagnostic value were calculated to evaluate the applicability of the new model. Results: After multiple logistic regression analysis, the clinical nomogram included 2 predictors: age and the first-degree family members with breast cancer. The area under the curve (AUC) value for the clinical nomogram was 0.661 and 0.712 for the development and validation groups, respectively. The ultrasound nomogram included 3 independent predictors (margins, calcification and strain ratio), and the AUC value in this nomogram was 0.782 and 0.747 in the development and validation groups, respectively. In the development group of 499 patients, approximately 50.90% (254/499) of patients were twice classified "low risk", with a malignancy rate of 1.18%. In the validation group of 181 patients, approximately 47.51% (86/181) of patients had been twice classified as "low risk", with a malignancy rate of 1.16%. Conclusions: A dual-predicted nomogram incorporating clinical factors and imaging characteristics is an applicable model for downgrading the low-risk lesions in BI-RADS category 4a and shows good stability and accuracy, which is useful for decreasing the rate of invasive examinations and surgery.

Antimicrobial peptide AR-23 derivatives with high endosomal disrupting ability enhance poly(l-lysine)-mediated gene transfer.

BACKGROUND: pH-sensitive peptides are a relatively new strategy for conquering the poor endosomal release of cationic polymer-mediated transfection. Modification of antimicrobial peptides by exchanging positively-charged residues with negatively-charged glutamic acid residues (Glu) greatly improves its lytic activity at the endosomal pH, which could improve cationic polymer-mediated transfection. METHODS: In the present study, we investigated the effect of the number of Glu substituted for positively-charged residues on the endosomal escape activity of AR-23 and the ability of mutated AR-23 with respect to enhancing cationic polymer-mediated transfection. Three analogs were synthesized by replacing the positively-charged residues in the AR-23 sequence with Glu one-by-one. RESULTS: The pH-sensitive lysis ability of the peptides, the effect of peptides on the physicochemical characteristics, the intracellular trafficking, the transfection efficiency and the cytotoxicity of the polyplexes were determined. Increased lytic activity of peptides was observed with the increased number of Glu replacement in the AR-23 sequence at acidic pH. The number of Glu substituted for positively-charged residues of AR-23 dramatically affects its lysis ability at neutral pH. Triple-Glu substitution in the AR-23 sequence greatly improved poly(l-lysine)-mediated gene transfection efficiency at the same time as maintaining low cytotoxicity. CONCLUSIONS: The results indicate that replacement of positively-charged residues with sufficient Glu residues may be considered as a method for designing pH-sensitive peptides, which could be applied as potential enhancers for improving cationic polymer-mediated transfection.

Can Combined Screening of Ultrasound and Elastography Improve Breast Cancer Identification Compared with MRI in Women with Dense Breasts-a Multicenter Prospective Study.

Objectives: To assess the performance of elastography (ES) and ultrasound (US) in predicting the malignancy of breast lesions and to compare their combined diagnostic value with that of magnetic resonance imaging (MRI). Materials and Methods: The study prospectively enrolled 242 female patients with dense breasts treated in 35 heath care facilities in China between November 2018 and October 2019. Based on conventional US and elastography, radiologists classified the degree of suspicion of breast lesions according to the US Breast Imaging Reporting and Data System (BI-RADS) criteria. The diagnostic value was compared between US BI-RADS and MRI BI-RADS, with pathological results used as the reference standard. Results: The results demonstrated that irregular tumor shape, a nonparallel growth orientation, indistinct margins, angular contours, microcalcifications, color Doppler flow and ES score on US imaging were significantly related to breast cancer in dense breasts (P=0.001; P=0.001; P=0.008; P<0.001; P=0.019; P=0.008; P=0.002, respectively). The sensitivity, specificity, PPV, NPV, accuracy and AUC of US BI-RADS category were 94.7%, 90.7%, 95.8%, 88.0%, 93.4% and 0.93 (95%CI, 0.88-0.97), respectively, while those of MRI BI-RADS category were 98.2%, 57.5%, 84.3%, 83.3%, 86.0% and 0.78 (95%CI, 0.71-0.85), respectively. MRI BI-RADS showed a significantly higher sensitivity than US BI-RADS (98.2% vs 94.7%, P=0.043), whereas US BI-RADS showed significantly higher specificity (90.7% vs 57.5%, P<0.001). US BI-RADS showed better diagnostic efficiency in differentiating nodules in dense breasts than MRI BI-RADS (AUC 0.93 vs 0.78, P<0.001). Conclusion: By combining the use of ES and conventional US, US BI-RADS had better diagnostic efficiency in differentiating nodules in dense breasts than MRI. For the diagnosis of malignant tumors in patients with dense breasts, MRI and US BI-RADS can be used as supplemental diagnostic tools to detect lesions, with US BI-RADS considered the preferred adjunctive resource.

A new antimicrobial peptide isoform, Pc-crustin 4 involved in antibacterial innate immune response in fresh water crayfish, Procambarus clarkii.

The main advantage of antimicrobial peptides (AMPs) used as the effectors in the innate immunity system of invertebrates is that the high specificity is not indispensable. And they play important roles in the systemic defenses against microbial invasion. In this study, a new full-length cDNA of the crustins molecule was identified in red swamp crayfish, P. clarkii (named Pc-crustin 4). The ORF of Pc-crustin 4 contained 369 bp which encoded a protein of 122 amino acids, with a 20-amino-acid signal peptide sequence. On the base of the classification method established by Smith et al., Pc-crustin 4 belonged to Type Ⅰ crustin molecule. The Pc-crustin 4 transcripts were expressed in hemocytes at relatively high level, and relatively low level in hepatopancreas, gills, and intestine in normal crayfish. After respectively challenged with S. aureus or E. ictaluri, the expression levels of Pc-crustin 4 showed up-regulation trends at different degrees in the hemocytes, hepatopancreas, gills, and intestine tissues. Besides, the results of liquid antibacterial assay showed that rPc-crustin 4 inhibited obviously the growth of S. aureus and E. ictaluri. The results of bacteria binding assay showed that rPc-crustin 4 could bind strongly to S. aureus and E. ictaluri. Finally, RNAi assay was performed to study the immunity roles of Pc-crustin 4 in crayfish in vivo. Taken together, Pc-crustin 4 is an important immunity effector molecule, which plays crucial roles in defending against bacterial infection in crayfish.

Prevention of doxorubicin-induced cardiomyopathy using targeted MaFGF mediated by nanoparticles combined with ultrasound-targeted MB destruction.

The present study seeks to observe the preventive effects of doxorubicin-induced cardiomyopathy (DOX-CM) in rats using targeted non-mitogenic acidic fibroblast growth factor (MaFGF) mediated by nanoparticles (NP) combined with ultrasound-targeted MB destruction (UTMD). DOX-CM rats were induced by intraperitoneally injected doxorubicin. Six weeks after intervention, the indices from the transthoracic echocardiography and velocity vector imaging showed that the left ventricular function in the MaFGF-loaded NP (MaFGF-NP) + UTMD group was significantly improved compared with the DOX-CM group. The increased malondialdehyde and decreased superoxide dismutase were observed in the DOX-CM group, while a significant increase in superoxide dismutase and a decrease in malondialdehyde were detected in the groups treated with MaFGF-NP + UTMD. From the Masson staining, the MaFGF-NP + UTMD group showed a significant difference from the DOX-CM group. The cardiac collagen volume fraction and the ratio of the perivascular collagen area to the luminal area number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling positive cells in the MaFGF-NP + UTMD group decreased to 8.9%, 0.55-fold, compared with the DOX-CM group (26.5%, 1.7-fold). From terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling staining, the results showed the strongest inhibition of apoptosis progress in MaFGF-NP + UTMD group. The immunohistochemical staining of the TGF-ß1 in MaFGF-NP + UTMD group reached 3.6%, which was much lower than that of the DOX-CM group (12.6%). These results confirmed that the abnormalities, including left ventricular dysfunction, myocardial fibrosis, cardiomyocytes apoptosis and oxidative stress, could be suppressed by twice weekly MaFGF treatments for 6 consecutive weeks (free MaFGF or MaFGF-NP+/UTMD), with the strongest improvements observed in the MaFGF-NP + UTMD group. Western blot analyses of the heart tissue further revealed the highest pAkt levels, highest anti-apoptosis protein (Bcl-2) levels and strongest reduction in proapoptosis protein (Bax) levels in the MaFGF-NP + UTMD group. This study confirmed the preventive effects of DOX-CM in the rats with MaFGF-NP and UTMD by retarding myocardial fibrosis, inhibiting oxidative stress, and decreasing cardiomyocyte apoptosis.

Does local lavage influence functional recovery during lumber discectomy of disc herniation?: One year's systematic follow-up of 410 patients.

Lumbar disc herniation (LDH) is a common disease and lumbar discectomy is the most common surgical procedure carried out for patients with low back pain and leg symptoms. Although most researchers are focusing on the surgical techniques during operation, the aim of this study is to evaluate the effect of local intervertebral lavage during microdiscectomy.In this retrospective study, 410 patients were operated on by microdiscectomy for LDH during 2011 to 2014. Retrospectively, 213 of them (group A) accepted local intervertebral irrigation with saline water before wound closure and 197 patients (group B) only had their operative field irrigated with saline water. Systematic records of visual analog scores (VAS), Oswestry disability Index (ODI) questionnaire scale scores, use of analgesia, and hospital length of stay were done after hospitalization.The majority (80.49%) of the cases were diagnosed with lumber herniation at the levels of L4/5 and L5/S1. Fifty-one patients had herniations at 2 levels. There were significant decreases of VAS scores and ODI in both groups between preoperation and postoperation of different time points. VAS scores decreased more in group A than group B at early stage of postoperation follow-up. However, there were no statistically significant differences between 2 groups in using analgesia, VAS and ODI up to 1 month of follow-up.Microdiscectomy for LDH offers a marked improvement in back and radicular pain. Local irrigation of herniated lumber disc area could relief dick herniation-derived low back pain and leg radicular pain at early stage of post-operation. However, the pain relief of this intervention was not noticeable for a long period.

A novel single WAP domain-containing protein isoform with antibacterial relevance in Litopenaeus vannamei.

Single WAP domain (SWD)-containing protein is a small protein containing a whey acidic protein (WAP) domain at the C-terminal region. SWD-containing protein exhibits structural similarity to the family of serine proteinase inhibitors. As of this writing, some SWD domain-containing proteins have been identified in crustaceans, and their functions included antibacterial and anti-proteinase activities. We identified a SWD protein isoform gene in Litopenaeus vanname (Lv-SWDi). Very high sequence similarity was found between Lv-SWDi and Lv-SWD. Results of time-course analysis for the gene expression profile showed that Lv-SWDi could produce a rapid feedback and an obvious upregulation at 12 h after Vibrio injection. Endogenous Lv-SWDi protein was obviously upregulated, and the highest expression level was reached at 24 h after Vibrio injection. The purified rLv-SWDi could directly bind to Gram-positive and Gram-negative bacteria. Results of the proteinase inhibitory assay also showed that rLv-SWDi could inhibit secretory protease activity from Bacillus subtilis. Lv-SWDi is a part of an important immunity-relevant gene and may serve important functions in defense against bacteria.

Palladium/norbornene-mediated tandem C-H amination/C-I alkenylation reaction of aryl iodides with secondary cyclic O-benzoyl hydroxylamines and activated terminal olefins.

A novel palladium-catalyzed norbornene-mediated three-component reaction for the construction of ortho-alkenyl aromatic tertiary amines has been achieved, which represents a useful extension of the Catellani-type tandem ortho-selective CH amination transformations.

Controlled synthesis and tunable properties of ultrathin silica nanotubes through spontaneous polycondensation on polyamine fibrils.

This paper describes a facile approach to a biomimetic rapid fabrication of ultrathin silica nanotubes with a highly uniform diameter of 10 nm and inner hollow of around 3 nm. The synthesis is carried out through a spontaneous polycondensation of alkoxysilane on polyamine crystalline fibrils that were conveniently produced from the neutralization of a solution of protonated linear polyethyleneimine (LPEI-H(+)) by alkali compounds. A simple mixing the fibrils with alkoxysilane in aqueous solution allowed for the rapid formation of silica to produce LPEI@silica hybrid nanotubes. These 10-nm nanotubes were hierarchically organized in a mat-like morphology with a typical size of 1-2 micrometers. The subsequent removal of organic LPEI via calcination resulted in silica nanotubes that keep this morphology. The morphology, the structure, the pore properties and the formation mechanism of the silica nanotubes were carefully investigated with scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller measurements (BET), and X-ray diffraction (XRD). Detailed studies demonstrated that the formation of the nanotubes depends on the molar ratio of [OH]/[CH2CH2NH] during the neutralization as well as on the basicity of the alkali compound and on the concentration of the silica source. The synthesis of silica nanotubes established here could be easily applied to a fabrication on the kilogram scale. Silica nanotubes that were obtained from the calcination of hybrid nanotubes of LPEI@silica in an N2 atmosphere showed a distinct photoluminescence centered at 540 nm with a maximum excitation wavelength of 320 nm. Furthermore, LPEI@silica hybrid nanotubes were applied to create silica-carbon composite nanotubes by alternative adsorption of ionic polymers and subsequent carbonization.

Bioinspired synthesis of a soft-nanofilament-based coating consisting of polysilsesquioxanes/polyamine and its divergent surface control.

The synthesis of polysilsesquioxanes coating with controllable one-dimensional nanostructure on substrates remains a major long-term challenge by conventional solution-phase method. The hydrolytic polycondensation of organosilanes in solution normally produces a mixture of incomplete cages, ladderlike, and network structures, resulting in the poor control of the formation of specific nanostructure. This paper describes a simple aqueous process to synthesize nanofilament-based coatings of polysilsesquioxanes possessing various organo-functional groups (for example, thiol, methyl, phenyl, vinyl, and epoxy). We utilized a self-assembled nanostructured polyamine layer as a biomimetically catalytic scaffold/template to direct the formation of one-dimensional nanofilament of polysilsesquioxanes by temporally and spatially controlled hydrolytic polycondensation of organosilane. The surface nanostructure and morphology of polysilsesquioxane coating could be modulated by changing hydrolysis and condensation reaction conditions, and the orientation of nanofilaments of polysilsesquioxanes on substrates could be controlled by simply adjusting the self-assembly conditions of polyamine layer. The nanostructure and polyamine@polysilsesquioxane hybrid composition of nanofilament-based coatings were examined by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The template role of nanostructured polyamine layer for the formation of polysilsesquioxane nanofilament was confirmed by combining thin film X-ray diffraction (XRD) and XPS measurements. Moreover, these nanotextured coatings with various organo-functional groups could be changed into superhydrophobic surfaces after surface modification with fluorocarbon molecule.

Direct generation of silica nanowire-based thin film on various substrates with tunable surface nanostructure and extreme repellency toward complex liquids.

We report our new achievement on the direct generation of linear polyethylenimine@silica hybrid and silica thin films on various substrates, which is composed of 10 nm nanowire silica structure with tunable micro/nano hierarchical surface morphology. We found that a process for the rapid and controlled self-assembly of crystalline template layer of linear polyethylenimine on substrate surface is critical for the formation of ultrathin silica nanowire structure and micro/nano hierarchical morphology, since the template linear polyethylenimine layer directly promotes the hydrolytic condensation of alkoxysilanes. Templated silica mineralization on the self-assembled linear polyethylenimine layer was confirmed by the studies of X-ray photoelectron spectroscopy (XPS) and thin film X-ray diffraction (XRD). The surface of silica nanostructure and hierarchy could be well controlled by simply adjusting the conditions for LPEI assembly, such as the polymer concentrations and substrate surface property. After a simple fluorocarbon modification, the hierarchical silica nanowire thin film demonstrated robust and reliable super-repelling property toward a series of aqueous liquids (such as commercial inkjet (IJ) ink, soy source, milk). Comparative studies clearly confirmed the critical importance of surface hierarchy for enhancing super-repelling property. Moreover, we found that the forcibly formed dirty sports (both wet and dry) from the complexly composed liquids on the super-antiwetting surface could be easily and completely cleaned by simple water drop flow. We expect these tailored nanosurfaces would have the potentials for practical technological applications, such as liquid transferring, self-cleaning, microfluid, and biomedical-related devices.

The use of MRI apparent diffusion coefficient (ADC) in monitoring the development of brain infarction.

BACKGROUND: To study the rules that apparent diffusion coefficient (ADC) changes with time and space in cerebral infarction, and to provide the evidence in defining the infarction stages. METHODS: 117 work-ups in 98 patients with cerebral infarction (12 hyperacute, 43 acute, 29 subacute, 10 steady, and 23 chronic infarctions) were imaged with both conventional MRI and diffusion weighted imaging. The average ADC values, the relative ADC (rADC) values, and the ADC values or rADC values from the center to the periphery of the lesion were calculated. RESULTS: The average ADC values and the rADC values of hyperacute and acute infarction lesion depressed obviously. rADC values in hyperacute and acute stage was minimized, and increased progressively as time passed and appeared as "pseudonormal" values in approximately 8 to 14 days. Thereafter, rADC values became greater than normal in chronic stage. There was positive correlation between rADC values and time (P < 0.01). The ADC values and the rADC values in hyperacute and acute lesions had gradient signs that these lesions increased from the center to the periphery. The ADC values and the rADC values in subacute lesions had adverse gradient signs that these lesions decreased from the center to the periphery. CONCLUSION: The ADC values of infarction lesions have evolution rules with time and space. The evolution rules with time and those in space can be helpful to decide the clinical stage, and to provide the evidence in guiding the treatment or judging the prognosis in infarction.

Molecular characterization of hepcidin AS-hepc2 and AS-hepc6 in black porgy (Acanthopagrus schlegelii): expression pattern responded to bacterial challenge and in vitro antimicrobial activity.

There are more diversified isoforms of the hepcidin gene that exist in fishes than in mammals, and elucidating the differences between these isoforms should provide insight into the functioning of hepcidin in fishes. In our study, AS-hepc2 and AS-hepc6 hepcidin isoforms from black porgy were characterized for their in vivo expression patterns following bacterial challenge, and their in vitro antimicrobial activities against Gram-positive and Gram-negative bacteria as well as fungi. As a result, two isoforms were observed to be widely distributed in all the tissues tested. AS-hepc2 was a liver-expressed hepcidin peptide which was always highly more expressed in the liver than in the other tissues tested no matter whether this was before or after bacterial challenge. AS-hepc6 was detected mainly in the head kidney and trunk kidney of normal fish, but, in the challenged fish, its expression involved more tissues than just the kidneys. The mature peptides of AS-hepc2 and AS-hepc6 were modeled for 3D structure and then synthesized for antimicrobial assay. AS-hepc6 had a wider antimicrobial spectrum than AS-hepc2 and, in particular, had more potent antifungal activity. Our study indicated that the two hepcidin isoforms had different characteristics in terms of their expression patterns and antimicrobial activity, and they were assumed to play an overlapping role in the innate immune system of black porgy against invading pathogens.