[Cardioversion efficacy of nifekalan in patients with sustained atrial fibrillation after radiofrequency ablation].

Objective: To evaluate the efficacy and safety of nifekalan (NIF) on cardioversion in atrial fibrillation (AF) patients post radiofrequency ablation, and investigate the relevant factors related to the cardioversion efficacy of NIF. Methods: We screened patients with sustained AF rhythm after radiofrequency ablation between November 2016 and July 2018. Participants were treated with intravenous NIF 0.4 mg/kg within 5-10 minutes after ablation. We observed the adverse reaction, and monitored the rhythm, heart rate, QT interval and QTc interval before the medication and at 5, 10, 20, 120 min after the medication. According to the drug outcome of NIF, patients were divided into conversion group and non-conversion group, related factors affecting conversion efficacy were evaluated using logistic regression analysis. Results: (1)A total of 116 patients were enrolled in the study (63 males and 53 females, mean age was (64±18) years). Among them, 72 patients were converted to sinus rhythm, and the overall successful rate was 62.1%. There were 84 patients with persistent AF, of which 50 cases (59.2%) were restored to sinus rhythm. There were 32 patients with paroxysmal AF, 22 cases (68.8%) of them were restored to sinus rhythm. The conversion time was 1.5 to 12 (6.8±3.4)min. (2) In 116 patients, the QT interval and QTc interval were significantly longer after medication than before the drug administration (P<0.01), and peaked at about 10th min, and restored to the level before drug administration at about 120th min. (3) There were 8 cases of bradycardia (6.9%), 3 cases of frequent and short ventricular tachycardia (2.6%). (4) The duration of atrial fibrillation was shorter and left atrial diameter was smaller in the cardioversion group than in the non-cardioversion group (both P<0.05). There were no significant differences in gender, disease history, atrial fibrillation type and structural heart disease between the two groups (P>0.05). (5) Multifactorial logistic regression analysis showed that the duration of atrial fibrillation (OR=0.980, 95%CI 0.966-0.994, P=0.004) and the left atrial diameter (OR=0.888, 95%CI 0.814-0.967, P=0.007) were the factors that influence the cardioversion efficacy of NIF on atrial fibrillation post ablation. Conclusions: The total effective rate of NIF was 62.1% in patients witrh sustained AF post radiofrequency ablation, was 68.8% in patients with paroxysmal AF. Besides, NIF has the advantage of short conversion time and few adverse reactions. Left atrium diameter and AF duration were relevant factors that influence the efficacy of NIF of cardioversion in patients with sustained AF after radiofrequency ablation.

[Recurrent syncope related to catecholaminergic polymorphic ventricular tachycardia due to de novo RyR2-R2401H mutation].

Objective: To explore the clinical and molecular genetic features of a Chinese patient with catecholaminergic polymorphic ventricular tachycardia (CPVT). Methods: Clinical data including resting electrocardiography, echocardiography and treadmill exercise testing of a patient with CPVT admitted to our department in March 2013 were analyzed, and the peripheral venous blood samples of the patient and his family members and 400 ethnicity-matched healthy controls were obtained. All exons and exon-intron boundaries of the six CPVT-related genes including RYR2, CASQ2, TRDN, CALM1, KCNJ2 and ANKB were sequenced to detect the variants related to CPVT. The relationship between the genotypes and phenotypes was analyzed to direct the target therapy. Results: Recurrent syncope induced either by exercise or extreme frightened fear was observed in this patient. There was no positive family history of syncope or sudden death. The resting electrocardiography and echocardiography of the patient were normal, while the exercise testing revealed bidirectional and polymorphic ventricular tachycardia. A cardiac ryanodine receptor gene mutation (R2401H) was identified in this patient, while this mutation was absent in his parents and sister and 400 controls. No variant was detected in the remaining five candidate genes. Treatment with high dose of metoprolol succinate (118.75 mg/d) was effective and patient was free of syncopal attack during the 2 years follow-up. Conclusion: This is the first report on RyR2-R2401H mutation in Chinese patient with CPVT, and high dose of metoptolol is the effective therapy option for CPVT related to RyR2 mutation.

[Evaluation of effect based on different typing methods in Escherichia coli].

Objective: To evaluate the typing and clinical application effect based on clustered regularly interspaced short palindromic repeats (CRISPRs), serotype, and Multilocus Sequence Typing (MLST). Methods: The spacers, serotype and sequence type (ST) were obtained with CRISPRsFinder, SeroTypeFinder and MLST. PCR was used to amplify the CRISPRs, and the spacers were used to predict serotype and ST, then comparing with the serotype and ST. Results: We defined the I-E CRISPR/Cas as CT-Ⅰ, I-F CRISPR/Cas as CT-Ⅱ, and only CRISPR3-4 as CT-Ⅲ. We designated each unique arrangement spacer profile as a unique CRISPRs type. A total of 79 CT types, 76 serotypes, and 66 STs were identified. The CRISPRs typing was the most discriminating, with the Simpson index of 0.936, having the highest correlation with serology with the adjusted Rand index of 0.908. The CRISPRs type could divide the same serotype (ST) into two subtypes [O157∶H7(ST11), O104∶H4(ST678), and O26∶H11(ST21)]. The detection rates of CRISPR1, CRISPR2, CRISPR3, CRISPR4, and CRISPR3-4 were 81.1%, 94.5%, 1.4%, 1.4%, and 4.6%, with the accuracy rate of 95.0% and 100.0% according to the spacers to forecast O157∶H7 (ST11) and ST131. Conclusion: Based on the CRISPRs spacer, this method can be used as an essential molecular typing for E.coli, as it presents a good typing and clinical application effect.

In vivo measurement of the subchondral bone thickness of lumbar facet joint using magnetic resonance imaging.

OBJECTIVE: To measure in vivo thicknesses of the facet joint subchondral bone across genders, age groups, with or without low back pain symptom groups and spinal levels. METHODS: Lumbar (L1-L2 to L5-S1) magnetic resonance (MR) imaging was performed in 81 subjects (41 males and 40 females, mean age 37.6 years). Thicknesses of the subchondral bone were measured in 1620 facet joints using the MR images with custom-written image processing algorithms together with a multi-threshold segmentation technique using each facet joint's middle axial-slice. This method was validated with 12 cadaver facet joints, scanned with both MR and micro-computed tomography images. RESULTS: An overall average thickness value for the 1620 analyzed joints was measured as 1.56±0.01 mm. The subchondral bone thickness values showed significant increases with successive lower spinal levels in the subjects without low back pain. The facet joint subchondral bone thickness in asymptomatic females was much smaller than in asymptomatic males. Mean subchondral bone thickness in the superior facet was greater than that in the inferior facet in both female and male asymptomatic subjects. CONCLUSIONS: This study is the first to quantitatively show subchondral bone thickness using a validated MR-based technique. The subchondral bone thickness was greater in asymptomatic males and increased with each successive lower spinal level. These findings may suggest that the subchondral bone thickness increases with loading. Furthermore, the superior facet subchondral bone was thicker than the inferior facet in all cases regardless of gender, age or spinal level in the subjects without low back pain. More research is needed to link subchondral bone microstructure to facet joint kinematics and spinal loads.

[Clinical application of thoracodorsal artery perforator flaps in the repair of head and neck defects].

Objective: To analyse the clinical application of thoracodorsal artery perforator flaps (TDAPF) in the repair of head and neck defects. Methods: A retrospective review was conducted on 38 patients with oral and maxillofacial head and neck malignant tumors who underwent radical resection of oral and oropharyngeal carcinoma and TDAPF repair in the Department of Oral and Maxillofacial Head and Neck Oncology of the Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from June 2017 to November 2018. Among them, 32 were males and 6 were females, aged 30-74 years. Flap size, vessel pedicle length, diameter and number of perforators, and flap fat thickness were recorded and counted. Elasti Meter and Skin Fibro Meter were applied to measure the skin elasticity and hardness in the donor areas of 4 kinds of skin flaps before the flap preparation. SPSS 19.0 statistical software was used for statistical analysis of the data. Results: All the flaps survived (100%). The mean elasticity of TDAPF [(41.2±12.9) N/m] was significantly lower than that of anterolateral thigh [(77.6±23.3) N/m, χ²=88.89, P<0.05], anterolateral thigh [(62.6±17.7) N/m, χ²=59.99, P<0.05] and or forearm flap [(51.7±8.6) N/m, χ²=37.82, P<0.05]. The hardness of TDAPF [(0.037±0.016) N] was also significantly lower than that of anterolateral femoral [(0.088±0.019) N, F=93.27, P<0.05], anteromedial femoral [(0.059±0.020) N, F=25.71, P<0.05] or forearm flap [(0.062±0.016) N, F=29.11, P<0.05]. Follow-up period ranged from 2 to 14 months. The 38 patients treated with TDAPF had a good recovery of the functions in the recipient areas, and the scars of the donor areas were not obvious after surgery, without serious complications. Conclusion: TDAPF is suitable for reconstruction of head and neck defect, with ductile texture and good recovery of the morphology and function of head and neck.

Stimulation of the sacral nerve reduces gut bacterial translocation and endotoxemia caused by acute spinal cord injury in rabbits.

Study design:Disturbance of gastrointestinal motility following acute spinal cord injury complicated with paraplegia can lead to bacterial overgrowth in the gastrointestinal tract, and increase the incidence of bacterial translocation. Experiments in a New Zealand rabbit model of acute spinal cord injury were performed.Objective:This study was designed to determine if the electrical stimulation of the sacral nerve prevents gut-origin bacterial translocation and endotoxemia in an animal model of acute spinal cord injury.Settings:Xiangya Hospital, Central South University, Hunan, PR China.Methods:New Zealand rabbits were divided into three groups: Control group, Paraplegic Vehicle group without sacral nerve stimulation and Paraplegic Experiment group with sacral nerve stimulation. Blood and multiple organs were collected for bacterial cultures and endotoxin determination at 24, 48 and 72 h following spinal cord injury. The histology and ultra-structural features of the organs were studied.Results:Bacterial translocation and endotoxemia were observed in all animals with acute spinal cord injury. Sacral nerve stimulation increased defecation, decreased endotoxin levels and bacterial translocation and improved the morphology of the organs.Conclusion:After acute spinal cord injury, stimulation of the sacral nerve reduced gut bacterial translocation and endotoxemia.Spinal Cord advance online publication, 6 April 2010; doi:10.1038/sc.2010.35.

Direct Observation of Microscopic Inhomogeneities with Energy-Dispersive Diffraction of Synchrotron-Produced X-rays.

Evidence of structural inhomogeneities in two high-transition-temperature superconductors, YBa(2)Cu(3)O(7-delta) and Nd2-xCexCuO4-y, is presented. When samples were illuminated by highly collimated x-rays produced on a synchrotron wiggler, small changes in the lattice were detected over a spatial scale of 10 micrometers. These changes are interpreted as evidence of variations in the oxygen content in one case and in the cerium content in the other; both affect the superconducting properties. The existence of such structural inhomogeneities brings into question whether exotic experimental results obtained from superconducting materials with high transition temperatures actually reflect intrinsic properties.

Role of a two-step suture in the prevention of postoperative transoral salivary fistulas during reconstruction of the oral cavity.

Transoral salivary fistulas are one of the most serious postoperative complications after operations for oral cancer, and we propose a new, two-step suture method to avoid them. From January 2005 to September 2017, 240 patients were recruited at the Shanghai Ninth People's Hospital and divided into experimental (n=89) or control (n=151) groups. The experimental group was treated by a two-step suture technique, while the control group had conventional sutures. Statistical differences were assessed using the chi squared and t tests, as appropriate. Only two patients developed transoral salivary fistulas in the experimental group, while in the control group there were 14 (9%). The incidence of fistulas in the experimental group was significantly lower than that in the control group (p=0.035). Regression analysis showed that there was a significant correlation between the groups and the incidence of salivary fistulas (p=0.032). The two-step suture technique is safe, effective, and easy to learn, and could reduce the incidence of postoperative salivary fistulas.

MiR-181d promotes steroid-induced osteonecrosis of the femoral head by targeting SMAD3 to inhibit osteogenic differentiation of hBMSCs.

OBJECTIVE: We aimed to investigate whether miR-181d may be involved in steroid-induced osteonecrosis of the femoral head (ONFH) and its underlying mechanism. PATIENTS AND METHODS: Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-181d in bone marrow of 5 cases of steroid-induced femoral head necrosis and 5 cases of femoral head necrosis secondary to femoral neck fractures. Marrow-derived mesenchymal stem cells (MSCs) were obtained from bone marrow samples and identified. Subsequently, the effects of miR-181d on osteogenic differentiation were evaluated by alizarin red staining and alkaline phosphatase. Meanwhile, qRT-PCR was performed to detect the levels of osteoblast-specific genes. RESULTS: The expression of miR-181d in the bone marrow of patients with steroid-induced osteonecrosis of the femoral head was significantly higher than that in the control group. When the expression of miR-181d in MSCs was upregulated, the ALP staining became lighter and the number of calcified nodules, as well as the expression of osteoblast-specific genes, decreased significantly. Meanwhile, the opposite results were observed when miR-181d expression was inhibited. Western blot and luciferase reporting assay proved that miR-181d could negatively regulate the expression of SMAD3. CONCLUSIONS: MiR-181d can inhibit the differentiation of hBMSCs into osteoblasts by regulating the expression of SMAD3.

Diamond anvil cell radial x-ray diffraction program at the National Synchrotron Light Source.

During the past decade, the radial x-ray diffraction method using a diamond anvil cell (DAC) has been developed at the X17C beamline of the National Synchrotron Light Source. The detailed experimental procedure used with energy dispersive x-ray diffraction is described. The advantages and limitations of using the energy dispersive method for DAC radial diffraction studies are also discussed. The results for FeO at 135 GPa and other radial diffraction experiments performed at X17C are discussed in this report.

1H NMR Metabolomics Study of Spleen from C57BL/6 Mice Exposed to Gamma Radiation.

Due to the potential risk of accidental exposure to gamma radiation, it's critical to identify the biomarkers of radiation exposed creatures. In the present study, NMR based metabolomics combined with multivariate data analysis to evaluate the metabolites changed in the C57BL/6 mouse spleen after 4 days whole body exposure to 3.0 Gy and 7.8 Gy gamma radiations. Principal component analysis (PCA) and orthogonal projection to latent structures analysis (OPLS) are employed for classification and identification potential biomarkers associated with gamma irradiation. Two different strategies for NMR spectral data reduction (i.e., spectral binning and spectral deconvolution) are combined with normalize to constant sum and unit weight before multivariate data analysis, respectively. The combination of spectral deconvolution and normalization to unit weight is the best way for identifying discriminatory metabolites between the irradiation and control groups. Normalized to the constant sum may achieve some pseudo biomarkers. PCA and OPLS results shown that the exposed groups can be well separated from the control group. Leucine, 2-aminobutyrate, valine, lactate, arginine, glutathione, 2-oxoglutarate, creatine, tyrosine, phenylalanine, π-methylhistidine, taurine, myoinositol, glycerol and uracil are significantly elevated while ADP is decreased significantly. These significantly changed metabolites are associated with multiple metabolic pathways and may be potential biomarkers in the spleen exposed to gamma irradiation.

The effect of estrogen-related receptor α on the regulation of angiogenesis after spinal cord injury.

Estrogen receptor-related receptor-α (ERRα) is an orphan member of the nuclear receptor superfamily that interacts with peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) to stimulate vascular endothelial growth factor (VEGF) expression and angiogenesis in a hypoxia-inducible factor-1α-independent pathway. Although it is not regulated by any natural ligand, the action of ERRα can be blocked by the synthetic molecule XCT790. In the present study, Sprague-Dawley rats were randomly allocated to a sham group, injury-saline group or injury-XCT90 group. A modified Allen's weight-drop method was applied to induce the acute traumatic spinal cord injury (SCI) model in these rats, and an injection of XCT790 was administered every 24h, starting half an hour after the SCI contusion. Histological analyses revealed that XCT790 significantly aggravated tissue damage and decreased the number of ERRα-positive cells at 1, 3 and 7 days after SCI. Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) analyses also indicated that XCT790 dramatically repressed the expression of ERRα, thus reducing the expression of VEGF and angiopoietin-2 (Ang-2) throughout the duration of the experiment, but the expression of PGC-1α was not affected. Immunofluorescence analyses indicated that vascular density and endothelial cell proliferation were decreased in the injury-XCT90 group compared with the injury-saline group. These results suggest that ERRα is involved in mediating angiogenesis after SCI in the rat traumatic SCI model.

A high-resolution (13)C 3D CSA-CSA-CSA correlation experiment by means of magic angle turning.

It is shown in this paper that a previously reported 90 degrees sample flipping (13)C 2D CSA-CSA correlation experiment may be carried out alternatively by employing constant slow sample rotation about the magic angle axis and by synchronizing the read pulse to 13 of the rotor cycle. A high-resolution 3D CSA-CSA-CSA correlation experiment based on the magic angle turning technique is reported in which the conventional 90 degrees 2D CSA-CSA powder pattern for each carbon in a system containing a number of inequivalent carbons may be separated according to the isotropic chemical shift value. The technique is demonstrated on 1,2,3-trimethoxybenzene in which all of the overlapping powder patterns that cannot be segregated by the 2D CSA-CSA experiment are resolved successfully by the 3D CSA-CSA-CSA experiment, including even the two methoxy groups (M(1) and M(3)) whose isotropic shifts, confirmed by high-speed MAS, are separated by only 1 ppm. A difference of 4 ppm in the principal value component (delta(33)) between M(1) and M(3) is readily obtained.

A novel dipolar dephasing method for the slow magic angle turning experiment.

Complete suppression of the resonances from protonated carbons in a slow magic angle spinning experiment can be achieved using five dipolar dephasing (Five-DD) periods distributed in one rotor period. This produces a spectrum containing only the spinning sidebands (SSB) from the nonprotonated carbons. It is shown that the SSB patterns corresponding to the nonprotonated carbons are not distorted over a wide range of dipolar dephasing times. Hence, this method can be used to obtain reliable principal values of the chemical shift tensors for each nonprotonated carbon. The Five-DD method can be readily incorporated into isotropic-anisotropic 2D experiments such as FIREMAT and 2D-PASS to facilitate the measurement of the (13)C chemical shift tensors in complex systems.

Modified spectral editing methods for (13)C CP/MAS experiments in solids.

The spectral editing approach of Zilm and coworkers utilizes polarization, polarization inversion, and spin depolarization methods for enhancing or suppressing NMR spectral lines in solids. The proposed pulse sequences allow nonprotonated C, CH, CH(2), and CH(3) types of carbon resonances to be separated from one another and identified accordingly. The former method tentatively separates the nonprotonated C and CH(3) peaks with a cutoff shift of 35 ppm. This shift is a reasonable demarcation shift for a preponderance of organic molecules, but exceptions do exist that could constitute a serious drawback in a few instances. The new approach separates the nonprotonated C and CH(3) carbon peaks unequivocally using modified pulse sequences similar to those of Zilm. Further, both the CH only and CH(2) only spectra, respectively, can be acquired directly from combining so called (+) and (-) sequences using different spectral delay periods and pulse parameters. The (+) and the (-) pulse sequences produce signals for the nonprotonated and methyl carbons that have essentially the same amplitude but opposite phases. These spectra, combined with the previously reported CH(3) and nonprontonated C only spectra, offer a complete spectral editing technique for solid samples. Examples of these spectral editing methods are provided for 3-methylglutaric acid, fumaric acid monoethyl ester, and two complex natural products: methyl o-methylpodocarpate and 10-deacetylbaccatin III.

Technique for importing greater evolution resolution in multidimensional NMR spectrum.

A very simple and general procedure that extracts constant-evolution-frequency data from a truncated multidimensional (2D, 3D, 4D, etc.) FID is described, generalized, analyzed, and illustrated. The method replaces Fourier transformation of the evolution dimension with a linear model created from a separate, high-quality 1D FID. The equivalent of high resolution in the evolution dimension can be achieved without obtaining an extensive multidimensional FID. The analysis of the 1D FID can also be used to predict the signal to noise ratio of the extracted slices that will result from various evolution dimension sampling protocols, making it possible to develop a priori an optimal sampling strategy for the multidimensional FID. The evolution dimension need not be sampled periodically. The procedure has a potential signal-to-noise ratio advantage because it extracts usable information from a multidimensional FID at short evolution times before the magnetization has decayed significantly.

1H dynamic nuclear polarization in supercritical ethylene at 1.4 T.

(1)H dynamic nuclear polarization (DNP) has been measured in supercritical ethylene in the pressure range 60-300 bar in an external field of 1.4 T. A single-cell sapphire tube was used as a high-pressure cell, and powdered 1,3-bisdiphenylene-2-phenyl allyl (BDPA) free radicals were added and distributed at the wall of the cell. At all pressures the dominant DNP mechanism was a positive Overhauser enhancement, caused by proton-electron contact interactions at the fluid/solid radical interface. The observed enhancements varied from 12 at 60 bar to 17 at 300 bar. Besides the Overhauser enhancement, small solid state and thermal mixing enhancements also were observed, indicating that part of the ethylene was adsorbed at the radical surface for a prolonged time. The impacts of the experimental conditions on the Overhauser enhancement factors are discussed, and enhancements of at least 40-60 are estimated when the EPR saturation factor and the leakage factor become maximal. These data indicate that DNP-enhanced NMR has the potential of extending the impact of NMR in research areas involving supercritical fluids.

A new staining method for constriction marks in skin.

A modified Poley's acid fuchsin-methyl green stain was used to demonstrate ligature marks in tissues taken at autopsy. This stain was compared in 30 cases with haematoxylin-eosin, Mallory's trichrome and Ogata's picro-indigocarmine stains. Using the modified Poley method, it was possible to demonstrate the compression mark in corpses even when post-mortem changes were advanced. The method was found useful in evaluating the cases when the force used was minimal or when the mark was atypical using the usual haematoxylin-eosin method.

[Fibrobronchoscopy in the diagnosis of middle lobe syndrome].

236 cases with middle lobe syndrome were examined with fibrobronchoscope. The total rate of positive finding was 92.8% (219/236). Inflammation (167 cases), lung cancer (47 cases), tuberculosis (17 cases) accounted for most of the cases. The diagnostic rate for the three above-mentioned diseases were 97.6%, 87.2% and 58.8% respectively. Fibrobronchoscopy was also of significant diagnostic value in determining other uncommon cases such as broncholithiasis, lipoid pneumonia, lung infiltration in leukemia, etc. The etiology, chest X-ray (including CT) presentations of this middle lobe syndrome and the diagnostic value of fibrobronchoscopy were discussed. Our experience suggests that this procedure is both safe and effective in the diagnosis of patients with middle lobe syndrome.