Alternating wide complex tachycardia after surgical aortic valve replacement

A 51-year-old male developed recurrent episodes of palpitations and pre-syncope after surgical aortic valve replacement. Electrocardiograms after surgery revealed a wide complex tachycardia with alternating left bundle branch and right bundle branch block morphologies. An electrophysiology study (EPS) demonstrated typical bundle branch reentry ventricular tachycardia (BBRVT) treated successfully with right bundle ablation. We demonstrate the key diagnostic features of BBRVT on EPS, describe the circuit of BBRVT with explanation of the HV pseudointerval, and highlight the association of BBRVT and valve replacement.     

2,4-D和干燥处理对谷子成熟胚离体再生体系的影响

谷子离体再生体系不够稳定、转化效率低，已成为谷子功能基因研究和品种改良的瓶颈。为了建立谷子成熟胚稳定的离体再生体系，以当地高产优质的6个谷子品种成熟胚为外植体，以不同2,4-二氯苯氧乙酸（2,4-dichlorophenoxyacetic acid，2,4-D）浓度及对胚性愈伤的不同干燥处理时间为变量，通过单因素实验和正交实验考察各因素对谷子愈伤组织分化及成苗的影响。结果表明，晋谷21在2,4-D浓度为9 μmol·L-1、4 h干燥处理的条件下所建立的再生体系最好，分化率为64.35%，成苗率为29.06%。研究通过探索谷子组织培养的最适条件，为谷子高效稳定遗传转化体系的建立和利用基因工程手段进行品质改良提供了依据。     

A rapid increase in lysophospholipids after geranylgeranoic acid treatment in human hepatoma-derived HuH-7 cells revealed by metabolomics analysis

Geranylgeranoic acid (GGA) was developed as a preventative agent against second primary hepatoma, and was reported to induce cell death in human hepatoma cells via Toll-like receptor 4 (TLR4)-mediated pyroptosis. We recently reported that GGA is enzymatically biosynthesized from mevalonic acid in human hepatoma-derived HuH-7 cells and that endogenous GGA is found in most rat organs including the liver. An unbiased metabolomics analysis of ice-cold 50% acetonitrile extracts from control and GGA-treated cells was performed in this study to characterize the intracellular metabolic changes in GGA-induced pyroptosis and to analyze their relationship with the mechanism of GGA-induced cell death. The total positive ion chromatograms of the cellular extracts in ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry were apparently unchanged after GGA treatment, but an orthogonal partial least squares-discriminant analysis score plot clearly discriminated the intracellular metabolite profiles of GGA-treated cells from that of control cells. S-plot analysis revealed 15 potential biomarkers up-regulated by 24-h GGA treatment according to their variable importance in the projection value of more than 1, and the subsequent metabolomics analysis identified nine of these metabolites as a group of lysophospholipids containing lysophosphatidylcholine with C16:0, C20:4, or C20:3 fatty acids. The possible roles of these lysophospholipids in GGA-induced pyroptosis are discussed.     

A Concise Formula to Compute General Orthogonal Contrast Coefficients

A proof is given of a general formula conjectured by ABT to calculate the values of orthogonal polynomials for the case of nonequidistant levels and unequal numbers of observations. Also, a general derivation of the contrast coefficients is given on the basis of the conditions of orthogonality only. The practicality of the formulae with regard to applications in analysis of variance and regression analysis is stressed.     

Refractory heart failure with LBBB - Pause before CRT

In this report, we describe complete disappearance of LBBB with normalization of LV function in two patients with cardiac sarcoidosis (CS) after immunosuppressive therapy. Both of these patients were ideal Class IA candidates for CRT (Complete LBBB, QRS ≥ 150 ms, EF < 30%). If CS is identified early, immunosuppressive treatment can lead to not only improvement of left ventricular function but also disappearance of the left bundle branch block. Timely diagnosis and management of CS obviated the need of CRT in these patients. It may be reasonable to evaluate all non-ischemic cardiomyopathies for underlying reversible causes prior to CRT implantation.     

Lipid biosynthesis by intact mesophyll and bundle sheath chloroplasts from maize

The two dimorphic forms of chloroplast isolated from maize leaves utilized acetate for fatty acid biosynthesis and had similar requirements for cofactors. The oleate:palmitate ratio of the fatty acid products was lower for bundle sheath chloroplasts as was acetate incorporation into total fatty acids. Galactose from UDP-galactose was incorporated into galactolipids by both morphological forms to give monogalactosyl diacylglycerol and digalactosyl diacylglycerol in the ratio of 4:1.     

Leaf structure in relation to solute transport and phloem loading in Zea mays L.

Small and intermediate (longitudinal) vascular bundles of the Zea mays leaf are surrounded by chlorenchymatous bundle sheaths and consist of one or two vessels, variable numbers of vascular parenchyma cells, and two or more sieve tubes some of which are associated with companion cells. Sieve tubes not associated with companion cells have relatively thick walls and commonly are in direct contact with the vessels. The thick-walled sieve tubes have abundant cytoplasmic connections with contiguous vascular parenchyma cells; in contrast, connections between vascular parenchyma cells and thin-walled sieve tubes are rare. Connections are abundant, however, between the thin-walled sieve tubes and their companion cells; the latter have few connections with the vascular parenchyma cells. Plasmolytic studies on leaves of plants taken directly from lighted growth chambers gave osmotic potential values of about-18 bars for the companion cells and thin-walled sieve tubes (the companion cell-sieve tube complexes) and about-11 bars for the vascular parenchyma cells. Judging from the distribution of connections between various cell types of the vascular bundles and from the osmotic potential values of those cell types, it appears that sugar is actively accumulated from the apoplast by the companion cell-sieve tube complex, probably across the plasmalemma of the companion cell. The thick-walled sieve tubes, with their close spatial association with the vessels and possession of plasmalemma tubules, may play a role in retrieval of solutes entering the leaf apoplast in the transpiration stream. The transverse veins have chlorenchymatous bundle sheaths and commonly contain a single vessel and sieve tube. Parenchymatic elements may or may not be present. Like the thick-walled sieve tubes of the longitudinal bundles, the sieve tubes of the transverse veins have plasmalemma tubules, indicating that they too may play a role in retrieval of solutes entering the leaf apoplast in the transpiration stream.     

牛樟芝固态发酵菌丝体三萜及多糖提取工艺优化研究

为研究牛樟芝固态发酵菌丝体中三萜和多糖的最佳提取工艺，选取浸提时间、料液比和提取温度3个因素，分别设置3个水平，以三萜和多糖得率为指标，并采用正交试验法进行分析。结果表明，三萜的最佳提取工艺条件为：浸提时间3 h、料液比1∶30 (g·mL-1)、温度70 ℃，在此条件下，得率为3.43%；多糖的最佳提取工艺为：浸提时间2 h、料液比1∶20 (g·mL-1)、温度95 ℃，在此条件下得率为4.71%。研究结果为牛樟芝固态发酵菌丝体中三萜和多糖的提取工艺提供了参考。     

Equivalent carbon number-based targeted odd-chain fatty acyl lipidomics reveals triacylglycerol profiling in clinical colon cancer

Odd-chain FAs (OCFAs) are present in very low level at nearly 1% of total FAs in human plasma, and thus, their functions were usually ignored. Recent epidemiological studies have shown that OCFAs are inversely associated with a variety of disease risks. However, the contribution of OCFAs incorporated into complex lipids remains elusive. Here, we developed a targeted odd-chain fatty acyl-containing lipidomics method based on equivalent carbon number and retention time prediction. The method displayed good reproducibility and robustness as shown by peak width at half height within 0.7 min and coefficient of variation under 20%. A total number of 776 lipid species with odd-chain fatty acyl residues could be detected in the ESI mode of reverse-phase LC-MS, of which 309 lipids were further validated using multiple reaction monitoring transitions. Using this method, we quantified odd-chain fatty acyl-containing lipidome in tissues from 12 colon cancer patients, revealing the remodeling of triacylglycerol. The dynamics of odd-chain fatty acyl lipids were further consolidated by the association with genomic and proteomic features of altered catabolism of branched-chain amino acids and triacylglycerol endogenous synthesis in colon cancer. This lipidomics approach will be applicable for screening of dysregulated odd-chain fatty acyl lipids, which enriches and improves the methods for diagnosis and prognosis evaluation of cancer using lipidomics.     

Whole-brain mapping of effective connectivity by fMRI with cortex-wide patterned optogenetics

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