Role of the porous structure of the bioceramic scaffolds in bone tissue engineering

The porous structure of biomaterials plays a critical role in improving the efficiency of biomaterials in tissue engineering. Here we fabricate successfully porous bioceramics with accurately controlled pore parameters, and investigate the effect of pore parameters on the mechanical property, the cell seeding proliferation and the vascularization of the scaffolds. This study shows that the porosity play an important role on the mechanical property of the scaffolds, which is affected not only by the macropores size, but also by the interconnections of the scaffolds. Larger pores are beneficial for cell growth in scaffolds. In contrast, the interconnections do not affect cell growth much. The interconnections appear to limit the number of blood vessels penatrating through adjacent pores, and both the pores size and interconnections can determine the size of blood vessels. The results may be referenced on the selective design of porous structure of biomaterials to meet the specificity of biological application

Original Article Correlation research on ADMA plasma levels and left ventricular function of peritoneal dialysis patients

Abstract: Asymmetric dimethylarginine (ADMA) has been involved in the development mechanism of cardiovascular disease (CVD) in patients with chronic kidney disease. The aim of this study is to investigate the relationship between the plasma ADMA levels and echocardiography, and understand the relationship between ADMA and left ventricular function. All of the patients were divided into three groups, including End-stage renal disease patients on CAPD, Conservative treatment in patients with ESRD and Control group. All the cases in the outpatient clinic or hospital at the next morning were collected fasting venous blood 2 ml. All cases were detected by American GE company Vivid7 Colour Doppler Ultrasonic Echocardiograph to detected left ventricular end-diastolic dimension (LVEDD), Left atrial diameter (LAD), Left ventricular posterior wall thickness in diastole (LVPWT), Interventricular septum thickness in diastole (IVST), left ventricular ejection fraction (LVEF). There were significant differences among all of the three groups for the GFR, urine albumin, SGA, Hb, iPTH and ALB levels. There was statistically significant difference for serum ADMA levels among three groups (F = 34.047, P = 0.000). CAPD patient plasma ADMA levels were negatively correlated with LVEF, and positively correlated with LVMI, LVM, LVEDD, LAD. Conservative treatment group had higher proportion of average artery, left ventricular hypertrophy and left ventricular mass index. The peritoneal dialysis fluid ADMA levels of CAPD patients with peritoneal were positively correlated with LVEF (r = 0.367, P = 0.046), negatively correlated with LVMI. In conclusion, ADMA may be involved in change of left ventricular structure, function, and remodeling process through a complex network

Viruses mobilize plant immunity to deter nonvector insect herbivores.

A parasite-infected host may promote performance of associated insect vectors; but possible parasite effects on nonvector insects have been largely unexplored. Here, we show that Begomovirus, the largest genus of plant viruses and transmitted exclusively by whitefly, reprogram plant immunity to promote the fitness of the vector and suppress performance of nonvector insects (i.e., cotton bollworm and aphid). Infected plants accumulated begomoviral βC1 proteins in the phloem where they were bound to the plant transcription factor WRKY20. This viral hijacking of WRKY20 spatiotemporally redeployed plant chemical immunity within the leaf and had the asymmetrical benefiting effects on the begomoviruses and its whitefly vectors while negatively affecting two nonvector competitors. This type of interaction between a parasite and two types of herbivores, i.e., vectors and nonvectors, occurs widely in various natural and agricultural ecosystems; thus, our results have broad implications for the ecological significance of parasite-vector-host tripartite interactions

3-Chloro-4-hydroxy­furan-2(5H)-one

In the title compound, C4H3ClO3, mol­ecules are linked via O—H⋯O hydrogen bonds into an infinite chain with graph-set motif C(6) along the c axis

Crocin Exhibits Antitumor Effects on Human Leukemia HL-60 Cells In Vitro and In Vivo

Crocin is a carotenoid of the saffron extract that exhibits antitumor activity against many human tumors. However, the effects of crocin on HL-60 cells in vivo have not been evaluated. This study aimed to examine the effects of crocin on HL-60 cells in vitro and in vivo and investigate the underlying mechanisms. HL-60 cells were treated by crocin, and cell proliferation, apoptosis, and cell cycle profiles were examined by MTT assay, AO/EB staining, and flow cytometry, respectively. Furthermore, HL-60 cells were xenografted into nude mice and treated by crocin, the tumor weight and size were calculated, and the expression of Bcl-2 and Bax in xenografts was detected by immunohistochemical staining. The results showed that crocin (0.625–5 mg/mL) inhibited HL-60 cell proliferation and induced apoptosis and cell cycle arrest at G0/G1 phase, in a concentration and time-dependent manner. In addition, crocin (6.25, 25 mg/kg) inhibited the tumor weight and size of HL-60 xenografts in nude mice, inhibited Bcl-2 expression, and increased Bax expression in xenografts. In summary, crocin inhibits the proliferation and tumorigenicity of HL-60 cells, which may be mediated by the induction of apoptosis and cell cycle arrest and the regulation of Bcl-2 and Bax expression

Docosahexaenoic acid has influence on action potentials and transient outward potassium currents of ventricular myocytes

<p>Abstract</p> <p>Background</p> <p>There are many reports about the anti-arrhythmic effects of ω-3 polyunsaturated fatty acids, however, the mechanisms are still not completely delineated. The purpose of this study was to investigate the characteristics of action potentials and transient outward potassium currents (I_to) of Sprague-Dawley rat ventricular myocytes and the effects of docosahexaenoic acid (DHA) on action potentials and I_to.</p> <p>Methods</p> <p>The calcium-tolerant rat ventricular myocytes were isolated by enzyme digestion. Action potentials and I_toof epicardial, mid-cardial and endocardial ventricular myocytes were recorded by whole-cell patch clamp technique.</p> <p>Results</p> <p><b>1.</b> Action potential durations (APDs) were prolonged from epicardial to endocardial ventricular myocytes (<it>P </it>< 0.05). <b>2.</b> I_tocurrent densities were decreased from epicardial to endocardial ventricular myocytes, which were 59.50 ± 15.99 pA/pF, 29.15 ± 5.53 pA/pF, and 12.29 ± 3.62 pA/pF, respectively at +70 mV test potential (<it>P </it>< 0.05). <b>3.</b> APDs were gradually prolonged with the increase of DHA concentrations from 1 μmol/L to 100 μmol/L, however, APDs changes were not significant as DHA concentrations were in the range of 0 μmol/L to 1 μmol/L. <b>4.</b> I_tocurrents were gradually reduced with the increase of DHA concentrations from 1 μmol/L to 100 μmol/L, and its half-inhibited concentration was 5.3 μmol/L. The results showed that there were regional differences in the distribution of action potentials and I_toin rat epicardial, mid-cardial and endocardial ventricular myocytes. APDs were prolonged and I_tocurrent densities were gradually reduced with the increase of DHA concentrations.</p> <p>Conclusion</p> <p>The anti-arrhythmia mechanisms of DHA are complex, however, the effects of DHA on action potentials and I_tomay be one of the important causes.</p

帕金森病认知功能损害的中医药治疗

Parkinson’s disease (PD) is a degenerative disease of the central nervous system that involves many other systems. Cognitive impairment is one of the major presentations of non-motor symptoms of PD. Mild cognitive impairment in Parkinson’s disease (PD-MCI), a predictive factor of the transformation of PD to dementia is a common cognitive defect in PD patients. The effects of traditional Chinese Medicine on cognitive impairment in Parkinson’s disease were valued at home and abroad. Traditional Chinese Medicine has less toxic and side effects, treatment based on syndrome differentiation, and adjustment the balance of Yin and Yang for patients. Combination of Chinese and western medicine treatment could not only reduce the amount of dopamine agents but also counteract the toxic and side effects induced by dopamine agents. Meanwhile, combination of Chinese and western medicine treatment could delay the occurrence and development of cognitive impairment, and has broad application prospect.帕金森病（PD）是一种累及多系统的中枢神经系统变性病。认知功能障碍是PD非运动症状的重要表现形式，大多数PD患者均伴有认知功能损害并最终发展成为痴呆。中医药在帕金森病治疗中的作用越来越受到国内外的重视。中药具有毒副作用小且通过辨证论治、从整体调节患者阴阳平衡的特点，中西医结合治疗既能减少多巴胺制剂用量，又能有效拮抗和治疗西药所引起的毒副作用，延缓认知障碍的发生和发展，具有广阔应用前景

Time-Dependent Spintronic Transport and Current-Induced Spin Transfer Torque in Magnetic Tunnel Junctions

The responses of the electrical current and the current-induced spin transfer torque (CISTT) to an ac bias in addition to a dc bias in a magnetic tunnel junction are investigated by means of the time-dependent nonquilibrium Green function technique. The time-averaged current (time-averaged CISTT) is formulated in the form of a summation of dc current (dc CISTT) multiplied by products of Bessel functions with the energy levels shifted by $m\hbar \omega _{0}$. The tunneling current can be viewed as to happen between the photonic sidebands of the two ferromagnets. The electrons can pass through the barrier easily under high frequencies but difficultly under low frequencies. The tunnel magnetoresistance almost does not vary with an ac field. It is found that the spin transfer torque, still being proportional to the electrical current under an ac bias, can be changed by varying frequency. Low frequencies could yield a rapid decrease of the spin transfer torque, while a large ac signal leads to both decrease of the electrical current and the spin torque. If only an ac bias is present, the spin transfer torque is sharply enhanced at the particular amplitude and frequency of the ac bias. A nearly linear relation between such an amplitude and frequency is observed.Comment: 13 pages,8 figure

ER-α36, a Novel Variant of ER-α, Mediates Estrogen-Stimulated Proliferation of Endometrial Carcinoma Cells via the PKCδ/ERK Pathway

Recently, a variant of ER-α, ER-α36 was identified and cloned. ER-α36 lacks intrinsic transcription activity and mainly mediates non-genomic estrogen signaling. The purpose of this study was to investigate the function and the underlying mechanisms of ER-α36 in growth regulation of endometrial Ishikawa cancer cells.The cellular localization of ER-α36 and ER-α66 were determined by immunofluorescence in the Ishikawa cells. Ishikawa endometrial cancer control cells transfected with an empty expression vector, Ishikawa cells with shRNA knockdown of ER-α36 (Ishikawa/RNAiER36) and Ishikawa cells with shRNA knockdown of ER-α66 (Ishikawa/RNAiER66) were treated with E2 and E2-conjugated to bovine serum albumin (E2-BSA, membrane impermeable) in the absence and presence of different kinase inhibitors HBDDE, bisindolylmaleimide, rottlerin, H89 and U0126. The phosphorylation levels of signaling molecules and cyclin D1/cdk4 expression were examined with Western blot analysis and cell growth was monitored with the MTT assay.Immunofluorescence staining of Ishikawa cells demonstrated that ER-α36 was expressed mainly on the plasma membrane and in the cytoplasm, while ER-α66 was predominantly localized in the cell nucleus. Both E2 and E2-BSA rapidly activated PKCδ not PKCα in Ishikawa cells, which could be abrogated by ER-α36 shRNA expression. E2-and E2-BSA-induced ERK phosphorylation required ER-α36 and PKCδ. However, only E2 was able to induce Camp-dependent protein kinase A (PKA) phosphorylation. Furthermore, E2 enhances cyclin D1/cdk4 expression via ER-α36.E2 activates the PKCδ/ERK pathway and enhances cyclin D1/cdk4 expression via the membrane-initiated signaling pathways mediated by ER-α36, suggesting a possible involvement of ER-α36 in E2-dependent growth-promoting effects in endometrial cancer cells