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991.
992.
Sonia Baig Narasimhan Kothandaraman Jayapal Manikandan Li Rong Kim Huey EE Jeffrey Hill Chin Wee Lai Wan Yu Tan Felicia Yeoh Anita Kale Lin Lin Su Arijit Biswas Sheila Vasoo Mahesh Choolani 《Clinical proteomics》2014,11(1)
Background
Placental syncytiotrophoblast microvesicles (STBM) are shed into the maternal circulation during normal pregnancy. STBM circulate in significantly increased amounts in preeclampsia (PE) and are considered to be among contributors to the exaggerated proinflammatory, procoagulant state of PE. However, protein composition of STBM in normal pregnancy and PE remains unknown. We therefore sought to determine the protein components of STBM and whether STBM protein expressions differ in preeclamptic and normal pregnancies.Patients with PE (n = 3) and normal pregnant controls (n = 6) were recruited. STBM were prepared from placental explant culture supernatant. STBM proteins were analyzed by a combination of 1D Gel-LC-MS/MS. Protein expressions levels were quantified using spectral counts and validated by immunohistochemistry.Results
Over 400 proteins were identified in the STBM samples. Among these, 25 proteins were found to be differentially expressed in preeclampsia compared to healthy pregnant controls, including integrins, annexins and histones.Conclusion
STBM proteins include those that are implicated in immune response, coagulation, oxidative stress, apoptosis as well as lipid metabolism pathways. Differential protein expressions of STBM suggest their pathophysiological relevance in PE.Electronic supplementary material
The online version of this article (doi:10.1186/1559-0275-11-40) contains supplementary material, which is available to authorized users. 相似文献993.
Jingwei Sheng Winston Shim Jun Lu Sze Yun Lim Boon Hean Ong Tien Siang Lim Reginald Liew Yeow Leng Chua Philip Wong 《Journal of cellular and molecular medicine》2014,18(2):355-362
Telocytes (TCs) with exceptionally long cellular processes of telopodes have been described in human epicardium to act as structural supporting cells in the heart. We examined myocardial chamber‐specific TCs identified in atrial and ventricular fibroblast culture using immunocytochemistry and studied their electrophysiological property by whole‐cell patch clamp. Atrial and ventricular TCs with extended telopodes and alternating podoms and podomers that expressed CD34, c‐Kit and PDGFR‐β were identified. These cells expressed large conductance Ca2+‐activated K+ current (BKCa) and inwardly rectifying K+ current (IKir), but not transient outward K+ current (Ito) and ATP‐sensitive potassium current (KATP). The active channels were functionally competent with demonstrated modulatory response to H2S and transforming growth factor (TGF)‐β1 whereby H2S significantly inhibited the stimulatory effect of TGF‐β1 on current density of both BKCa and IKir. Furthermore, H2S attenuated TGF‐β1‐stimulated KCa1.1/Kv1.1 (encode BKCa) and Kir2.1 (encode IKir) expression in TCs. Our results show that functionally competent K+ channels are present in human atrial and ventricular TCs and their modulation may have significant implications in myocardial physiopathology. 相似文献
994.
Plasmon‐Enhanced Polymer Photovoltaic Device Performance Using Different Patterned Ag/PVP Electrospun Nanofibers
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Significant enhancement of P3HT (poly(3‐hexylthiophene)):PC61BM ([6,6]‐phenyl C61‐butyric acid methyl ester) photovoltaic devices using different patterns of electrospun Ag/PVP composite nanofibers, including nonwoven, aligned, and crossed patterns, is reported. The composite electrospun nanofibers are prepared using in situ reduction of silver (Ag) nanoparticles in Ag/poly(vinyl pyrrolidone) (PVP) via a two‐fluid coaxial electrospinning technique. The composition, crystalline orientation, and particle size of Ag are manipulated by controlling the core/shell solution concentration. The smallest diameter of the composite nanofibers leads to the highest orientation of the Ag nanoparticles and results in the largest conductivity due to geometric confinement. Such composite nanofibers exhibit the surface plasmon resonance (SPR) effect, which provides near field enhancement of electromagnetic field around active layer. Additionally, composite nanofibers with the crossed or nonwoven patterns further enhance high carrier mobility, compared to that of the aligned pattern. It leads to the 18.7% enhancement of the power conversion efficiency of photovoltaic cell compared to the parent device. The results indicate that the high conductivity and SPR effect of the Ag/PVP electrospun nanofibers can significantly improve the photocurrent and PCE, leading to promising organic solar cell applications. 相似文献
995.
Limited prospective data are available on the importance of estimated glomerular filtration rate (GFR) and proteinuria in the prediction of all-cause mortality (ACM) in community-based elderly populations. We examined the relationship between GFR or proteinuria and ACM in 949 randomly selected community-dwelling elderly subjects (aged ≥65 years) over a 5-year period. A spot urine sample was used to measure proteinuria by the dipstick test, and GFR was estimated using the chronic kidney disease-epidemiology collaboration (CKD-EPI) equation. Information about mortality and causes of death was collected by direct enquiry with the subjects and from the national mortality data. Compared to subjects without proteinuria, those with proteinuria of grade ≥1+ had a 1.725-fold (1.134–2.625) higher risk of ACM. Compared to subjects with GFR ≥90 ml/min/1.73 m2, those with GFR<45 ml/min/1.73 m2 had a 2.357 -fold (1.170–4.750) higher risk for ACM. Among the 403 subjects included in the analysis of renal progression, the annual rate of GFR change during follow-up period was −0.52±2.35 ml/min/1.73 m2/year. The renal progression rate was 7.315-fold (1.841–29.071) higher in subjects with GFR<60 ml/min/1.73 m2 than in those with GFR ≥60 ml/min/1.73 m2. Among a community-dwelling elderly Korean population, decreased GFR of <45 ml/min/1.73 m2 and proteinuria were independent risk factors for ACM. 相似文献
996.
Vincent Raoult Michael I. Grant Ana Paula Barbosa Martins Leonardo Manir Feitosa Matias Braccini Diego Cardeosa John Carlson Andrew Chin Tobey Curtis Luís Fernando Carvalho Costa Luís Fernando Rodrigues Filho Tommaso Giarrizzo Jorge Luiz S. Nunes Joo Brullio L. Sales Jane E. Williamson Colin A. Simpfendorfer 《Biology letters》2021,17(7)
997.
Sook Wah Chan Hamed Mirhosseini Farah Saleena Taip Tau Chuan Ling Chin Ping Tan 《Food biophysics》2013,8(4):273-281
Co-enzyme Q10 (CoQ10), a lipophilic compound that widely used in the food and pharmaceutical products was formulated in a κ-carrageenan coated oil-in-water (O/W) emulsion. In this work, we examined the solubility of CoQ10 in different carrier oils and effects of emulsifier type on the formation and stability of CoQ10-loaded O/W emulsion. Nine vegetable oils and four types of emulsifiers were used. CoQ10 was found significantly (p?<?0.05) more soluble in medium chain oils (coconut oil and palm kernel oil) as compared to other vegetable oils. The O/W emulsions were then prepared with 10 % (w/w) coconut oil and palm kernel oil containing 200 g CoQ10/L oil stabilized by 1 % (w/v) emulsifiers (sucrose laurate (SEL), sodium stearoyl lactate (SSL), polyglycerol ester (PE), or Tween 80 (Tw 80)) in 1 % (w/v) κ-carrageenan aqueous solution. Particle size distribution and physical stability of the emulsions were monitored. The droplet sizes (surface weighted mean diameter, D[3,2]) of fresh O/W emulsion in the range of 2.79 to 5.83 μm were observed. Irrespective of the oil used, results indicated that complexes of SSL/κ-carrageenan provided the most stable CoQ10-loaded O/W emulsion with smaller and narrower particle size distribution. Both macroscopic and microscopic observations showed that O/W emulsion stabilized by SSL/κ-carrageenan is the only emulsion that exhibited no sign of coalescence, flocculation, and phase separation throughout the storage period observed. 相似文献
998.
Wan Wui Jong Pei Jean Tan Fadzly Adzhar Kamarulzaman Michele Mejin Diana Lim Ida Ang Margarita Naming Tiong Chia Yeo Anthony Siong Hock Ho Soo Hwang Teo Hong Boon Lee 《化学与生物多样性》2013,10(8):1475-1486
Photodynamic therapy (PDT) is a medical treatment that involves the irradiation of an administered photosensitizing drug with light of a particular wavelength to activate the photosensitizer to kill abnormal cells. To date, only a small number of photosensitizers have been clinically approved for PDT, and researchers continue to look for new molecules that have more desirable properties for clinical applications. Natural products have long been important sources of pharmaceuticals, and there is a great potential for discovery of novel chemotypes from under‐explored biodiversities in the world. The objective of this study is to mine the terrestrial plants in Sarawak, Borneo Island, for new photosensitizers for PDT. In a screening program from 2004 to 2008, we prepared and studied 2,400 extracts from 888 plants for their photosensitizing activities. This report details the bioprospecting process, preparation and testing of extracts, analysis of the active samples, fractionation of four samples, and isolation and characterization of photosensitizers. 相似文献
999.
1000.
A deletion mutant of the nucleocapsid protein (NPΔc375) of Newcastle disease virus self-assembles into a long helical structure when expressed in Escherichia coli. However, the NPΔc375 subjects to proteolytic activity of host cell endogenous proteases during the protein recovery process. Image analysis of Western blots using the Quantity One software was performed to identify the size of the degraded bands and hence the potential proteases cleavage sites were predicted. The data obtained from this image analysis were compared to those identified with the PeptideCutter program; the potential proteases that degrade the NPΔc375 were identified to be mainly the metallo and serine proteases. Combination of ethylenediaminetetraacetic acid and phenylmethylsulfonyl fluoride at their optimal concentration gave a synergistic effect and increased the NPΔc375 yield by 2.1-fold. The antigenicity and self-assembled long helical structure long helical structure of NPΔc375 were preserved after treatment with the protease inhibitors. 相似文献