Molecular characterization of Citrus tristeza virus isolates from Pakistan based on CPG/Hinf I restriction fragment length polymorphism (RFLP) groups analysis

From six different districts of Punjab, Pakistan, 85 isolates of Citrus tristeza virus (CTV) were collected and characterized based on coat protein gene (CPG) analysis. All isolates were collected from field trees showing various CTV symptoms such as decline in most citrus varieties, inverse pitting on some sour orange rootstocks below bud union, mild-to-moderate stem-pitting on the trunk of some sweet orange. The CTV CP gene of all isolates was amplified by reverse transcriptase polymerase chain reaction (RT–PCR) using CP gene-specific primers yielding 672 bp. The maximum disease incidence was found in sweet orange followed by mandarin and grapefruit. These isolates were then subjected to CPG/Hinf I restriction fragment length polymorphism (RFLP) analysis. Mixed infection of CTV isolates was found very common in the field tress in Pakistan. The most dominant CPG/Hinf I RFLP groups III, I and VI are the basic causal epidemic in Pakistan. Moreover, based on symptoms in the field trees, CPG/Hinf I RFLP groups III, I and VI are considered to be the obvious causes of decline and stem-pitting in Pakistan.Key words: Citrus tristeza virus, CPG/Hinf I restriction fragment length polymorphism (RFLP) groups, decline, stem-pitting

Liner Exchange Into A Well Fixed Acetabular Shell In Revision Total Hip Arthroplasty

OBJECTIVE To investigate clinical outcomes and complications of isolated polyethylene liner exchange for revision total hip arthroplasty. METHODS From April 1 995 to December 2007, 80 patients (93 hips) underwent revision total hip arthroplasty during which only polyethylene liner was exchanged with reservation of acetabular cup. There were 41 males and 39 females, aged from 27 to 82 years (average, 53.3 years). The duration from the primary THA to the revision surgery ranged from 0.3 to 18.4 years (average, 10.9 years). The reasons for liner exchange included: polyethylene wear with osteolysis (78 hips), polyethylene wear without osteolysis (5 hips), polyethylene wear with stem loosening (4 hips), recurrent dislocation (3 hips), infection (1 hip), periprosthetic fracture (1 hip) and liner dislodgement (1 hip). Forty-seven liners were fixed into the old cup using cement, and 46 were fixed with the original locking mechanism. Sixty cross-linked polyethylene liners and 33 conventional polyethylene liners were used. RESULTS All patients were followed up for 5 to 15 years (average, 7 years). The average Harris hip score improved from preoperative 86.0±16.9 to 89.4±11.6 at final follow-up. Complications included dislocation (10 hips), infection (2 hips), periprosthetic fracture (1 hip) and liner dislodgement (1 hip). Ten hips underwent rerevision due to different reasons: cup exchange (5 hips), conventional polyethylene wear (2 hips), infection (2 hips) and liner dislodgement (1 hip). Using component loosening as the end point, the 10-year survival rate was 100% in the cement fixation group and 84.8% in the original locking group. Using rerevision as the end point, the 10-year survival rate was 90.4% in the cement fixation group and 65.0% in the original locking group. CONCLUSION Liner exchange either with cement or original locking mechanism is a safe and successful method. Highly cross-linked polyethylene has a higher wear resistance, which can reduce incidence of osteolysis and improve survival rate of prosthesis.目的探討保留髖臼杯更換聚乙烯襯墊在全髖關節翻修術中的作用.方法1995年4月至2007年12月,80例(93髖)接受保留髖臼杯更換聚乙烯襯墊手術.男41例,女39例;年齡2782歲,平均53.3歲.初次置換與更換襯墊手術間隔0.318.4年,平均10.9年.翻修原因:聚乙烯磨損及骨溶解78髖,聚乙烯接近完全磨損但無骨溶解5髖,聚乙烯磨損及股骨柄假體鬆動4髖,復發性關節脫位3髖,感染1髖,假體周圍骨折1髖,襯墊脫位1髖.翻修襯墊採用高交聯聚乙烯60髖、普通聚乙烯33髖,以骨水泥固定47髖、原鎖定機制固定46髖.結果隨訪515年,平均7年.術前Harris髖關節評分(86.0±16.9)分,終末隨訪時(89.4±11.6)分.並發症包括脫位10髖,感染2髖,假體周圍骨折1髖,襯墊脫落1髖.10髖再次翻修:髖臼杯翻修5髖,普通聚乙烯磨損2髖,感染2髖,襯墊脫落1髖.普通聚乙烯組新發骨溶解12髖.以假體鬆動為終點,十年生存率骨水泥固定組100%、原鎖定機制固定組84.8 %;以再次翻修為終點,十年生存率分別為90.4%和65.0%.結論以骨水泥或原鎖定機制固定翻修襯墊均安全有效.高交聯聚乙烯耐磨性較好,能降低骨溶解風險,假體存活率更高

Proteome profiling of cadmium-induced apoptosis by antibody array analyses in human bronchial epithelial cells

Protein array technology is a powerful platform for the simultaneous determination of the expression levels of a number of proteins as well as post-translational modifications such as phosphorylation. Here, we screen and report for the first time, the dominant signaling cascades and apoptotic mediators during the course of cadmium (Cd)-induced cytotoxicity in human bronchial epithelial cells (BEAS-2B) by antibody array analyses. Proteins from control and Cd-treated cells were captured on Proteome Profiler™ Arrays for the parallel determination of the relative levels of protein phosphorylation and proteins associated with apoptosis. Our results indicated that the p38 MAPK- and JNK-related signal transduction pathways were dramatically activated by Cd treatment. Cd potently stimulates the phosphorylations of p38α (MAPK14), JNK1/2 (MAPK8/9), and JUN; while the phosphorylations of Akt1, ERK1/2 (MAPK3/1), GSK3β, and mTOR were suppressed. Moreover, there was an induction of proapoptotic protein BAX, release of cytochrome c (CYCS) from mitochondria, activation of caspase-3/9 (CASP3/9); as well as decreased expression of cell cycle checkpoint proteins (TP53, p21, and p27) and several inhibitors of apoptosis proteins (IAPs) [including cIAP-1/2 (BIRC2/3), XIAP (BIRC4), and survivin (BIRC5)]. Pretreatment of cells with the thiol antioxidant glutathione or p38 MAPK/JNK inhibitors before Cd treatment effectively abrogated ROS activation of p38 MAPK/JNK pathways and apoptosis-related proteins. Taken together, our results demonstrate that Cd causes oxidative stress-induced apoptosis; and the p38 MAPK/JNK and mitochondrial pathways are more importantly participated for signal transduction and the induction of apoptosis in Cd-exposed human lung cells.published_or_final_versio

Spherical montmorillonite-supported nano-silver as a self-sedimentary catalyst for methylene blue removal

Supported metal nanoparticles using various substrates have been proven as a highly efficient approach for solving the problems of aggregation and recyclability of metal nanoparticles. However, the reusability procedure often involved the abundant devices, which obviously increased the cost and heavily limited the large-scale application of metal nanoparticles. In this work, spherical montmorillonite was used firstly as the substrate for supporting silver nanoparticles on its surface through polydopamine chemistry method. The loading of silver nanoparticles with 40 nm in diameter was 15.2 wt% and the specific surface area of this prepared spherical montmorillonite supported silver nanoparticles catalyst was 45.3 m(2)/g, giving the catalyst an optimized apparent reduction rate constant k of 1.22 min(-1) for the reduction of methylene blue. Furthermore, the prepared catalyst with quickly self-sedimentary property in aqueous solution were conveniently recovered and reused without any devices involves. The spherical morphology and catalytic performance of prepared catalyst were almost unaltered after 5 cycles. Our research aims at opening a new avenue to easily realize the reusability of silver nanoparticles through using the substrate with the self-sedimentary property

EM23, a natural sesquiterpene lactone, targets thioredoxin reductase to activate JNK and cell death pathways in human cervical cancer cells

Sesquiterpene lactones (SLs) are the active constituents of a variety of medicinal plants and found to have potential anticancer activities. However, the intracellular molecular targets of SLs and the underlying molecular mechanisms have not been well elucidated. In this study, we observed that EM23, a natural SL, exhibited anti-cancer activity in human cervical cancer cell lines by inducing apoptosis as indicated by caspase 3 activation, XIAP downregulation and mitochondrial dysfunction. Mechanistic studies indicated that EM23-induced apoptosis was mediated by reactive oxygen species (ROS) and the knockdown of thioredoxin (Trx) or thioredoxin reductase (TrxR) resulted in a reduction in apoptosis. EM23 attenuated TrxR activity by alkylation of C-terminal redox-active site Sec498 of TrxR and inhibited the expression levels of Trx/TrxR to facilitate ROS accumulation. Furthermore, inhibition of Trx/TrxR system resulted in the dissociation of ASK1 from Trx and the downstream activation of JNK. Pretreatment with ASK1/JNK inhibitors partially rescued cells from EM23-induced apoptosis. Additionally, EM23 inhibited Akt/mTOR pathway and induced autophagy, which was observed to be proapoptotic and mediated by ROS. Together, these results reveal a potential molecular mechanism for the apoptotic induction observed with SL compound EM23, and emphasize its putative role as a therapeutic agent for human cervical cancer.published_or_final_versio

Nuclear receptors in vascular biology

Nuclear receptors sense a wide range of steroids and hormones (estrogens, progesterone, androgens, glucocorticoid, and mineralocorticoid), vitamins (A and D), lipid metabolites, carbohydrates, and xenobiotics. In response to these diverse but critically important mediators, nuclear receptors regulate the homeostatic control of lipids, carbohydrate, cholesterol, and xenobiotic drug metabolism, inflammation, cell differentiation and development, including vascular development. The nuclear receptor family is one of the most important groups of signaling molecules in the body and as such represent some of the most important established and emerging clinical and therapeutic targets. This review will highlight some of the recent trends in nuclear receptor biology related to vascular biology

Control of magnetic anisotropy by orbital hybridization in (La0.67Sr0.33MnO3)n/(SrTiO3)n superlattice

The asymmetry of chemical nature at the hetero-structural interface offers an unique opportunity to design desirable electronic structure by controlling charge transfer and orbital hybridization across the interface. However, the control of hetero-interface remains a daunting task. Here, we report the modulation of interfacial coupling of (La0.67Sr0.33MnO3)n/(SrTiO3)n superlattices by manipulating the periodic thickness with n unit cells of SrTiO3 and n unit cells La0.67Sr0.33MnO3. The easy axis of magnetic anisotropy rotates from in-plane (n = 10) to out-of-plane (n = 2) orientation at 150 K. Transmission electron microscopy reveals enlarged tetragonal ratio > 1 with breaking of volume conservation around the (La0.67Sr0.33MnO3)n/(SrTiO3)n interface, and electronic charge transfer from Mn to Ti 3d orbitals across the interface. Orbital hybridization accompanying the charge transfer results in preferred occupancy of 3d3z2-r2 orbital at the interface, which induces a stronger electronic hopping integral along the out-of-plane direction and corresponding out-of-plane magnetic easy axis for n = 2. We demonstrate that interfacial orbital hybridization in superlattices of strongly correlated oxides may be a promising approach to tailor electronic and magnetic properties in device applications