Search

Background Circular RNAs (circRNAs) are possible biomarkers for many diseases, but the knowledge of circRNAs in the peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE) remains limited. This study aimed to assess the expression of circRNAs in PBMCs from patients with SLE and healthy individuals by RNA sequencing (RNA-seq). Methods In total, 128 circRNAs were significantly differentially expressed including 39 upregulated and 89 downregulated circRNAs in four new-onset SLE patients compared with three healthy controls. After verification of the four candidate circRNAs in 49 patients with SLE and 37 controls using quantitative real-time polymerase chain reaction (qRT-PCR) assays, a previously undescribed circRNA with potential translation activity, circPTPN22, was selected to confirm its clinical significance. Results Bioinformatics analysis demonstrated that the parent gene of circPTPN22 was protein tyrosine phosphatase non-receptor type 22 (PTPN22), a potent regulator of T cell activation. The downregulation of circPTPN22 in patients with SLE was strongly negatively correlated with their Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores. circRNA-miRNA-mRNA co-expression network analysis indicated a correlation between circPTPN22 and the miRNAs and mRNAs related to immunological regulation including the development of SLE. Patients with higher SLEDAI scores had lower circPTPN22 expression levels, and long-term hormone treatment significantly increased circPTPN22 levels. Receiver operating characteristic curve analysis indicated that circPTPN22 has good diagnostic value for SLE. Conclusion Our data demonstrated the aberrant expression of circRNAs in patients with SLE compared with healthy controls; circPTPN22 might function as a diagnostic and disease severity indicator in SLE. [ABSTRACT FROM AUTHOR]

Previous studies suggest that ropivacaine causes the least neurotoxicity among local anaesthetics. Most data derive from a single injection of ropivacaine into the subarachnoid space. The histological changes and behavioural effects of repeated intrathecal administration have yet to be studied. We examined the possible neurotoxicity of multiple doses of intrathecal ropivacaine in rats. Rats received 0.12 ml/kg body weight ropivacaine in normal saline at concentrations of 0.25%, 0.5%, 0.75% and 1.0% at 90-minute intervals via an implanted intrathecal catheter (ID 0.12 mm, OD 0.35 mm) for 48 hours. At L3, the spinal cord and posterior roots were examined by light and electron microscopy. We performed in situ TUNEL assay to evaluate apoptosis in the spinal cord. Sensory threshold to noxious stimulation along with behavioural change were also studied. Both 0.75% and 1.0% ropivacaine induced neuronal injury characterised by infiltration of inflammatory cells, vacuolation of myelin sheaths and axons, abnormal morphology of neurons and apoptosis in the spinal cord, mainly in posterior roots and the adjacent posterior white matter Compared to controls, the percentage of maximum possible effect did not show any significant differences between the rats treated with variable concentrations of ropivacaine or tested with either heat or mechanical stimulation. As expected, the recovery time to normal ambulation was prolonged as the ropivacaine concentration was increased. Ropivacaine can induce neurotoxicity and trigger apoptosis in a dose-dependent manner after repeated intrathecal administration. Although the clinical safety profile of ropivacaine appears favourable compared with other local anaesthetics, it is possible our findings have clinical significance. [ABSTRACT FROM AUTHOR]

The article focuses on a study which investigated the possible neurotoxicity of multiple doses of intrathecal ropivacaine in rats. Study authors injected ropivacaine in the rats via an implanted intrathecal catheter at 90-minute intervals. They evaluated apoptosis in the spinal cord using in situ TUNEL assay. They concluded that ropivacaine can induce neurotoxicity and apoptosis in a dose-dependent manner.

Aluminium is a very important material used in the semiconductor industry as an interconnection layer. The most popular method of depositing aluminium films is the physical vapour deposition (PVD) process. The objective of the present study is to improve aluminium film uniformity by optimising the process conditions to use a thicker target and meet the demand for more uniform films on wafer surfaces. Aluminium films were deposited by a sputtering process on 200 mm wafers in PVD chambers. Experiments were carried out to find the process factors that affect film uniformity. The results revealed that film uniformity was affected significantly by wafer to target spacing and process pressure. Film characterisation was then performed by measuring grain size and film surface roughness, and performing package level electron migration, ball shear and bond pull tests. A higher process pressure resulted in more uniform films with bigger grains, lower surface roughness, longer reliability lives and higher ball shear values. With optimised process conditions, the aluminium layer uniformity can be maintained at <1·5% throughout the whole target life (∼1000 kWh). [ABSTRACT FROM AUTHOR]

A carbon void on a hard disk surface is a defect that occurs during the carbon sputter deposition process for the manufacture of hard disks. Because the carbon overcoat on hard disk surfaces acts as a barrier to corrosion, it is essential to reduce the number and size of carbon void defects. In the present study, carbon void defects on hard disk surfaces were studied using various failure analysis tools. The influence of the substrate bias voltage on the number and size of carbon void defects was also investigated. The results of the failure analysis show that there was a 40–50% loss in recorded magnetic bit signal due to an increase in the gap between a recording head and a hard disk surface with carbon void defects. Removing the bias voltage on the substrate during the sputtering process reduced the carbon void defects significantly. The average number of carbon void defects per disk surface was reduced from 4 to 0.5. In addition, the average size of the carbon void defect was reduced from 8 μm to 3.8 μm. [ABSTRACT FROM AUTHOR]

Systemic lupus erythematosus (SLE) has protean clinical manifestations of varying severity over the course of its onset, exacerbation, remission and flare that could often pose significant challenges for clinicians in their decision making as to whether to treat aggressively or to look for concurrent conditions such as infection with opportunistic pathogens. Human cytomegalovirus (HCMV) is one of those pathogens and is frequently encountered in our daily management of lupus patients. To investigate the clinical characteristics and therapeutic options of active HCMV infection in patients with SLE, we retrospectively reviewed clinical data of 105 inpatients in our department of Rheumatology and Clinical Immunology of Peking Union Medical College Hospital (PUMCH) diagnosed with both SLE and active HCMV infection from January 2006 to January 2012. Three groups were designated that included 42 cases of HCMV triggering SLE, 31 cases of HCMV exacerbating SLE, and 32 cases of HCMV mimicking SLE flare based on the relationship of HCMV infection and SLE. 1) Hematocytopenia (81%), fever (73.3%) and liver dysfunction (54.3%) were the most common clinical manifestations. The differences among the three groups with regard to butterfly erythema, cutaneous vasculitis, arthritis, serositis, central nervous system involvement and renal involvement were statistically significant (p < 0.05). 2) Positive rate of HCMV-pp65, compared with HCMV-IgM and HCMV-DNA, was the highest (84.9%) in patients with SLE and active HCMV infection. 3) Following 14–21 days of inductive treatment with ganciclovir, a total of 26 out of 56 patients were still positive with HCMV-IgM (nine of 19, 47.6%) and pp65 (17/37, 45.9%). Among them, seven cases suffered HCMV relapses in three months with six cases of sustained HCMV-pp65 antigenemia. In conclusion, hematocytopenia, fever and liver dysfunction should remind us to consider HCMV infection. Butterfly erythema, cutaneous vasculitis, arthritis, serositis, central nervous system involvement and renal lesion were relatively characteristic symptoms of lupus activity. HCMV-pp65 is a sensitive indicator to guide antiviral therapy. Induction therapy using ganciclovir with a duration of 14∼21 days is not sufficient, and continued HCMV-pp65 positivity may require prolonged antiviral treatment in lupus patients. [ABSTRACT FROM AUTHOR]