Ion optics of RHIC electron beam ion source

RHIC electron beam ion source has been commissioned to operate as a versatile ion source on RHIC injection facility supplying ion species from He to Au for Booster. Except for light gaseous elements RHIC EBIS employs ion injection from several external primary ion sources. With electrostatic optics fast switching from one ion species to another can be done on a pulse to pulse mode. The design of an ion optical structure and the results of simulations for different ion species are presented. In the choice of optical elements special attention was paid to spherical aberrations for high-current space charge dominated ion beams. The combination of a gridded lens and a magnet lens in LEBT provides flexibility of optical control for a wide range of ion species to satisfy acceptance parameters of RFQ. The results of ion transmission measurements are presented.

Abnormal epigenetic modifications in peripheral blood mononuclear cells from patients with alopecia areata

BACKGROUND

Alopecia areata (AA) is a hair loss disease caused by T-cell-mediated autoimmune reactions against anagen-stage hair follicles. Although the exact aetiology is poorly understood, there is evidence to suggest that both genetic and environmental factors are involved in AA pathogenesis.

OBJECTIVES

To analyse DNA methylation and histone modification patterns in peripheral blood mononuclear cells (PBMCs) of patients with AA.

METHODS

PBMC samples were obtained from 25 patients with AA and 20 healthy controls. Global DNA methylcytosine levels, as well as histone acetylation and methylation levels, were measured by enzyme-linked immunosorbent assay. mRNA expression levels were determined using real-time quantitative reverse transcription-polymerase chain reaction.

RESULTS

Genomic DNA methylation in PBMCs of patients with AA was increased relative to controls. DNMT1, MBD1 and MBD4 expression levels were significantly higher in AA PBMCs than in controls, and DNMT1 transcription levels positively correlated with global DNA methylation levels in patient samples. Histone H3 acetylation was significantly increased and histone H3 lysine 4 methylation was significantly decreased in patient PBMCs compared with healthy controls. Histone H3 acetylation levels were positively correlated with AA disease severity, and with RANTES (CCL5) mRNA expression in PBMCs of patients with AA. These changes were accompanied by increased p300 (EP300), histone deacetylase 1 (HDAC1), myeloid/lymphoid or mixed lineage leukemia (MLL), SET7/9 (SETD7), G9A (EHMT2), JMJD2C (KDM4C) and JARID1A (KDM5A) expression, as well as reduced HDAC2, HDAC7, LSD1 (KDM1A), JMJD2A (KDM4A) and JMJD2B (KDM4B) expression.

CONCLUSIONS

DNA methylation and histone modification status are altered in PBMCs of patients with AA, possibly due to the deregulation of epigenetic regulatory genes. These changes may contribute to the activation of pathological immune responses in AA.

Mechanism and genotype-phenotype correlation of two proximal 6q deletions characterized using mBAND, FISH, array CGH, and DNA sequencing

Proximal 6q deletions have a milder phenotype than middle and distal 6q deletions. We describe 2 patients with non-overlapping deletions of about 15 and 19 Mb, respectively, which subdivide the proximal 6q region into 2 parts. The aberrations were identified using karyotyping and analysed using mBAND and array CGH. The unaffected mother of the first patient carried a mosaic karyotype with the deletion in all metaphases analysed and a small supernumerary marker formed by the deleted material in about 77% of cells. Her chromosome 6 centromeric signal was split between the deleted chromosome and the marker, suggesting that this deletion arose through the centromere fission mechanism. In this family the location of the proximal breakpoint in the centromere prevented cloning of the deletion junction, but the junction of the more distal deletion in the second patient was cloned and sequenced. This analysis showed that the latter aberration was most likely caused by non-homologous end joining. The second patient also had a remarkably more severe phenotype which could indicate a partial overlap of his deletion with the middle 6q interval. The phenotypes of both patients could be partly correlated with the gene content of their deletions and with phenotypes of other published patients.

Acute kidney injury in Chinese patients with lupus nephritis: a large cohort study from a single center

OBJECTIVE

In this study we assess clinicopathologic characteristics, treatment and prognosis of acute kidney injury (AKI) in a large cohort of Chinese patients with lupus nephritis.

METHODS

The clinical, laboratory, renal histopathology, treatment and outcome data were retrospectively collected and compared between lupus nephritis patients with and without AKI. The impact of AKI on renal outcome was evaluated.

RESULTS

Among 322 patients with renal biopsy-proven lupus nephritis, 66 (20.5%) were identified as AKI. Male predominance was observed in patients with AKI (p < 0.001). In comparison with the non-AKI group, patients with AKI had significantly higher proportions of serositis (p < 0.001), neurologic disorder (p = 0.026), anemia (p < 0.001), thrombocytopenia (p = 0.013) and nephrotic syndrome (p = 0.011), but significant lower serum C3 (p < 0.001). The Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores, renal pathological activity indices and chronicity indices were significantly higher in the AKI group (p < 0.001 in all cases). Regarding outcome, the AKI group had a significantly poorer renal outcome compared with non-AKI group (p < 0.001). In the AKI group, patients with crescentic glomerulonephritis and thrombotic microangiopathy had the worst renal outcome. AKI was an independent risk factor for renal outcome (hazard ratio [HR] = 5.819, 95% confidence interval 2.411-14.044, p < 0.001).

CONCLUSIONS

AKI is common in lupus nephritis and is an independent risk factor for renal outcome.

Nerve growth factor augments neuronal responsiveness to noradrenaline in cultured dorsal root ganglion neurons of rats

Increasing evidence indicates that both the nerve growth factor (NGF) and adrenergic systems play a very important role in the development of nociception. However, there is little information concerning the functional interactions between these two systems in the dorsal root ganglion (DRG). The present study tested the hypothesis that NGF could affect neuronal responsiveness to noradrenaline (NA) on the nociceptive DRG neurons, thus enhancing the nociceptive signals. To investigate this issue, spontaneous action potentials were recorded in cultured DRG neurons using current-clamp recording. When NGF (50 ng/ml, 24 h) was administered in the neuronal cultures, the neuronal firing response to NA (10 μM) was augmented in TrkA-positive neurons (3.02±0.28 Hz with NGF treatment vs. 1.36±0.14 Hz in control, P<0.05), indicating that chronic NGF treatment significantly enhanced the neuronal response to NA. Pretreatment of neurons with either the α-adrenergic receptor (AR) antagonist phentolamine (100 μM) or α1-AR antagonist prazosin (50 μM) significantly inhibited the enhanced firings of DRG neurons induced by NA. In addition, treatment of neuronal cultures with NGF (50 ng/ml, 24 h) induced a two-fold increase in α1b-AR expression, as detected with real-time reverse transcription PCR (RT-PCR) and Western blots, but had no effect on α2-AR expression. These observations indicate that NGF augmented neuronal responsiveness to NA in DRG neurons via increasing α1b-AR expression, and this could contribute to the development of pain sensitization.

MICA*002:04: a new allele identified by sequence-based typing in a Chinese individual

The novel MICA*002:04 allele differs from MICA*002:01 by a single mutation at position 486 (C>A) in codon 20 (GCC>GCA) in exon 3.

Late onset lupus nephritis in Chinese patients: classified by the 2003 International Society of Nephrology and Renal Pathology Society system

AIM

The aim of this study was to assess clinicopathological characteristics and outcomes of a cohort of Chinese patients with late onset lupus nephritis.

METHODS

Clinical, pathological and outcome data for patients with late onset lupus nephritis (onset at age ≥50 years) and early onset lupus nephritis (onset at age ≤40 years) were retrospectively analyzed and compared.

RESULTS

Among 271 patients with renal biopsy-proven lupus nephritis, 30 were identified as having late onset lupus nephritis and 241 were identified as having early onset lupus nephritis. Lower female predominance was observed in the late onset patients (p = 0.06). The interval between presentation of lupus nephritis and diagnosis was significantly longer in the late onset group than in the early onset group (p = 0.003). In comparison with early onset group, patients in the late onset group had significantly lower scores for endocapillary hypercellularity (p = 0.041), subendothelial hyaline deposits (p = 0.022) and glomerular leukocyte infiltration (p = 0.032), but had significantly higher scores for tubular atrophy (p = 0.037) and interstitial fibrosis (p = 0.018). Regarding long-term survival and renal outcome, there was no significant difference between the two groups, although it seemed that the early onset group had a poorer renal outcome (p = 0.077, hazard ratio (HR) = 3.909, 95% CI: 0.862-17.726).

CONCLUSIONS

Patients with late onset lupus nephritis were usually diagnosed later; they had milder active lesions and more severe chronic lesions in renal pathology. However, the renal outcome was similar between late and early onset patients.