Comprehensive mutational analysis of primary and relapse acute promyelocytic leukemia

Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17), leading to the formation of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations, which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, whereas mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large-scale activation of gene expression and reduced in vitro differentiation potential.

Measurements of Elliptic and Triangular Flow in High-Multiplicity 3He+Au Collisions at √(s(NN))=200 GeV

We present the first measurement of elliptic (v(2)) and triangular (v(3)) flow in high-multiplicity (3)He+Au collisions at √(s(NN))=200  GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in (3)He+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the (3)He+Au system. The collective behavior is quantified in terms of elliptic v(2) and triangular v(3) anisotropy coefficients measured with respect to their corresponding event planes. The v(2) values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with various theoretical predictions are made, including to models where the hot spots created by the impact of the three (3)He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.

The ASACUSA Micromegas Tracker: A cylindrical, bulk Micromegas detector for antimatter research

The ASACUSA Micromegas Tracker (AMT; ASACUSA: Atomic Spectroscopy and Collisions Using Slow Antiprotons) was designed to be able to reconstruct antiproton-nucleon annihilation vertices in three dimensions. The goal of this device is to study antihydrogen formation processes in the ASACUSA cusp trap, which was designed to synthesise a spin-polarised antihydrogen beam for precise tests of Charge, Parity, and Time (CPT) symmetry invariance. This paper discusses the structure and technical details of an AMT detector built into such an environment, its data acquisition system and the first performance with cosmic rays.

Increased undercarboxylated osteocalcin/intact osteocalcin ratio in patients undergoing hemodialysis

Serum undercarboxylated osteocalcin (ucOC)/intact osteocalcin (iOC) ratio increased >1.0 in the patients undergoing hemodialysis, particularly in those with high bone turnover state. Consequently, serum ucOC/iOC ratio might lose its significance as a bone metabolic marker to indicate vitamin K deficiency in hemodialysis patients.

INTRODUCTION

Serum intact osteocalcin (iOC), undercarboxylated OC (ucOC), and the ucOC/iOC ratio are considered clinically relevant indices in pre-dialysis chronic kidney disease (CKD) and hemodialysis (HD) patients, despite their accumulation in uremic serum.

METHODS

Serum iOC and ucOC were measured along with serum intact parathyroid hormone (iPTH), bone alkaline phosphatase (BAP), and tartrate-resistant acid phosphatase (TRACP)-5b in 89 pre-dialysis CKD and 189 HD patients.

RESULTS

Serum iOC and ucOC showed significantly negative correlations with estimated glomerular filtration rate in pre-dialysis CKD patients, although serum ucOC/iOC ratio did not correlate. Serum ucOC was significantly greater in HD patients than in pre-dialysis CKD patients, while serum iOC did not differ significantly, resulting in serum ucOC/iOC ratio >1.0 in 135 (71.4%) out of 189 HD patients. HD patients with high serum ucOC/iOC ratio (>1.0) had a significantly younger age and significantly higher values of body mass index, serum creatinine, albumin, phosphate, iPTH, and TRACP-5b than those with low ucOC/iOC ratio (≤ 1.0). The baseline iPTH and P1NP correlated with the changes of the ucOC/iOC ratio during the 2 days of the inter-dialytic period. Multivariate analysis showed that log [ucOC/iOC] in HD patients was significantly associated with log [iPTH], log [BAP], or log [TRACP-5b].

CONCLUSIONS

Serum ucOC/iOC ratio >1.0 was observed in as high as 71.4% of HD patients, preferentially with high bone turnover state, in comparison with pre-dialysis CKD patients. These data suggested that serum ucOC/iOC ratio might lose its significance as a bone metabolic marker to indicate vitamin K deficiency in HD patients.

Decreased cortical thickness, as estimated by a newly developed ultrasound device, as a risk for vertebral fracture in type 2 diabetes mellitus patients with eGFR of less than 60 mL/min/1.73 m2

Cortical porosity is increasingly recognized as an important risk for fracture in DM patients. The present study demonstrated that decreased cortical thickness, assessed using a newly developed quantitative ultrasonic bone densitometry, is a significant risk factor for vertebral fractures in type 2 diabetes mellitus patients with stage 3 or higher chronic kidney disease, but not in those without.

INTRODUCTION

Cortical porosity is increasingly recognized as an important risk factor for fracture in type 2 diabetes mellitus (T2DM) patients as well as in stage 3 chronic kidney disease (CKD) patients in whom serum parathyroid hormone (PTH) starts to increase. The present study aimed to clarify whether the coexistence of CKD might affect the relationship of decreased cortical thickness (CoTh) in the development of vertebral fractures (VF) in T2DM patients.

METHODS

In this cross-sectional study, trabecular bone mineral density (TrBMD), elastic modulus of trabecular bone (EMTb), and CoTh were estimated with a new quantitative ultrasound bone densitometry in 173 T2DM patients. VFs were identified radiographically.

RESULTS

Thirty-nine patients (22.5%) had VF. Those with estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) (low eGFR) showed a significantly higher VF rate (32.4%) than those with eGFR ≥60 mL/min/1.73 m(2) (high eGFR, 16.2%). Serum PTH was significantly higher with low eGFR than with high eGFR. In those with high eGFR, EMTb was significantly lower in VF(+) than VF(-). In those with low eGFR, TrBMD, EMTb, and CoTh were significantly lower in VF(+) than in VF(-). In a multivariate logistic regression analysis, EMTb was independently and significantly associated with VF in T2DM patients with a high eGFR, in contrast to those with only CoTh with VF in T2DM with low eGFR.

CONCLUSION

This study demonstrated CoTh as a factor independently associated with VF in T2DM patients with low eGFR and increasing serum PTH levels.

Serial magnetic resonance imaging study of posterior cruciate ligament reconstruction or augmentation using hamstring tendons

PURPOSE

The purpose of this study was to analyze serial changes in the magnetic resonance imaging (MRI) signals of autograft hamstrings single bundle posterior cruciate ligament (PCL) reconstruction and the effects of remnant preservation (augmentation).

MATERIAL AND METHODS

Twenty-two isolated PCL injuries were arthroscopically reconstructed or augmented with hamstring tendons. MRI scans were obtained at 3, 6, and 12 months, and prior to the second-look arthroscopy (average 20.7 months). The patients were divided into 2 groups by remnant preservation: five PCL reconstructions after PCL remnant resection (Group Rec) (23%), and 17 reconstructions preserving the remnant (Group Aug) (77%). The 22 patients were also divided in two groups depending on the location of the PCL tear. There were 9 knees with proximal tear (Type P) (41%) and 13 knees with distal tear (Type D) (59%). The signal intensity and fiber continuity of 4 zones (proximal, middle, distal intra-articular and tibial tunnel zones) were evaluated by the Mariani score.

RESULTS

The average MRI evaluation score gradually increased from 6 months through the final MRI. The intra-articular part of the graft exhibited slower maturation (12 months - final scan) as compared with the tibial tunnel (6-12 months). The distal zone underwent better maturation than the proximal or middle zones at all points. In the proximal zone, the score for Group Aug was significantly higher than Group Rec. In the proximal zone, the Type D score with a proximally-preserved remnant was significantly higher than Type P without a proximal remnant.

CONCLUSIONS

The hamstring tendons require more than 1 year to achieve low-signal intensity. PCL remnant has a beneficial effect on the maturation of the hamstring graft.

LEVEL OF EVIDENCE IV

therapeutic case series.