Experimental Demonstration of Inequivalent Mutually Unbiased Bases.

Quantum measurements based on mutually unbiased bases (MUBs) play crucial roles in foundational studies and quantum information processing. It is known that there exist inequivalent MUBs, but little is known about their operational distinctions, not to say experimental demonstration. In this Letter, by virtue of a simple estimation problem, we experimentally demonstrate the operational distinctions between inequivalent triples of MUBs in dimension 4 based on high-precision photonic systems. The experimental estimation fidelities coincide well with the theoretical predictions with only 0.16% average deviation, which is 25 times less than the difference (4.1%) between the maximum estimation fidelity and the minimum estimation fidelity. Our experiments clearly demonstrate that inequivalent MUBs have different information extraction capabilities and different merits for quantum information processing.

Minimum-Consumption Discrimination of Quantum States via Globally Optimal Adaptive Measurements.

Reducing the average resource consumption is the central quest in discriminating non-orthogonal quantum states for a fixed admissible error rate ϵ. The globally optimal fixed local projective measurement for this task is found to be different from that for previous minimum-error discrimination tasks [S. Slussarenko et al., Phys. Rev. Lett. 118, 030502 (2017)PRLTAO0031-900710.1103/PhysRevLett.118.030502]. To achieve the ultimate minimum average consumption, here we develop a general globally optimal adaptive strategy (GOA) by subtly using the updated posterior probability, which works under any error rate requirements and any one-way measurement restrictions, and can be solved by a convergent iterative relation. First, under the local measurement restrictions, our GOA is solved to serve as the local bound, which saves 16.6 copies (24%) compared with the previously best globally optimal fixed local projective measurement. When the more powerful two-copy collective measurements are allowed, our GOA is experimentally demonstrated to beat the local bound by 3.9 copies (6.0%). By exploiting both adaptivity and collective measurements, our Letter marks an important step toward minimum-consumption quantum state discrimination.

microRNA-630 Regulates Underglycosylated IgA1 Production in the Tonsils by Targeting TLR4 in IgA Nephropathy.

IgA nephropathy (IgAN) is the most common primary glomerular disease. The characteristic pathology involves immune complexes formed by the deposition of IgA1 and underglycosylated IgA1 aggregates in the mesangial area, which may be accompanied by the deposition of IgG and/or IgM and complement components. However, the molecular mechanisms of IgAN remain unclear. In the present study, microarray analysis showed that the expression of microRNA-630 (miR-630) was significantly reduced in palatal tonsils from IgAN patients compared with chronic tonsillitis. Additionally, bioinformatic analysis showed that Toll-like receptor 4 (TLR4) was the predicted target gene of miR-630 and was regulated by miR-630. When miR-630 was overexpressed in palatal tonsil mononuclear cells from IgAN patients, the expression of TLR4 was reduced and the content of IgA1 in the cell culture supernatant was decreased, and the level of galactosylation in the IgA1 hinge region was increased. Moreover, immunohistochemical analysis showed that the expression of TLR4 in IgAN patients was significantly increased. After knocking down the expression of TLR4, both the concentration of IgA1 and the binding force of IgA1 with broad bean lectin were significantly reduced in IgAN. Furthermore, the mechanism study demonstrated that TLR4 might regulate the expression of IL-1ß and IL-8 through NF-κB signaling pathway to modulate the concentration of IgA1 and the glycosylation level of IgA1. This interesting finding may offer new insight into the molecular mechanism of IgAN.

Potential diagnostic biomarkers for IgA nephropathy: a comparative study pre- and post-tonsillectomy.

OBJECTIVE: The proteins BAFF, ST6GALNAC2, C1GALT1, and COSMC in peripheral blood mononuclear cells (PBMCs) and plasma levels of IgA1 and galactose-deficient IgA1 (Gd-IgA1) are potential biomarkers for IgAN nephropathy. In this study, we comparatively studied the changes of those biomarkers before and after tonsillectomy. METHODS: Peripheral blood samples were obtained from 16 IgAN patients with pre- and post-tonsillectomy. IgAN was diagnosed based on results from analysis of percutaneous renal biopsy tissue. Peripheral blood samples from three patients without renal diseases (non-IgAN), before and after tonsillectomy, and 16 healthy controls were also examined. BAFF, ST6GALNAC2, C1GALT1, and COSMC mRNA levels in PBMCs were detected using real-time PCR. Plasma IgA1 content was measured by ELISA. Gd-IgA1 levels were determined using the VV lectin-ELISA method. RESULTS: BAFF, ST6GALNAC2, C1GALT1, and COSMC mRNA levels and the plasma concentrations of IgA1 and Gd-IgA1 in IgAN patients before tonsillectomy were significantly higher than those in healthy controls (P < 0.05). Tonsillectomy significantly increased the expression of BAFF and ST6GALNAC2, and plasma IgA1 level, while it downregulated that of C1GALT1 and COSMC (P < 0.05). However, in non-IgAN patients, tonsillectomy did not affect the mRNA levels of BAFF, ST6GALNAC2, C1GALT1, and COSMC, plasma IgA1 content and Gd-IgA1 level. Positive correlations were established between BAFF and IgA1 (r = 0.604, P < 0.01) and between ST6GALNAC2 and Gd-IgA1 (r = 0.623, P < 0.01). CONCLUSIONS: Tonsillectomy changes the mRNA levels of BAFF, ST6GALNAC2, C1GALT1, and COSMC in PBMCs, as well as the plasma IgA1 level in IgAN patients. BAFF and ST6GALNAC2 might regulate IgA1 secretion and O-glycosylation.

Two novel compound heterozygous mutations associated with types I and II protein C deficiency with unusual phenotypes.

INTRODUCTION: We diagnosed two Chinese hereditary PC deficiency families and identified two novel compound heterozygous mutations (p.Arg194Cys/Gly324Ser and p.Glu274X/Asp297His) in the protein C (PROC) gene. The probands were classified as types I and II PC deficiency. The aim of this article is to access the influence of the mutations on PC activity, antigen and protein structure, and to evaluate whether there is abnormal PC localization. MATERIALS AND METHODS: Genomic DNA of all family members was extracted, PCR amplified, and sequenced. The mutant PC expression plasmids were constructed. Expression assays, intracellular localization, and molecular modeling were performed. RESULTS: Proband 1, a type II PC defect, harbored a compound heterozygous mutation, p.Arg194Cys/Gly324Ser in the PROC gene, underwent two thromboembolic events. Expression assays indicated that the p.Arg194Cys mutant lead to decreased PC activity and normal PC Ag levels. Intracellular localization showed that both p.Arg194Cys and p.Gly324Ser co-localized with the endoplasmic reticuli and the Golgi apparatus. Molecular modeling suggested that the p.Gly324Ser mutation disturbed the interaction between the heavy and light chains of the PC protein. Proband 2, a type I PC defect, harbored a compound heterozygous PROC gene mutation, p.Glu274X/Asp297His, presented with recurrent spontaneous abortion and right popliteal vein thrombosis. Expression results were in accordance with the PC changes of the patient, and existed in defective PC transport. Structural model suggested p.Glu274X lead to disulfide bond between heavy and light chain cannot form. CONCLUSIONS: Our results confirm that two novel compound heterozygous PROC gene mutations are causative on the two PC deficiency families.