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221.
Breast cancer recurrence (BCR) is a common treatment outcome despite curative-intent primary treatment of non-metastatic breast cancer. Currently used prognostic and predictive factors utilize tumor-based markers, and are not optimal determinants of risk of BCR. Germline-based copy number aberrations (CNAs) have not been evaluated as determinants of predisposition to experience BCR. In this study, we accessed germline DNA from 369 female breast cancer subjects who received curative-intent primary treatment following diagnosis. Of these, 155 experienced BCR and 214 did not, after a median duration of follow up after breast cancer diagnosis of 6.35 years (range = 0.60–21.78) and 8.60 years (range = 3.08–13.57), respectively. Whole genome CNA genotyping was performed on the Affymetrix SNP array 6.0 platform. CNAs were identified using the SNP-Fast Adaptive States Segmentation Technique 2 algorithm implemented in Nexus Copy Number 6.0. Six samples were removed due to poor quality scores, leaving 363 samples for further analysis. We identified 18,561 CNAs with ≥1 kb as a predefined cut-off for observed aberrations. Univariate survival analyses (log-rank tests) identified seven CNAs (two copy number gains and five copy neutral-loss of heterozygosities, CN-LOHs) showing significant differences (P<2.01×10−5) in recurrence-free survival (RFS) probabilities with and without CNAs.We also observed three additional but distinct CN-LOHs showing significant differences in RFS probabilities (P<2.86×10−5) when analyses were restricted to stratified cases (luminal A, n = 208) only. After adjusting for tumor stage and grade in multivariate analyses (Cox proportional hazards models), all the CNAs remained strongly associated with the phenotype of BCR. Of these, we confirmed three CNAs at 17q11.2, 11q13.1 and 6q24.1 in representative samples using independent genotyping platforms. Our results suggest further investigations on the potential use of germline DNA variations as prognostic markers in cancer-associated phenotypes.  相似文献   
222.

Background

Radiographic evaluation for patients with scoliosis using Cobb method is the current gold standard, but radiography has radiation hazards. Several groups have recently demonstrated the feasibility of using 3D ultrasound for the evaluation of scoliosis. Ultrasound imaging is radiation-free, comparatively more accessible, and inexpensive. However, a reliable and valid 3D ultrasound system ready for clinical scoliosis assessment has not yet been reported. Scolioscan is a newly developed system targeted for scoliosis assessment in clinics by using coronal images of spine generated by a 3D ultrasound volume projection imaging method. The aim of this study is to test the reliability of spine deformity measurement of Scolioscan and its validity compared to the gold standard Cobb angle measurements from radiography in adolescent idiopathic scoliosis (AIS) patients.

Methods

Prospective study divided into two stages: 1) Investigation of intra- and inter- reliability between two operators for acquiring images using Scolioscan and among three raters for measuring spinal curves from those images; 2) Correlation between the Cobb angle obtained from radiography by a medical doctor and the spine curve angle obtained using Scolioscan (Scolioscan angle). The raters for ultrasound images and the doctors for evaluating radiographic images were mutually blinded. The two stages of tests involved 20 (80 % females, total of 26 angles, age of 16.4?±?2.7 years, and Cobb angle of 27.6?±?11.8°) and 49 (69 % female, 73 angles, 15.8?±?2.7 years and 24.8?±?9.7°) AIS patients, respectively. Intra-class correlation coefficients (ICC) and Bland-Altman plots and root-mean-square differences (RMS) were employed to determine correlations, which interpreted based on defined criteria.

Results

We demonstrated a very good intra-rater and intra-operator reliability for Scolioscan angle measurement with ICC larger than 0.94 and 0.88, respectively. Very good inter-rater and inter-operator reliability was also demonstrated, with both ICC larger than 0.87. For the thoracic deformity measurement, the RMS were 2.5 and 3.3° in the intra- and inter-operator tests, and 1.5 and 3.6° in the intra- and inter-rater tests, respectively. The RMS differences were 3.1, 3.1, 1.6, 3.7° in the intra- and inter-operator and intra- and inter-rater tests, respectively, for the lumbar angle measurement. Moderate to strong correlations (R2?>?0.72) were observed between the Scolioscan angles and Cobb angles for both the thoracic and lumbar regions. It was noted that the Scolioscan angle slightly underestimated the spinal deformity in comparison with Cobb angle, and an overall regression equation y?=?1.1797x (R2?=?0.76) could be used to translate the Scolioscan angle (x) to Cobb angle (y) for this group of patients. The RMS difference between Scolioscan angle and Cobb angle was 4.7 and 6.2°, with and without the correlation using the overall regression equation.

Conclusions

We showed that Scolioscan is reliable for measuring coronal deformity for patients with AIS and appears promising in screening large numbers of patients, for progress monitoring, and evaluation of treatment outcomes. Due to it being radiation-free and relatively low-cost, Scolioscan has potential to be widely implemented and may contribute to reducing radiation dose during serial monitoring.
  相似文献   
223.
S100 calcium binding protein B (S100B), a well-studied marker for neurologic injury, has been suggested as a candidate for predicting outcome after subarachnoid hemorrhage. We performed a pooled analysis summarizing the associations between S100B protein in serum and cerebrospinal fluid (CSF) with radiographic vasospasm, delayed ischemic neurologic deficit (DIND), delayed cerebral infarction, and Glasgow Outcome Scale (GOS) outcome. A literature search using PubMed, the Cochrane Library, and the EMBASE databases was performed to identify relevant studies published up to May 2015. The weighted Stouffer’s Z method was used to perform a pooled analysis of outcome measures with greater than three studies. A total of 13 studies were included in this review. Higher serum S100B level was found to be associated with cerebral infarction as diagnosed by CT (padj = 3.1 x 10−4) and worse GOS outcome (padj = 5.5 x 10−11). There was no association found between serum and CSF S100B with radiographic vasospasm or DIND. S100B is a potential prognostic marker for aSAH outcome.  相似文献   
224.
Self‐assembled vertical heterostructure with a high interface‐to‐volume ratio offers tremendous opportunities to realize intriguing properties and advanced modulation of functionalities. Here, a heterostructure composed of two visible‐light photocatalysts, BiFeO3 (BFO) and ε‐Fe2O3 (ε‐FO), is designed to investigate its photoelectrochemical performance. The structural characterization of the BFO‐FO heterostructures confirms the phase separation with BFO nanopillars embedded in the ε‐FO matrix. The investigation of band structure of the heterojunction suggests the assistance of photoexcited carrier separation, leading to an enhanced photoelectrochemical performance. The insights into the charge separation are further revealed by means of ultrafast dynamics and electrochemical impedance spectroscopies. This work shows a delicate design of the self‐assembled vertical heteroepitaxy by taking advantage of the intimate contact between two phases that can lead to a tunable charge interaction, providing a new configuration for the optimization of photoelectrochemical cell.  相似文献   
225.

Background

Recent data have shown that γδ T cells can act as mediators for immune defense against tumors. Our previous study has demonstrated that persisting clonally expanded TRDV4 T cells might be relatively beneficial for the outcome of patients with T cell acute lymphoblastic leukemia after hematopoietic stem cell transplantation (HSCT). However, little is known about the distribution and clonality of the TRDV repertoire in T cell receptor (TCR) of γδ T cells and their effects on the clinical outcome of patients with acute myeloid leukemia (AML). The aim of this study was to assess whether the oligoclonal expansion of TCR Vδ T cells could be used as an immune biomarker for AML outcome.

Findings

γδ T cells were sorted from the peripheral blood of 30 patients with untreated AML and 12 healthy donors. The complementarity-determining region 3 (CDR3) sizes of eight TCR Vδ subfamily genes (TRDV1 to TRDV8) were analyzed in sorted γδ T cells using RT-PCR and GeneScan. The most frequently expressed TRDV subfamilies in the AML patients were TRDV8 (86.67 %) and TRDV2 (83.33 %), and the frequencies for TRDV1, TRDV3, TRDV4, and TRDV6 were significantly lower than those in healthy individuals. The most frequent clonally expanded TRDV subfamilies in the AML patients included TRDV8 (56.67 %) and TRDV4 (40 %). The clonal expansion frequencies of the TRDV2 and TRDV4 T cells were significantly higher than those in healthy individuals, whereas a significantly lower TRDV1 clonal expansion frequency was observed in those with AML. Moreover, the oligoclones of TRDV4 and TRDV8 were independent protective factors for complete remission. Furthermore, the oligoclonal expansion frequencies of TRDV5 and TRDV6 in patients with relapse were significantly higher than those in non-recurrent cases.

Conclusions

To the best of our knowledge, we characterized for the first time a significant alteration in the distribution and clonality of the TRDV subfamily members in γδ T cells sorted from AML patients. Clonally expanded TRDV4 and TRDV8 T cells might contribute to the immune response directed against AML, while oligoclonal TRDV5 and TRDV6 might occur in patients who undergo relapse. While the function of such γδ T cell clones requires further investigation, TRDV γδ T cell clones might be potential immune biomarkers for AML outcome.
  相似文献   
226.
BackgroundDiabetes is a well-known risk factor for tuberculosis (TB) and is increasingly prevalent in low- and middle-income countries, where the burden of TB is high. Glycemic control has the potential to modify the risk of TB. However, there are few studies on the association between glycemic control and TB risk, and the results are inconsistent.ConclusionsGood glycemic control could potentially modify the risk of TB among diabetic patients and may contribute to the control of TB in settings where diabetes and TB are prevalent.  相似文献   
227.
Aminopeptidase N (APN) is a zinc-dependent ectopeptidase involved in cell proliferation, secretion, invasion, and angiogenesis, and is widely recognized as an important cancer target. However, the mechanisms whereby ligands leave the active site of APN remain unknown. Investigating ligand dissociation processes is quite difficult, both in classical simulation methods and in experimental approaches. In this study, random acceleration molecular dynamics (RAMD) simulation was used to investigate the potential dissociation pathways of ligand from APN. The results revealed three pathways (channels A, B and C) for ligand release. Channel A, which matches the hypothetical channel region, was the most preferred region for bestatin to dissociate from the enzyme, and is probably the major channel for the inner bound ligand. In addition, two alternative channels (channels B and C) were shown to be possible pathways for ligand egression. Meanwhile, we identified key residues controlling the dynamic features of APN channels. Identification of the dissociation routes will provide further mechanistic insights into APN, which will benefit the development of more promising APN inhibitors.
Graphical Abstract The release pathways of bestatin inside active site of aminopeptidase N were simulated using RAMD simulation
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228.
Nuclear antigens are known to trigger off innate and adaptive immune responses. Recent studies have found that the complex of nucleic acids and core histones that are derived from damaged cells may regulate allergic responses. However, no fundamental study has been performed concerning the role of linker histone H1 in mast cell-mediated type I hyperreactivity. In this study, we explored the impact of histone H1 on mast cell-mediated allergic responses both in vitro and in vivo. In the course of a bona-fide experimental allergen sensitization model upon co-injection with alum adjuvant, ovalbumin (OVA), but not PBS, induced elevated levels of circulating histone H1. Intranasal challenge with histone H1 to OVA/alum- (but not PBS/alum)-sensitized mice induced significantly severer symptoms of allergic rhinitis than those in mice sensitized and challenged with OVA. A monoclonal antibody against histone H1 not only suppressed mast cell degranulation, but also ameliorated OVA-induced nasal hyperreactivity and IgE-mediated passive cutaneous anaphylaxis. Our present data suggest that nuclear histone H1 represents an alarmin-like endogenous mediator acting on mast cells, and that its blockage has a therapeutic potential for mast cell-mediated type I hyperreactivity.  相似文献   
229.
BackgroundAnthrax, a global re-emerging zoonotic disease in recent years is enzootic in mainland China. Despite its significance to the public health, spatiotemporal distributions of the disease in human and livestock and its potential driving factors remain poorly understood.Conclusions/SignificanceAnthrax in China was characterized by significant seasonality and spatial clustering. The spatial distribution of human anthrax was largely driven by livestock husbandry, human density, land cover, elevation, topsoil features and climate. Enhanced surveillance and intervention for livestock and human anthrax in the high-risk regions, particularly on the Qinghai-Tibetan Plateau, is the key to the prevention of human infections.  相似文献   
230.
Many modern filtration technologies are incapable of the complete removal of Cryptosporidium oocysts from drinking-water. Consequently, Cryptosporidium-contaminated drinking-water supplies can severely implicate both water utilities and consumers. Existing methods for the detection of Cryptosporidium in drinking-water do not discern between non-pathogenic and pathogenic species, nor between viable and non-viable oocysts. Using FluidFM, a novel force spectroscopy method employing microchannelled cantilevers for single-cell level manipulation, we assessed the size and deformability properties of two species of Cryptosporidium that pose varying levels of risk to human health. A comparison of such characteristics demonstrated the ability of FluidFM to discern between Cryptosporidium muris and Cryptosporidium parvum with 86% efficiency, whilst using a measurement throughput which exceeded 50 discrete oocysts per hour. In addition, we measured the deformability properties for untreated and temperature-inactivated oocysts of the highly infective, human pathogenic C. parvum to assess whether deformability may be a marker of viability. Our results indicate that untreated and temperature-inactivated C. parvum oocysts had overlapping but significantly different deformability distributions.  相似文献   
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