Search

Distance metric learning has achieved great success in person re-identification. Most existing methods that learn metrics from pairwise constraints suffer the problem of imbalanced data. In this study, the authors present a large margin relative distance learning (LMRDL) method which learns the metric from triplet constraints, so that the problem of imbalanced sample pairs can be bypassed. Different from existing triplet-based methods, LMRDL employs an improved triplet loss that enforces penalisation on the triplets with minimal inter-class distance, and this leads to a more stringent constraint to guide the learning. To suppress the large variations of pedestrian's appearance in different camera views, the authors propose to learn the metric over the intra-class subspace. The proposed method is formulated as a logistic metric learning problem with positive semi-definite constraint, and the authors derive an efficient optimisation scheme to solve it based on the accelerated proximal gradient approach. Experimental results show that the proposed method achieves state-of-the-art performance on three challenging datasets (VIPeR, PRID450S, and GRID). [ABSTRACT FROM AUTHOR]

Background: The morbidity of papillary thyroid microcarcinomas is increasing worldwide. Surgery is the main treatment for papillary thyroid microcarcinomas, and the choice of surgical method partly depends on the T stage of the tumor. However, according to the American Joint Commission on Cancer staging system (7th edition), the T stage of papillary thyroid microcarcinomas with different tumor extent is unclear. We aimed to study the effect of tumor extent and other factors on central lymph node metastasis to explore the relationship between tumor extent and T stage and to identify the risk factors predicting central lymph node metastasis in papillary thyroid microcarcinomas. Methods: We included 1092 patients diagnosed with solitary papillary thyroid microcarcinomas between July 2011 and April 2016. The tumor extent and other central lymph node metastasis risk factors were retrospectively analyzed. Results: Univariate analysis revealed that capsule invasion and extracapsular extension (P = 0.013, <0.001; respectively) were significantly correlated with central lymph node metastasis. On multivariate analysis, extracapsular extension was independent central lymph node metastasis predictors (odds ratio 3.092, 95% CI 1.744-5.484), while capsule invasion was not (odds ratio 1.212, 95% CI 0.890-1.651). In addition, multivariate analysis revealed that male sex, tumor size >5 mm, and age <45 years were independent central lymph node metastasis predictors (odds ratio 2.072, 2.356, 2.302; 95% CI 1.483-2.894, 1.792-3.099, 1.748-3.031; respectively). Conclusions: This study supported that capsule invasion and tumor limited to the thyroid in papillary thyroid microcarcinomas were suitable for the lower T1, that is, capsule invasion in papillary thyroid microcarcinomas might not belong to the minimal extrathyroid extension included in T3 of TNM staging. In addition, patients with risk factors of extrathyroid extension, male sex, age <45 years, or tumor size >5 mm in papillary thyroid microcarcinomas should consider a more aggressive surgical treatment. [ABSTRACT FROM AUTHOR]

Background: Whether sonography is an appropriate imaging modality for cervical lymph nodes in patients with papillary thyroid microcarcinoma (PTMC) remains unclear. Hence, this study aimed to evaluate the diagnostic value of ultrasonography (US) features for lymph node metastasis in PTMC. Methods: Seven hundred twelve patients with PTMC who underwent conventional ultrasonography examinations of the cervical lymph nodes were included. All included cases underwent total thyroidectomy plus prophylactic central lymph node dissection. The included lymph nodes were marked superficially, and the corresponding lymph nodes were completely removed and sent for pathological examination. The US features of lymph nodes with and without metastasis were compared, and the odds ratios of the suspicious US features were determined with univariate and multivariate analyses. Results: Round shape, loss of an echogenic fatty hilum, cystic change, calcification, and abnormal vascularity were significantly more common in metastatic than nonmetastatic lymph nodes, whereas the boundary and echo did not significantly differ. Multivariate logistic regression analysis showed that round shape, loss of echogenic fatty hilum, cystic change, calcification, and abnormal vascularity were independent predictive factors for the assessment of metastatic lymph nodes. Round shape had the highest sensitivity of all variables, while loss of an echogenic fatty hilum had the highest specificity and accuracy. The area under the receiver operating characteristic curve, which was calculated to verify the relationship between the various US features and metastatic lymph nodes, was 0.793. Conclusions: Our study found that the US features of round shape, cystic change, calcification, loss of echogenic fatty hilum, and abnormal vascularity were useful sonographic criteria for differentiating between cervical lymph nodes with and without metastasis. [ABSTRACT FROM AUTHOR]

Background: Proteins in the cofilin pathway regulate actin dynamics and may be involved in cancer cell migration and invasion. However, there are no direct data that suggest that dephosphorylated cofilin can affect breast cancer prognosis. Methods: We assessed the expressions of cofilin and phosphorylated cofilin (P-cofilin) in breast cancer tissue microarrays (290 patients, mean follow-up: 95.7±2.49 months) to evaluate dephosphorylated cofilin and its relationship with breast cancer prognosis. The associations of pathological characteristics with cumulative survival were evaluated using Kaplan-Meier analysis. Results: Univariate analyses revealed that overall survival was associated with cofilin levels, N category, TNM stage, estrogen receptor status, progesterone receptor status, and molecular subtypes. Cofilin status and TNM stage independently affected overall survival, although P-cofilin expression was not associated with patient survival. In the P-cofilin-negative subgroup, cofilin expression was significantly associated with patient survival, although cofilin expression was not significantly associated with patient survival in the P-cofilin-positive subgroup. We further analyzed the P-cofilin-negative cases and found that Ki-67 expression was significantly elevated in the subgroup that was strongly positive for cofilin (P=0.002). Conclusion: Among P-cofilin-negative patients with breast cancer, cofilin expression defines a population of patients with lower overall survival, which suggests that dephosphorylated cofilin expression might predict the prognosis in cases of P-cofilin-negative breast cancer. Furthermore, our results suggest that inhibitors of dephosphorylated cofilin expression may provide therapeutic benefits in patients with breast cancer. [ABSTRACT FROM AUTHOR]

Background: The objective of this study is to perform a meta-analysis to evaluate the associations between the BRAFV600E mutation status and aggressive clinicopathological features and poor prognostic factors in papillary thyroid cancer. Methods: A literature search was performed within the PubMed, MEDLINE, Web of Science databases, and EMBASE databases using the Medical Subject Headings and keywords from January 2003 to July 2015. Individual study-specific odds ratios and confidence intervals were calculated, as were the Mantel-Haenszel pooled odds ratios for the combined studies. Results: Sixty-three studies of 20,764 patients were included in the final analysis. Compared with wild-type BRAF, the BRAFV600E mutation was associated with aggressive clinicopathological factors, including extrathyroidal extension, higher TNM stage, lymph node metastasis, and recurrence, and was associated with reduced overall survival; however, there was no significant association between the presence of BRAF mutation and distant metastasis. Conclusions: BRAF mutations are closely associated with aggressive clinicopathological characteristics and poorer prognosis in papillary thyroid cancer. Accordingly, aggressive treatment should be considered for papillary thyroid cancer patients with BRAF mutation. [ABSTRACT FROM AUTHOR]

The problem of iterative learning control (ILC) is considered for a class of time-varying systems with random packet dropouts. It is assumed that an ILC scheme is implemented via a remote control system and that packet dropout occurs during the packet transmission between the ILC controller and the actuator of remote plant. The packet dropout is viewed as a binary switching sequence which is subject to the Bernoulli distribution. In order to eliminate the effect of packet dropouts on the convergence property of output error, the hold-input scheme is adopted to compensate the packet dropout at the actuator. It is shown that the hold-input scheme with average ILC can achieve asymptotical convergence along the iteration axis for discrete time-varying linear system. Numerical examples are provided to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Background: Genome-wide association studies have reported that a polymorphism near the estrogen receptor gene (ESR1) (rs2046210) is associated with a risk of breast cancer, with the A allele conferring an increased risk. However, considering the controversial results from more recent replicated studies, we conducted a case-control study in an independent Chinese Han population and a meta-analysis to clarify the association of this polymorphism with breast cancer risk. Method and Findings: A hospital-based case-control study including 461 cases and 537 controls from a Chinese Han population was conducted initially, and this study showed that the rs2046210 A allele was significantly associated with breast cancer risk, with an OR of 1.32 (95% CI = 1.10-1.59). Subsequently, a meta-analysis integrating the current study and previous publications with a total of 53,379 cases and 55,493 controls was performed to further confirm our findings. Similarly, a significant association between this polymorphism and breast cancer risk was also observed in the overall population especially among Asians, with ORs for per A allele of 1.14 (95% CI = 1.10-1.18) in the overall population and 1.27 (95% CI = 1.23-1.31) in the Asian population. Conclusion: Our results provide strong evidence to support that the common polymorphism near the ESR1 gene, rs2046210, is associated with an increased risk of breast cancer in Asian and European populations but not in Africans, although the biological mechanisms need to be further investigated. [ABSTRACT FROM AUTHOR]

Iterative learning control (ILC) is applied to remote control systems in which communication channels from the plant to the controller are subject to random data dropout and communication delay. Through analysis, it is shown that ILC can achieve asymptotical convergence along the iteration axis, as far as the probabilities of the data dropout and communication delay are known a priori. Owing to the essence of feed forward-based control ILC can perform trajectory-tracking tasks while both the data- dropout and the one-step delay phenomena are taken into consideration. Theoretical analysis and simulations validate the effectiveness of the ILC algorithm for network- based control tasks. [ABSTRACT FROM AUTHOR]

VEGF (vascular endothelial growth factor) is a critical regulator in angiogenesis through binding to its specific receptors, including VEGFR-2 (VEGF receptor 2), a kinase insert domain-containing receptor, on the surface of endothelial cells. As angiogenesis has been shown to be essential for malignancy of tumours, VEGFR-2 is a potential therapeutic target for the treatment of cancers. To explore this potential, VEGFR-2-CD (the protein tyrosine kinase catalytic domain of VEGFR-2) was cloned and expressed in Streptomyces lividans TK24, a prokaryotic expression system. The recombinant protein was purified, and correlations between its activity and enzyme concentration, ATP concentration, substrate concentration and bivalent cations were characterized. An ELISA-based screening system was then established and used to search for inhibitors acting on the tyrosine kinase part of VEGFR-2. More than 600 compounds originating from a variety of microbes have been screened so far, and a number of them have been demonstrated to be potential inhibitors of VEGFR-2 TK. [ABSTRACT FROM AUTHOR]

A series of N-substituted 4-amino-6,7,8-trimethoxyquinazoline derivatives has been synthesized from 4-chloro-6,7,8-trimethoxyquinazoline and aryl (or benzyl) amines using 2-propanol as a solvent. The starting material 4-chloro-6,7,8-trimethoxyquinazoline has been synthesized from natural gallic acid by a novel route. Their structures have been verified by elemental analysis and IR, 1H, and 13C NMR spectroscopy. The title compounds have been evaluated for their in vitro antiproliferative activities against some cancer cells by the MTT method. Unfortunately, most of the compounds tested have exhibited a weaker anticancer activity than the reference standard drug PD153035. [ABSTRACT FROM AUTHOR]

A two-dimensional model is presented as a way to hydrogeologically characterize the controlling factors in the Sanshandao Gold Mine. The finite element method was first applied to simulate the ground water system of the current operation, using leakage data and the calculated recharge. An inverse model was applied to the observed data (e.g., head and discharge) to verify and calibrate the ground water simulation model and to estimate the hydrogeological parameters for the water-bearing zones. Nonlinear mathematic programming was used to solve the inverse model and to estimate the model parameters in 17 districts with different hydrogeological characteristics. The finite element equations were solved by means of a large non-symmetrical sparse equation. The results were in agreement with what is currently observed in the mine. The models and the estimated parameters were then applied to predict the mine water discharge for drifts extending to depths of −330 to −600 m during the next development stage. In order to improve the predicted accuracy of the numerical model, an iterative element mesh was added in the districts near the drainage drifts so that the computed discharges that flowed into the drifts would approach the recharges that flow into the borders of the mine. The model was also used to understand how the mine discharge would be influenced by factors such as unsteady ground water flow and the construction of hydraulic barriers to restrict ground water from entering the pits. [ABSTRACT FROM AUTHOR]

The Sanshandao Gold Mine is one of the largest gold mines in China, and is almost completely surrounded by seawater. Factors such as water-controlling structures and water-bearing zones that developed in the mine were studied, based on geophysical exploration data and hydrogeological investigations of the wells and drifts of the mine. The sources of recharge (seawater, brine from surface runoff, and Quaternary water) were proportionally determined based on 18O isotopic and water quality data measured for each drainage point in the pits. Appropriate boundary conditions were defined for the recharge source of the seawater and natural runoff brine. The hydraulic connections among the water-bearing zones were also considered. This work was conducted to prepare for future mine development and allowed us to simulate anticipated ground water flow. [ABSTRACT FROM AUTHOR]

The diversity of microbial communities in rhizosphere soil and non-rhizosphere soil was investigated in Juglans mandshurica plantation in Liaodong Mountain, and the relationship between the diversity and physical or chemical characteristics of soil were also studied. The results showed that most of chemical characteristics such as pH, total carbon, total nitrogen, total phosphorus and available phosphorus in rhizosphere soils were higher than that in non-rhizosphere soils significantly. The main factors affecting soil bacterial and fungal community structure are soil pH and available phosphorus (bacteria) and available nitrogen (fungi), respectively. Significant difference in the number of biomaker between rhizosphere and non-rhizosphere soils was detected for fungal, but not for bacteria. On contrast, significant difference of the diversity indexes between rhizosphere and non-rhizosphere soils were detected for bacteria, but not for fungi. These differences between rhizosphere and non-rhizosphere soils, and also between bacteria and fungi might caused by roots physiological metabolism of J. mandshurica. The dominant microbial groups are Actinobacteriota, Proteobacteria and Acidobacteriota (bacteria) and Ascomycota (fungi), which accounted for about 80% of relative abundance of bacteria or fungi. These results will provide the theoretical and scientific basis for the sustainable management and improvement of soil fertility of J. mandshurica plantation. [ABSTRACT FROM AUTHOR]

Background: Extracellular vesicles (EVs) derived from tumor cells are implicated in the progression of malignancies through the transfer of molecular cargo microRNAs (miRNAs or miRs). We aimed to explore the role of EVs derived from breast cancer cells carrying miR-182-5p in the occurrence and development of breast cancer. Methods: Diferentially expressed miRNAs and their downstream target genes related to breast cancer were screened through GEO and TCGA databases. miR-182-5p expression was examined in cancer tissues and adjacent normal tissues from patients with breast cancer. EVs were isolated from breast cancer cell line MDA-MB-231 cells and identifed. The gain- and loss-of function approaches of miR-182-5p and CKLF-like MARVEL transmembrane domaincontaining 7 (CMTM7) were performed in MDA-MB-231 cells and the isolated EVs. Human umbilical vein endothelial cells (HUVECs) were subjected to co-culture with MDA-MB-231 cell-derived EVs and biological behaviors were detected by CCK-8 assay, fow cytometry, immunohistochemical staining, Transwell assay and vessel-like tube formation in vitro. A xenograft mouse model in nude mice was established to observe the tumorigenesis and metastasis of breast cancer cells in vivo. Results: miR-182-5p was highly expressed in breast cancer tissues and cells, and this high expression was associated with poor prognosis of breast cancer patients. miR-182-5p overexpression was shown to promote tumor angiogenesis in breast cancer. Moreover, our data indicated that miR-182-5p was highly enriched in EVs from MDA-MD-231 cells and then ultimately enhanced the proliferation, migration, and angiogenesis of HUVECs in vitro and in vivo. Moreover, we found that CMTM7 is a target of miR-182-5p. EVs-miR-182-5p promotes tumorigenesis and metastasis of breast cancer cells by regulating the CMTM7/EGFR/AKT signaling axis. Conclusions: Taken altogether, our fndings demonstrates that EVs secreted by breast cancer cells could carry miR182-5p to aggravate breast cancer through downregulating CMTM7 expression and activating the EGFR/AKT signaling pathway [ABSTRACT FROM AUTHOR]

Objective: To elucidate the potential molecular mechanism by which Fuzheng Kang'ai decoction (, FZKA) inhibits proliferation, migration, and invasion of lung cancer cells., Methods: Varying FZKA concentrations were used to manage lung cancer cells (A549 and PC9). We employed: cell counting kit-8 (CCK-8) and plate clone for-mation assays to examine the cell viability; flow cytometry (FCM) to analyze the cycle arrest; transwell and wound-healing assays to assess the cell invasion and migration, respectively. Further, a quantitative real-time polymerase chain reaction (qRT-PCR) assay was adopted to evaluate the miR-21-5p expression. For protein expression analysis, we employed the Western blot technique. Recombinant miR-21-5p overexpression adenovirus vector harboring GFP was constructed and transfected into A549 and PC9, after which we explored the effect of FZKA on miR-21-5p overexpression., Results: Notably, treatment with FZKA inhibited viability, clone-formation ability, invasion, and migration of lung cancer cells. Mechanistically, FZKA markedly suppressed miR-21-5p expression but elevated the human phosphatase and tensin homology deleted on chromosome ten (PTEN) protein level in both A549 and PC9 cells. Over-expression of miR-21-5p lowered PTEN protein expression. Besides, overexpressed miR-21-5p levels with adenovirus antagonized FZKA-upregulated PTEN protein expression., Conclusion: The present study demonstrates how FZKA modulates cell biological behaviors, for instance, it impedes the proliferation by upregulating PTEN expression with miR-21-5p as the target. These findings unveil the potential novel molecular mechanisms from the microRNA aspect by which FZKA suppresses the growth of human lung cancer cells.