[Advantages and Application Prospects of Deep Learning in Image Recognition and Bone Age Assessment]

Deep learning and neural network models have been new research directions and hot issues in the fields of machine learning and artificial intelligence in recent years. Deep learning has made a breakthrough in the applications of image and speech recognitions, and also has been extensively used in the fields of face recognition and information retrieval because of its special superiority. Bone X-ray images express different variations in black-white-gray gradations, which have image features of black and white contrasts and level differences. Based on these advantages of deep learning in image recognition, we combine it with the research of bone age assessment to provide basic datum for constructing a forensic automatic system of bone age assessment. This paper reviews the basic concept and network architectures of deep learning, and describes its recent research progress on image recognition in different research fields at home and abroad, and explores its advantages and application prospects in bone age assessment.

[Diagnostic Value of Postmortem CT Angiography in Coronary Atherosclerosis]

OBJECTIVES

To explore the application value of postmortem computed tomography （CT） angiography on diagnosis of coronary atherosclerotic stenosis degree.

METHODS

Based on the previous experimental results, the postmortem CT angiography device of human isolated heart was improved. Different coronary atherosclerotic stenosis degree of sudden death cases was selected. Before the cardiac anatomy, hearts were removed out completely and CT angiography was performed immediately. The CT angiography results were compared with histopathological findings. Meanwhile, the advantages and disadvantages of the angiography device before and after improvement were compared.

RESULTS

The improved angiography device of isolated heart could get better imaging results. The postmortem CT angiography results had high consistency with the histopathological findings on diagnosis of coronary atherosclerotic stenosis degree. And the coronary artery lesions could be revealed more objectively and vividly by 3D reconstruction technology. However, CT angiography could only be used to examine the pathological changes of blood vessels, which might have some limitations on the diagnosis of cause of death.

CONCLUSIONS

Postmortem CT angiography can be used as an additional method for the conventional autopsy in the cases of coronary atherosclerosis.

Mimicking Embedded Vasculature Structure for 3D Cancer on a Chip Approaches through Micromilling

The ability for cells to sense and respond to microenvironmental signals is influenced by their three dimensional (3D) surroundings, which includes the extracellular matrix (ECM). In the 3D environment, vascular structures supply cells with nutrients and oxygen thus affecting cell responses such as motility. Interpretation of cell motility studies though is often restricted by the applied approaches such as 2D conventional soft lithography methods that have rectangular channel cross-sectional morphology. To better simulate cell responses to vascular supply in 3D, we developed a cell on a chip system with microfluidic channels with curved cross-sections embedded within a 3D collagen matrix that emulates anatomical vasculature more closely than inorganic polymers, thus to mimic a more physiologically relevant 3D cellular environment. To accomplish this, we constructed perfusable microfluidic channels by embedding sacrificial circular gelatin vascular templates in collagen, which were removed through temperature control. Motile breast cancer cells were pre-seeded into the collagen matrix and when presented with a controlled chemical stimulation from the artificial vasculature, they migrated towards the vasculature structure. We believe this innovative vascular 3D ECM system can be used to provide novel insights into cellular dynamics during multidirectional chemokineses and chemotaxis that exist in cancer and other diseases.

[Effect of ear point embedding on plasma and effect site concentrations of propofol-remifentanil in elderly patients after target-controlled induction]

OBJECTIVE

To observe the clinical effect of ear point embedding on plasma and effect site concentrations of propofol-remifentanil in elderly patients who underwent abdominal external hernia surgery at the time of consciousness and pain disappearing by target-controlled infusion (TCI) and bispectral index (BIS).

METHODS

Fifty patients who underwent elective abdominal hernia surgery were randomly assigned into an observation group and a control group, 25 cases in each one. In the observation group, 30 minutes before anesthesia induction, Fugugou (Extra), Gan (CO₁₂), Pizhixia (AT₄), and Shenmen (TF₄) were embedded by auricular needles until the end of surgery, 10 times of counter press each point. In the control group, the same amount of auricular tape was applied until the end of surgery at the same points without stimulation 30 minutes before anesthesia induction. Patients in the two groups were given total intravenous anesthesia, and BIS was monitored by BIS anesthesia depth monitor. Propofol was infused by TCI at a beginning concentration of 1.5μg/L and increased by 0.3μg/L every 30s until the patients lost their consciousness. After that, remifentanil was infused by TCI at a beginning concentration of 2.0μg/L and increased by 0.3μg/L every 30s until the patients had no body reaction to pain stimulation (orbital reflex). Indices were recorded, including mean arterial pressure (MAP), heart rate (HR) and the BIS values, at the time of T₀ (entering into the operation room), T₁ (losing consciousness) and T₂ (pain relief), the plasma and effect site concentrations of propofol at T₁, the plasma and effect site concentrations of remifentanil at T₂. After surgery we recorded the total amounts of propofol and remifentanil, surgery time and anesthesia time.

RESULTS

At T₁ and T₂, MAP and HR of the observation group were higher than those of the control group (P<0.05, P<0.01). At T₁, the plasma and effect site concentrations of propofol in the observation group were significantly lower than those in the control group (P<0.05, P<0.01). At T₂, the plasma and effect site concentrations of remifentanil in the observation group were significantly lower than those in the control group (P<0.05, P<0.01). There was no significant difference in BIS values at T₁ and T₂ between the two groups (bothP>0.05). There was no significant difference in operation time and anesthesia time between the two groups (bothP>0.05). The total amount of remifentanil in the observation group was significantly lower than that in the control group (P<0.01). There was no significant difference in the total amount of propofol between the two groups (P>0.05).

CONCLUSIONS

Ear points embedding combined with propofol-remifentanil TCI could reduce the plasma and effect site concentrations of propofol and remifentanil and the total amount of remifentanil in elderly patients with extra-abdominal hernia surgery, and had the effect of assisting sedation and analgesia.

Molecular Coupling of Histone Crotonylation and Active Transcription by AF9 YEATS Domain

Recognition of histone covalent modifications by chromatin-binding protein modules ("readers") constitutes a major mechanism for epigenetic regulation, typified by bromodomains that bind acetyllysine. Non-acetyl histone lysine acylations (e.g., crotonylation, butyrylation, propionylation) have been recently identified, but readers that prefer these acylations have not been characterized. Here we report that the AF9 YEATS domain displays selectively higher binding affinity for crotonyllysine over acetyllysine. Structural studies revealed an extended aromatic sandwiching cage with crotonyl specificity arising from π-aromatic and hydrophobic interactions between crotonyl and aromatic rings. These features are conserved among the YEATS, but not the bromodomains. Using a cell-based model, we showed that AF9 co-localizes with crotonylated histone H3 and positively regulates gene expression in a YEATS domain-dependent manner. Our studies define the evolutionarily conserved YEATS domain as a family of crotonyllysine readers and specifically demonstrate that the YEATS domain of AF9 directly links histone crotonylation to active transcription.

ENL links histone acetylation to oncogenic gene expression in acute myeloid leukaemia

Cancer cells are characterized by aberrant epigenetic landscapes and often exploit chromatin machinery to activate oncogenic gene expression programs¹. Recognition of modified histones by “reader” proteins constitutes a key mechanism underlying these processes; therefore, targeting such pathways holds clinical promise, as exemplified by the development of BET bromodomain inhibitors^{2, 3}. We recently identified the YEATS domain as a novel acetyllysine-binding module⁴, yet its functional importance in human cancer remains unknown. Here we show that the YEATS domain-containing protein ENL, but not its paralog AF9, is required for disease maintenance in acute myeloid leukaemia (AML). CRISPR-Cas9 mediated depletion of ENL led to anti-leukemic effects, including increased terminal myeloid differentiation and suppression of leukaemia growth in vitro and in vivo. Biochemical and crystal structural studies and ChIP-seq analyses revealed that ENL binds to acetylated histone H3, and colocalizes with H3K27ac and H3K9ac on the promoters of actively transcribed genes that are essential for leukaemias. Disrupting the interaction between the YEATS domain and histone acetylation via structure-based mutagenesis reduced RNA polymerase II recruitment to ENL target genes, leading to suppression of oncogenic gene expression programs. Importantly, disruption of ENL’s functionality further sensitized leukaemia cells to BET inhibitors. Together, our study identifies ENL as a histone acetylation reader that regulates oncogenic transcriptional programs in AML and suggests that displacement of ENL from chromatin may be a promising epigenetic therapy alone or in combination with BET inhibitors for AML.

Apoptosis, proliferation, and morphology during vein graft remodeling in rabbits

Neo-intima development and atherosclerosis limit the long-term use of vein grafts for revascularization of ischemic tissues. Recently, studies have confirmed that proliferating cell nuclear antigen (PCNA) plays an important role in cell proliferation. Our research confirmed that 28 days after vein transplantation, PCNA expression increases significantly. Using rabbits, rather than rodents, for a more representative model of human vein grafts, we aimed to establish a time course of changes in cell proliferation and apoptosis using morphometric and immunohistochemical analyses, western blot, terminal deoxynucleotidyl transferase dUTP nick end labeling, and transmission electron microscopy (TEM). The external jugular veins of 42 healthy purebred male New Zealand white rabbits were grafted onto their common carotid arteries. The rabbits were divided into seven groups, with vein grafts being harvested before surgery, and at 1, 3, 7, 14, 28, and 90 days afterwards. The extent of stenosis and apoptosis, PCNA protein levels, and TEM morphology were subsequently examined. Intimal thickness was slightly decreased 1 day following surgery, but then increased continuously until the 90th day. Western blot and immunohistochemistry both indicated lowered PCNA expression on day 1, although levels subsequently increased, peaking at 7 days post-surgery. After surgery, apoptosis was lowest on day 7, and remained low thereafter. TEM revealed signs of apoptosis as vein graft restenosis progressed. Proliferation and apoptosis co-occurred following grafting, indicating that both processes were involved in vein graft remodeling. Apoptosis levels were highest between days 1 and 3 after surgery, whereas proliferation culminated on the 7th day.

Fracture risk and bone mineral density levels in patients with systemic lupus erythematosus: a systematic review and meta-analysis

Previous studies suggested possible bone loss and fracture risk in patients with systemic lupus erythematosus (SLE). The aim of this systematic review and meta-analysis was to assess the strength of the relationship of SLE with fracture risk and the mean difference of bone mineral density (BMD) levels between SLE patients and controls. Literature search was undertaken in multiple indexing databases on September 26, 2015. Studies on the relationship of SLE with fracture risk and the mean difference of BMD levels between SLE patients and controls were included. Data were combined using standard methods of meta-analysis. Twenty-one studies were finally included into the meta-analysis, including 15 studies on the mean difference of BMD levels between SLE patients and controls, and 6 studies were on fracture risk associated with SLE. The meta-analysis showed that SLE patients had significantly lower BMD levels than controls in the whole body (weighted mean difference [WMD] = -0.04; 95 % CI -0.06 to -0.02; P < 0.001), femoral neck (WMD = -0.06; 95 % CI -0.07 to -0.04; P < 0.001), lumbar spine (WMD = -0.06; 95 % CI -0.09 to -0.03; P < 0.001), and total hip (WMD = -0.05; 95 % CI -0.06 to -0.03; P < 0.001). In addition, the meta-analysis also showed that SLE was significantly associated with increased fracture risk of all sites (relative risk [RR] = 1.97, 95 % CI 1.20-3.25; P = 0.008). Subgroup analysis by adjustment showed that SLE was significantly associated with increased fracture risk of all sites before and after adjusting for confounding factors (unadjusted RR = 2.07, 95 % CI 1.46-2.94, P < 0.001; adjusted RR = 1.22, 95 % CI 1.05-1.42, P = 0.01). Subgroup analysis by types of fracture showed that SLE was significantly associated with increased risks of hip fracture (RR = 1.99, 95 % CI 1.55-2.57; P < 0.001), osteoporotic fracture (RR = 1.36, 95 % CI 1.21-1.53; P < 0.001), and vertebral fracture (RR = 2.97, 95 % CI 1.71-5.16; P < 0.001). This systematic review and meta-analysis provides strong evidence for the relationship of SLE with bone loss and fracture risk.

Benzylation of heterocyclic N-oxides via direct oxidative cross-dehydrogenative coupling with toluene derivatives

A novel cross-dehydrogenative coupling (CDC) of heterocyclic N-oxides with toluene derivatives has been disclosed.

Neuroprotective effects of intravenous transplantation of bone marrow mononuclear cells from 5-fluorouracil pre-treated rats on ischemic stroke

Our previous findings showed bone marrow mononuclear cells (BMMNCs) from 5- fluorouracil (5-FU) pre-treated rats (named BMRMNCs) had a better therapeutic efficacy in ischemia/reperfusion rats as compared to BMMNCs from untreated rats. This study was undertaken to explore the potential mechanisms underlying the neuroprotective effects of BMRMNCs in middle cerebral artery occlusion (MCAO) rat model. Rats were intravenously pre-treated with 5-FU and BMRMNCs were collected at different time points. The contents of growth factors in the supernatant and CXCR4 expression were detected by ELISA and flow cytometry, respectively. MCAO was introduced to rats, and BMMNCs and BMRMNCs collected at 7 days after 5-FU pre-treatment were independently transplanted via the tail vein 24h later. The neurological function was evaluated before cell transplantation and at 24h, 7d and 14d after cell transplantation. Rats were sacrificed at 14d after cell transplantation, the brains were collected for TTC staining, infarct volume detection, NISSL staining, counting of viable cells in the CA1 region, and observation of transplanted cells. BMRMNCs had elevated expressions of growth factors as well as CXCR4 expression. Our results confirmed the better therapeutic effects of BMRMNCs in MCAO rats, demonstrated by reduction in infarct volume, improvement of neurological function and more viable cells in the hippocampus. In addition, more transplanted cells were found after BMRMNCs transplantation at 7 days and 14 days although there was no marked difference at 14 days. These findings indicate that BMRMNCs transplantation may protect ischemic stroke, at least partially, via increasing the secretion of growth factors and migration to the injured site.

The Statistical Modeling of Aging and Risk of Transition Project: Data Collection and Harmonization Across 11 Longitudinal Cohort Studies of Aging, Cognition, and Dementia

Longitudinal cognitive trajectories and other factors associated with mixed neuropathologies (such as Alzheimer's disease with co-occurring cerebrovascular disease) remain incompletely understood, despite being the rule and not the exception in older populations. The Statistical Modeling of Aging and Risk of Transition study (SMART) is a consortium of 11 different high-quality longitudinal studies of aging and cognition (N=11,541 participants) established for the purpose of characterizing risk and protective factors associated with subtypes of age-associated mixed neuropathologies (N=3,001 autopsies). While brain donation was not required for participation in all SMART cohorts, most achieved substantial autopsy rates (i.e., > 50%). Moreover, the studies comprising SMART have large numbers of participants who were followed from intact cognition and transitioned to cognitive impairment and dementia, as well as participants who remained cognitively intact until death. These data provide an exciting opportunity to apply sophisticated statistical methods, like Markov processes, that require large, well-characterized samples. Thus, SMART will serve as an important resource for the field of mixed dementia epidemiology and neuropathology.

Structural insights into the tumor-promoting function of the MTDH-SND1 complex

Metadherin (MTDH) and Staphylococcal nuclease domain containing 1 (SND1) are overexpressed and interact in diverse cancer types. The structural mechanism of their interaction remains unclear. Here, we determined the high-resolution crystal structure of MTDH-SND1 complex, which reveals an 11-residue MTDH peptide motif occupying an extended protein groove between two SN domains (SN1/2), with two MTDH tryptophan residues nestled into two well-defined pockets in SND1. At the opposite side of the MTDH-SND1 binding interface, SND1 possesses long protruding arms and deep surface valleys that are prone to binding with other partners. Despite the simple binding mode, interactions at both tryptophan-binding pockets are important for MTDH and SND1's roles in breast cancer and for SND1 stability under stress. Our study reveals a unique mode of interaction with SN domains that dictates cancer-promoting activity and provides a structural basis for mechanistic understanding of MTDH-SND1-mediated signaling and for exploring therapeutic targeting of this complex.

Association between the c.1564A>T genetic polymorphism of the MDR1 gene and hepatocellular carcinoma in Chinese population

The objective of this study was to evaluate the influence of c.1564A>T genetic polymorphisms in the multidrug resistance 1 gene (MDR1) on hepatocellular carcinoma (HCC) susceptibility through association analysis. A total of 632 HCC patients and 645 cancer-free controls were enrolled in this study. The c.1564A>T genetic polymorphisms were genotyped by created restriction site-polymerase chain reaction (CRS-PCR) and confirmed using DNA sequencing methods. The potential associations of c.1564A>T genetic polymorphisms with the risk of HCC were analyzed by different genetic models. Statistically significantly increased risks of HCC were detected in the homozygote comparison (TT versus AA: OR = 1.70, 95%CI = 1.17-2.45, χ(2) = 7.99, P = 0.005), recessive model (TT versus

AT/AA

OR = 1.64, 95%CI = 1.15-2.33, χ(2) = 7.66, P = 0.006), and allele contrast (T versus A: OR = 1.23, 95%CI = 1.04-1.45, χ(2) = 6.09, P = 0.014). Our data suggest that the genotypes/alleles from c.1564A>T genetic polymorphisms are statistically associated with HCC risk. The allele-T and genotype TT may contribute to susceptibility to HCC in the Chinese Han population.

Genetic ablation of metadherin inhibits autochthonous prostate cancer progression and metastasis

Metadherin (MTDH) overexpression in diverse cancer types has been linked to poor clinical outcomes, but definitive genetic proof of its contributions to cancer remains incomplete. In particular, the degree to which MTDH may contribute to malignant progression in vivo is lacking. Here, we report that MTDH is amplified frequently in human prostate cancers where its expression levels are tightly correlated with prostate cancer progression and poor disease-free survival. Furthermore, we show that genetic ablation of MTDH in the transgenic adenomcarcinoma of mouse prostate (TRAMP) transgenic mouse model of prostate cancer blocks malignant progression without causing defects in the normal development of the prostate. Germline deletion of Mtdh in TRAMP mice prolonged tumor latency, reduced tumor burden, arrested progression of prostate cancer at well-differentiated stages, and inhibited systemic metastasis to distant organs, thereby decreasing cancer-related mortality ∼10-fold. Consistent with these findings, direct silencing of Mtdh in prostate cancer cells decreased proliferation in vitro and tumor growth in vivo, supporting an epithelial cell-intrinsic role of MTDH in prostate cancer. Together, our findings establish a pivotal role for MTDH in prostate cancer progression and metastasis and define MTDH as a therapeutic target in this setting. Cancer Res; 74(18); 5336-47. ©2014 AACR.

MTDH-SND1 interaction is crucial for expansion and activity of tumor-initiating cells in diverse oncogene- and carcinogen-induced mammary tumors

The Metadherin gene (MTDH) is prevalently amplified in breast cancer and associated with poor prognosis; however, its functional contribution to tumorigenesis is poorly understood. Using mouse models representing different subtypes of breast cancer, we demonstrated that MTDH plays a critical role in mammary tumorigenesis by regulating oncogene-induced expansion and activities of tumor-initiating cells (TICs), whereas it is largely dispensable for normal development. Mechanistically, MTDH supports the survival of mammary epithelial cells under oncogenic/stress conditions by interacting with and stabilizing Staphylococcal nuclease domain-containing 1 (SND1). Silencing MTDH or SND1 individually or disrupting their interaction compromises tumorigenenic potential of TICs in vivo. This functional significance of MTDH-SND1 interaction is further supported by clinical analysis of human breast cancer samples.