Identification of the connections in biologically inspired neural networks

We developed an identification method to find the strength of the connections between neurons from their behavior in small biologically-inspired artificial neural networks. That is, given the network external inputs and the temporal firing pattern of the neurons, we can calculate a solution for the strengths of the connections between neurons and the initial neuron activations if a solution exists. The method determines directly if there is a solution to a particular neural network problem. No training of the network is required. It should be noted that this is a first pass at the solution of a difficult problem. The neuron and network models chosen are related to biology but do not contain all of its complexities, some of which we hope to add to the model in future work. A variety of new results have been obtained. First, the method has been tailored to produce connection weight matrix solutions for networks with important features of biological neural (bioneural) networks. Second, a computationally efficient method of finding a robust central solution has been developed. This later method also enables us to find the most consistent solution in the presence of noisy data. Prospects of applying our method to identify bioneural network connections are exciting because such connections are almost impossible to measure in the laboratory. Knowledge of such connections would facilitate an understanding of bioneural networks and would allow the construction of the electronic counterparts of bioneural networks on very large scale integrated (VLSI) circuits

Inhibited growth of colon cancer carcinomatosis by antibodies to vascular endothelial and epidermal growth factor receptors

Vascular endothelial growth factor (VEGF) and epidermal growth factor (EGF) regulate colon cancer growth and metastasis. Previous studies utilizing antibodies against the VEGF receptor (DC101) or EGF receptor (C225) have demonstrated independently that these agents can inhibit tumour growth and induce apoptosis in colon cancer in in vivo and in vitro systems. We hypothesized that simultaneous blockade of the VEGF and EGF receptors would enhance the therapy of colon cancer in a mouse model of peritoneal carcinomatosis. Nude mice were given intraperitoneal injection of KM12L4 human colon cancer cells to generate peritoneal metastases. Mice were then randomized into one of four treatment groups: control, anti-VEGFR (DC101), anti-EGFR (C225), or DC101 and C225. Relative to the control group, treatment with DC101 or with DC101+C225 decreased tumour vascularity, growth, proliferation, formation of ascites and increased apoptosis of both tumour cells and endothelial cells. Although C225 therapy did not change any of the above parameters, C225 combined with DC101 led to a significant decrease in tumour vascularity and increases in tumour cell and endothelial cell apoptosis (vs the DC101 group). These findings suggest that DC101 inhibits angiogenesis, endothelial cell survival, and VEGF-mediated ascites formation in a murine model of colon cancer carcinomatosis. The addition of C225 to DC101 appears to lead to a further decrease in angiogenesis and ascites formation. Combination anti-VEGF and anti-EGFR therapy may represent a novel therapeutic strategy for the management of colon peritoneal carcinomatosis. © 2001 Cancer Research Campaign http://www.bjcancer.co

Testing and extending strategies for identifying genetic disease–related encounters in pediatric patients

Purpose: To better understand health care utilization and develop decision support tools, methods for identifying patients with suspected genetic diseases (GDs) are needed. Previous studies had identified inpatient-relevant International Classification of Diseases (ICD) codes that were possibly, probably, or definitely indicative of GDs. We assessed whether these codes identified GD-related inpatient, outpatient, and emergency department encounters among pediatric patients with suspected GDs from a previous study (the North Carolina Clinical Genomic Evaluation by Next-Generation Exome Sequencing [NCGENES] study). Methods: Using the electronic medical records of 140 pediatric patients from the NCGENES study, we characterized the presence of ICD codes representing possible, probable, or definite GD-related diagnoses across encounter types. In addition, we examined codes from encounters for which initially no GD-related codes had been found and determined whether these codes were indicative of a GD. Results: Among NCGENES patients with visits between 2014 and 2017, 92% of inpatient, 75% of emergency department, and 63% of outpatient encounters included ≥1 GD-related code. Encounters with highly specific (ie, definite) GD codes had fewer low-specificity GD codes than encounters with only low-specificity GD codes. We identified an additional 32 ICD-9 and 56 ICD-10 codes possibly indicative of a GD. Conclusion: Code-based strategies can be refined to assess health care utilization among pediatric patients and may contribute to a systematic approach to identify patients with suspected GDs

Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2) Functions to Promote Uterine Decidual Angiogenesis during Early Pregnancy in the Mouse

Implantation of an embryo induces rapid proliferation and differentiation of uterine stromal cells, forming a new structure, the decidua. One salient feature of decidua formation is a marked increase in maternal angiogenesis. Vascular endothelial growth factor (VEGF)-dependent pathways are active in the ovary, uterus, and embryo, and inactivation of VEGF function in any of these structures might prevent normal pregnancy development. We hypothesized that decidual angiogenesis is regulated by VEGF acting through specific VEGF receptors (VEGFRs). To test this hypothesis, we developed a murine pregnancy model in which systemic administration of a receptor-blocking antibody would act specifically on uterine angiogenesis and not on ovarian or embryonic angiogenesis. In our model, ovarian function was replaced with exogenous progesterone, and blocking antibodies were administered prior to embryonic expression of VEGFRs. After administration of a single dose of the anti-VEGFR-2 antibody during the peri-implantation period, no embryos were detected on embryonic d 10.5. The pregnancy was disrupted because of a significant reduction in decidual angiogenesis, which under physiological conditions peaks on embryonic d 5.5 and 6.5. Inactivation of VEGFR-3 reduced angiogenesis in the primary decidual zone, whereas administration of VEGFR-1 blocking antibodies had no effect. Pregnancy was not disrupted after administration of anti-VEGFR-3 or anti-VEGFR-1 antibodies. Thus, the VEGF/VEGFR-2 pathway plays a key role in the maintenance of early pregnancy through its regulation of peri-implantation angiogenesis in the uterine decidua. This newly formed decidual vasculature serves as the first exchange apparatus for the developing embryo until the placenta becomes functionally active

Repeatability and Reproducibility of Decisions by Latent Fingerprint Examiners

The interpretation of forensic fingerprint evidence relies on the expertise of latent print examiners. We tested latent print examiners on the extent to which they reached consistent decisions. This study assessed intra-examiner repeatability by retesting 72 examiners on comparisons of latent and exemplar fingerprints, after an interval of approximately seven months; each examiner was reassigned 25 image pairs for comparison, out of total pool of 744 image pairs. We compare these repeatability results with reproducibility (inter-examiner) results derived from our previous study. Examiners repeated 89.1% of their individualization decisions, and 90.1% of their exclusion decisions; most of the changed decisions resulted in inconclusive decisions. Repeatability of comparison decisions (individualization, exclusion, inconclusive) was 90.0% for mated pairs, and 85.9% for nonmated pairs. Repeatability and reproducibility were notably lower for comparisons assessed by the examiners as “difficult” than for “easy” or “moderate” comparisons, indicating that examiners' assessments of difficulty may be useful for quality assurance. No false positive errors were repeated (n = 4); 30% of false negative errors were repeated. One percent of latent value decisions were completely reversed (no value even for exclusion vs. of value for individualization). Most of the inter- and intra-examiner variability concerned whether the examiners considered the information available to be sufficient to reach a conclusion; this variability was concentrated on specific image pairs such that repeatability and reproducibility were very high on some comparisons and very low on others. Much of the variability appears to be due to making categorical decisions in borderline cases

Analysis of gap junctional intercellular communications using a dielectrophoresis-based microchip

Gap junctions are transmembrane structures that directly connect the cytoplasm of adjacent cells, making intercellular communications possible. It has been shown that the behaviour of several tumours – such as bone tumours – is related to gap junction intercellular communications (GJIC). Several methodologies are available for studying GJIC, based on measuring different parameters that are useful for multiple applications, such as the study of carcinogenesis for example. These methods nevertheless have several limitations. The present manuscript describes the setting up of a DEP-based lab-on-a-chip platform for the real-time study of Gap Junctional Intercellular Communication between osteosarcoma cells and the main cells accessible to their microenvironment. We conclude that using the DEParray technology for the GJIC assessment has several advantages comparing to current techniques. This methodology is less harmful for cells integrity; cells can be recovered after interaction to make further molecular analysis; it is possible to study GJIC in real time; we can promote cell interactions using up to five different populations. The setting up of this new methodology overcomes several difficulties to perform experiments for solving questions about GJIC process that we are not able to do with current technics

Safety and pharmacokinetics of novel selective vascular endothelial growth factor receptor-2 inhibitor YN968D1 in patients with advanced malignancies

<p>Abstract</p> <p>Background</p> <p>YN968D1 (Apatinib) selectively inhibits phosphorylation of VEGFR-2 and tumor angiogenesis in mice model. The study was conducted to determine the maximum tolerated dose (MTD), safety profile, pharmacokinetic variables, and antitumor activity in advanced solid malignancies.</p> <p>Methods</p> <p>This dose-escalation study was conducted according to the Chinese State Food and Drug Administration (SFDA) recommendations in patients with advanced solid tumors to determine the MTD for orally administered apatinib. Doses of continuously administered apatinib were escalated from 250 mg. Treatment continued after dose-escalation phase until withdrawal of consent, intolerable toxicities, disease progression or death.</p> <p>Results</p> <p>Forty-six patients were enrolled. Hypertension and hand-foot syndrome were the two dose-limiting toxicities noted at dose level of 1000 mg. MTD was determined to be 850 mg once daily. Pharmacokinetic analysis showed early absorption with a half-life of 9 hours. The mean half-life was constant over all dose groups. Steady-state conditions analysis suggested no accumulation during 56 days of once-daily administration. The most frequently observed drug-related adverse events were hypertension (69.5%, 29 grade 1-2 and 3 grade 3-4), proteinuria (47.8%, 16 grade 1-2 and 6 grade 3-4), and hand-foot syndrome (45.6%, 15 grade 1-2 and 6 grade 3-4). Among the thirty-seven evaluable patients, PR was noted in seven patients (18.9%), SD 24 (64.9%), with a disease control rate of 83.8% at 8 weeks.</p> <p>Conclusions</p> <p>The recommended dose of 750 mg once daily was well tolerated. Encouraging antitumor activity across a broad range of malignancies warrants further evaluation in selected populations.</p> <p>Trial registration</p> <p>ClinicalTrials.gov unique identifier: NCT00633490</p

FTY720 Suppresses Liver Tumor Metastasis by Reducing the Population of Circulating Endothelial Progenitor Cells

Background: Surgical procedures such as liver resection and liver transplantation are the first-line treatments for hepatocellular carcinoma (HCC) patients. However, the high incidence of tumor recurrence and metastasis after liver surgery remains a major problem. Recent studies have shown that hepatic ischemia-reperfusion (I/R) injury and endothelial progenitor cells (EPCs) contribute to tumor growth and metastasis. We aim to investigate the mechanism of FTY720, which was originally applied as an immunomodulator, on suppression of liver tumor metastasis after liver resection and partial hepatic I/R injury. Methodology/Principal Findings: An orthotopic liver tumor model in Buffalo rat was established using the hepatocellular carcinoma cell line McA-RH7777. Two weeks after orthotopic liver tumor implantation, the rats underwent liver resection for tumor-bearing lobe and partial hepatic I/R injury. FTY720 (2 mg/kg) was administered through the inferior caval vein before and after I/R injury. Blood samples were taken at days 0, 1, 3, 7, 14, 21 and 28 for detection of circulating EPCs (CD133+CD34+). Our results showed that intrahepatic and lung metastases were significantly inhibited together with less tumor angiogenesis by FTY720 treatment. The number of circulating EPCs was also significantly decreased by FTY720 treatment from day 7 to day 28. Hepatic gene expressions of CXCL10, VEGF, CXCR3, CXCR4 induced by hepatic I/R injury were down-regulated in the treatment group. Conclusions/Significance: FTY720 suppressed liver tumor metastasis after liver resection marred by hepatic I/R injury in a rat liver tumor model by attenuating hepatic I/R injury and reducing circulating EPCs. © 2012 Li et al.published_or_final_versio