Unsupervised learning about 4D features of microparticle motion.

Material clusters of different sizes are known to exist in high-temperature plasmas due to plasma-wall interactions. The facts that these clusters, ranging from sub-microns to above mm in size, can move from one location to another quickly and that there are a lot of them make high-speed imaging and tracking one of the best, effective, and sometimes only diagnostic. An unsupervised machine learning technique based on deconvolutional neural networks is developed to analyze two-camera videos of high-temperature microparticles generated from exploding wires. The neural network utilizes a locally competitive algorithm to infer representations and optimize a dictionary composed of kernels, or basis vectors, for image analysis. Our primary goal is to use this method for feature recognition and prediction of the time-dependent three-dimensional (or "4D") microparticle motion. Features equivalent to local velocity vectors have been identified as the dictionary kernels or "building blocks" of the scene. The dictionary elements from the left and right camera views are found to be strongly correlated and satisfy the projection geometrical constraints. The results show that unsupervised machine learning techniques are promising approaches to process large sets of images for high-temperature plasmas and other scientific experiments. Machine learning techniques can be useful to handle the large amount of data and therefore aid the understanding of plasma-wall interaction.

Evaluation of digestion methods for analysis of trace metals in mammalian tissues and NIST 1577c.

Digestion techniques for ICP analysis have been poorly studied for biological samples. This report describes an optimized method for analysis of trace metals that can be used across a variety of sample types. Digestion methods were tested and optimized with the analysis of trace metals in cancerous as compared to normal tissue as the end goal. Anthropological, forensic, oncological and environmental research groups can employ this method reasonably cheaply and safely whilst still being able to compare between laboratories. We examined combined HNO3 and H2O2 digestion at 170 °C for human, porcine and bovine samples whether they are frozen, fresh or lyophilized powder. Little discrepancy is found between microwave digestion and PFA Teflon pressure vessels. The elements of interest (Cu, Zn, Fe and Ni) yielded consistently higher and more accurate values on standard reference material than samples heated to 75 °C or samples that utilized HNO3 alone. Use of H2SO4 does not improve homogeneity of the sample and lowers precision during ICP analysis. High temperature digestions (>165 °C) using a combination of HNO3 and H2O2 as outlined are proposed as a standard technique for all mammalian tissues, specifically, human tissues and yield greater than 300% higher values than samples digested at 75 °C regardless of the acid or acid combinations used. The proposed standardized technique is designed to accurately quantify potential discrepancies in metal loads between cancerous and healthy tissues and applies to numerous tissue studies requiring quick, effective and safe digestions.

Endoscopic sphenopalatine artery ligation for acute idiopathic epistaxis. Do anatomical variation and a limited evidence base raise questions regarding its place in management?

BACKGROUND: Endoscopic sphenopalatine artery ligation is widely accepted as effective and safe for acute spontaneous epistaxis that is unresponsive to conservative management. As with many new procedures, it has been progressively adopted as common practice, despite a limited evidence base for its efficacy. Early reviews called for comparative trials to support its adoption, but subsequent literature largely consists of case series and narrative reviews. These have attempted to derive an algorithm to establish its place in management, but consensus is still lacking. Intuitively, although there are theoretical objections, an operation regarded as relatively simple, fast and safe hardly seems to demand high-level evidence of efficacy. Rhinologists may be influenced by years of personal experience and success with the technique. However, estimates of the effect size and the added contribution to traditional surgical management are lacking. If the procedure could be shown to dramatically influence outcome, it should be standard practice and indispensable for all patients requiring operative intervention. OBJECTIVES: This paper systematically examined the literature, appraising the anatomical basis for such an approach and evidence for its efficacy. It questions whether any units unable to consistently offer endoscopic sphenopalatine artery ligation should be undertaking surgical management of acute epistaxis.

Design, synthesis and evaluation of marinopyrrole derivatives as selective inhibitors of Mcl-1 binding to pro-apoptotic Bim and dual Mcl-1/Bcl-xL inhibitors.

Inhibition of anti-apoptotic Mcl-1 is a promising anticancer strategy to overcome the survival and chemoresistance of a broad spectrum of human cancers. We previously reported on the identification of a natural product marinopyrrole A (1) that induces apoptosis in Mcl-1-dependent cells through Mcl-1 degradation. Here, we report the design and synthesis of novel marinopyrrole-based analogs and their evaluation as selective inhibitors of Mcl-1 as well as dual Mcl-1/Bcl-xL inhibitors. The most selective Mcl-1 antagonists were 34, 36 and 37 with 16-, 13- and 9-fold more selectivity for disrupting Mcl-1/Bim over Bcl-xL/Bim binding, respectively. Among the most potent dual inhibitors is 42 which inhibited Mcl-1/Bim and Bcl-xL/Bim binding 15-fold (IC50 = 600 nM) and 33-fold (500 nM) more potently than (±)-marinopyrrole A (1), respectively. Fluorescence quenching, NMR analysis and molecular docking indicated binding of marinopyrroles to the BH3 binding site of Mcl-1. Several marinopyrroles potently decreased Mcl-1 cellular levels and induced caspase 3 activation in human breast cancer cells. Our studies provide novel "lead" marinopyrroles for further optimization as selective Mcl-1 inhibitors and dual Mcl-1 and Bcl-xL inhibitors.

Transforming growth factor ß signaling overcomes dasatinib resistance in lung cancer.

Lung cancer is the second most common cancer and the leading cause of cancer-related deaths. Despite recent advances in the development of targeted therapies, patients with advanced disease remain incurable, mostly because metastatic non-small cell lung carcinomas (NSCLC) eventually become resistant to tyrosine kinase inhibitors (TKIs). Kinase inhibitors have the potential for target promiscuity because the kinase super family is the largest family of druggable genes that binds to a common substrate (ATP). As a result, TKIs often developed for a specific purpose have been found to act on other targets. Drug affinity chromatography has been used to show that dasatinib interacts with the TGFß type I receptor (TßR-I), a serine-threonine kinase. To determine the potential biological relevance of this association, we studied the combined effects of dasatinib and TGFß on lung cancer cell lines. We found that dasatinib treatment alone had very little effect; however, when NSCLC cell lines were treated with a combination of TGFß and dasatinib, apoptosis was induced. Combined TGFß-1 + dasatinib treatment had no effect on the activity of Smad2 or other non-canonical TGFß intracellular mediators. Interestingly, combined TGFß and dasatinib treatment resulted in a transient increase in p-Smad3 (seen after 3 hours). In addition, when NSCLC cells were treated with this combination, the pro-apoptotic protein BIM was up-regulated. Knockdown of the expression of Smad3 using Smad3 siRNA also resulted in a decrease in BIM protein, suggesting that TGFß-1 + dasatinib-induced apoptosis is mediated by Smad3 regulation of BIM. Dasatinib is only effective in killing EGFR mutant cells, which is shown in only 10% of NSCLCs. Therefore, the observation that wild-type EGFR lung cancers can be manipulated to render them sensitive to killing by dasatinib could have important implications for devising innovative and potentially more efficacious treatment strategies for this disease.

Proteasome inhibitor patents (2010 - present).

INTRODUCTION: Over the past 3 years, numerous patents and patent applications have been submitted and published involving compounds designed to inhibit the proteasome. Proteasome inhibition has been of great interest in cancer research since disruption of proteolysis leads to a significant buildup of cytotoxic proteins and activation of apoptotic pathways, particularly in rapidly proliferating cells. The current standards in proteasome inhibition are the only FDA-approved inhibitors, bortezomib and carfilzomib. Although these drugs are quite effective in treating multiple myeloma and other blood tumors, there are shortcomings, including toxicities and resistance. Most of the current patents attempt to improve on existing compounds, by increasing bioavailability and selectivity, while attempting to reduce toxicity. A general categorization of similar compounds was employed to evaluate and compare drug design strategies. AREAS COVERED: This review focuses on novel compounds and subsequent analogs developed for proteasome inhibition, used in preventing and treating human cancers. A comprehensive description and categorization of patents related to each type of compound and its derivatives, as well as their uses and efficacies as anticancer agents is included. A review of combination therapy patents has also been included. EXPERT OPINION: Although there are many diverse chemical scaffolds being published, there are few patented proteasome inhibitors whose method of inhibition is genuinely novel. Most patents utilize a destructive chemical warhead to attack the catalytic threonine residue of the proteasome active sites. Few patents try to depart from this, emphasizing the need for developing new mechanisms of action and specific targeting.

Cellular and computational studies of proteasome inhibition and apoptosis induction in human cancer cells by amino acid Schiff base-copper complexes.

Proliferation and apoptosis pathways are tightly regulated in a cell by the ubiquitin-proteasome system (UPS) and alterations in the UPS may result in cellular transformation or other pathological conditions. Indeed, the proteasome is often found to be overactive in cancer cells. It has also been found that cancer cells are more sensitive to proteasome inhibition than normal cells, and therefore proteasome inhibitors are pursued as antitumor drugs. The use of the proteasome inhibitor Bortezomib for treatment of multiple myeloma and mantle cell lymphoma has proved this principle. Recent studies have suggested that copper complexes can inhibit proteasome activity and induce apoptosis in some human cancer cells. However, the involved molecular mechanism is unknown. In this study, we investigated the biological activities of four amino acid Schiff base-copper(II) complexes by using human breast (MDA-MB-231 and MCF-7) and prostate (PC-3) cancer cells. The complexes C1 and C3, but not their counterparts C2 and C4, inhibit the chymotrypsin-like activity of purified 20S proteasome and human cancer cellular 26S proteasome, cause accumulation of proteasome target proteins Bax and IκB-α, and induce growth inhibition and apoptosis in concentration- and time-dependent manners. Docking analysis shows that C1, but not C2 has hydrophobic, pi-pi, pi-cation and hydrogen bond interactions with the proteasomal chymotrypsin-like pocket and could stably fit into the S3 region, leading to specific inhibition. Our study has identified the mechanism of action of these copper complexes on inhibiting tumor cell proteasome and suggested their great potential as novel anticancer agents.

Discovery and synthesis of hydronaphthoquinones as novel proteasome inhibitors.

Screening efforts led to the identification of PI-8182 (1), an inhibitor of the chymotrypsin-like (CT-L) activity of the proteasome. Compound 1 contains a hydronaphthoquinone pharmacophore with a thioglycolic acid side chain at position 2 and thiophene sulfonamide at position 4. An efficient synthetic route to the hydronaphthoquinone sulfonamide scaffold was developed, and compound 1 was synthesized in-house to confirm the structure and activity (IC(50) = 3.0 ± 1.6 µM [n = 25]). Novel hydronaphthoquinone derivatives of 1 were designed, synthesized, and evaluated as proteasome inhibitors. The structure-activity relationship (SAR) guided synthesis of more than 170 derivatives revealed that the thioglycolic acid side chain is required and the carboxylic acid group of this side chain is critical to the CT-L inhibitory activity of compound 1. Furthermore, replacement of the carboxylic acid with carboxylic acid isosteres such as tetrazole or triazole greatly improves potency. Compounds with a thio-tetrazole or thio-triazole side chain in position 2, where the thiophene was replaced by hydrophobic aryl moieties, were the most active compounds with up to 20-fold greater CT-L inhibition than compound 1 (compounds 15e, 15f, 15h, 15j, IC(50) values around 200 nM, and compound 29, IC(50) = 150 nM). The synthetic iterations described here not only led to improving potency in vitro but also resulted in the identification of compounds that are more active such as 39 (IC(50) = 0.44 to 1.01 µM) than 1 (IC(50) = 3.54 to 7.22 µM) at inhibiting the proteasome CT-L activity in intact breast cancer cells. Treatment with 39 also resulted in the accumulation of ubiquitinated cellular proteins and inhibition of tumor cell proliferation of breast cancer cells. The hit 1 and its analogue 39 inhibited proteasome CT-L activity irreversibly.

Shp2 protein tyrosine phosphatase inhibitor activity of estramustine phosphate and its triterpenoid analogs.

Shp2 protein tyrosine phosphate (PTP) is a novel target for anticancer drug discovery. We identified estramustine phosphate as a Shp2 PTP inhibitor from the National Cancer Institute Approved Oncology Drug set. A focused structure-activity relationship study indicated that the 17-phosphate group is required for the Shp2 PTP inhibitor activity of estramustine phosphate. A search for estramustine phosphate analogs led to identification of two triterpenoids, enoxolone, and celastrol, having Shp2 PTP inhibitor activity. With the previously reported PTP1B inhibitor trodusquemine, our study reveals steroids and triterpenoids with negatively charged phosphate, carboxylate, or sulfonate groups as novel pharmacophores of selective PTP inhibitors.

Transforming JAK1 mutations exhibit differential signalling, FERM domain requirements and growth responses to interferon-γ.

Recent work has highlighted roles for JAK (Janus kinase) family members in haemopoietic diseases. Although sequencing efforts have uncovered transforming JAK1 mutations in acute leukaemia, they have also identified non-transforming JAK1 mutations. Thus with limited knowledge of the mechanisms of JAK1 activation by mutation, sequencing may not readily identify transforming mutations. Therefore we sought to further understand the repertoire of transforming mutations of JAK1. We identified seven randomly generated transforming JAK1 mutations, including V658L and a deletion of amino acids 629-630 in the pseudokinase domain, as well as L910P, F938S, P960S, K1026E and Y1035C within the kinase domain. These mutations led to differential signalling activation, but exhibited similar transforming abilities, in BaF3 cells. Interestingly, these properties did not always correlate with JAK1 activation-loop phosphorylation. We also identified a JAK1 mutant that did not require a functional FERM (4.1/ezrin/radixin/moesin) domain for transformation. Although we isolated a mutation of JAK1 at residue Val658, which is found mutated in acute leukaemia patients, most of the mutations we identified are within the kinase domain and have yet to be identified in patients. Interestingly, compared with cells expressing JAK1-V658F, cells expressing these mutants had higher STAT1 (signal transducer and activator of transcription 1) phosphorylation and were more sensitive to interferon-γ-mediated growth inhibition. The differential STAT1 activation and interferon-sensitivity of JAK1 mutants may contribute to the determination of which specific JAK1 mutations ultimately contribute to disease and thus are identified in patients. Our characterization of these novel mutations contributes to a better understanding of mutational activation of JAK1.

The ubiquitin-proteasome system and assays to determine responses to inhibitors.

IMPORTANCE OF THE FIELD: Proteasome inhibition is an important therapeutic modality. Additionally, given the toxicities of direct proteasome inhibition, interest is increasing in modulating the ubiquitin ligases in the ubiquitin-proteasome system (UPS). AREAS COVERED IN THIS REVIEW: A detailed examination of the ubiquitin-proteasome pathway and an examination of methods of inhibiting this pathway from a variety of targets including the proteasome, the ubiquitin ligases and molecular biology techniques. Special attention is given to the assays used to measure modulation of the ubiquitin-proteasome pathway. WHAT THE READER WILL GAIN: A thorough examination of the UPS and its role in cells and disease and an overview of several assays for analyzing the effect of inhibitors on the UPS. Significant detail is given to assays of the ligase system and molecular approaches. These assays have their own advantages and disadvantages and will allow investigators to make informed choices on investigating the UPS. TAKE HOME MESSAGE: Interrupting the UPS can have profound consequences for cellular health and disease progression. The ubiquitin-proteasome pathway contains multiple activities that cannot be definitively assayed by a single technique. Assaying the UPS requires investigators to use multiple corroborating techniques and avoid confounding issues within each technique.

Otological and vestibular symptoms in patients with low grade (Quebec grades one and two) whiplash injury.

OBJECTIVE: To establish the prevalence of new vestibular and otological symptoms in a group of patients who had sustained a low grade (Quebec grades one or two) whiplash injury. METHODS: A retrospective review of the case records of 109 patients undergoing assessment by a single practitioner for the purposes of compiling a medicolegal report on their whiplash injury. RESULTS: Four patients complained of short-lived, non-specific dizziness symptoms in the acute phase following their original injury. There were no reports of vertigo, tinnitus or hearing loss after a mean period of 149 days following the whiplash injury. CONCLUSIONS: No patients reported otological or persistent vestibular symptoms in the acute phase following their whiplash injury. This suggests that caution should be exercised when attributing these symptoms to such an injury. Before whiplash injuries are admitted as an aetiological factor in the development of such symptoms, other causes should be excluded.

Use of an optical surface scanner in assessment of outcome following rhinoplasty surgery.

OBJECTIVE: To demonstrate the use of an optical surface scanner, with associated software, in the assessment of rhinoplasty patients, and to discuss the possible clinical applications of this technology in the future. DESIGN: Case study analysis of pre- and post-operative scans of a patient undergoing septorhinoplasty at Whipps Cross University Hospital, London, UK. SUBJECT: A 21-year-old man undergoing septorhinoplasty underwent pre-operative optical surface scanning of his face. The scans were repeated at one week and one year post-operatively. Software developed at University College London was then used to analyse the scans. RESULTS: The scans clearly showed that the man's dorsal hump had been well reduced and the nose straightened, with a resulting 1600 mm3 gain on the right side and a 1000 mm3 loss on the left side of the nose. Tip projection had also been achieved. CONCLUSION: This technique allowed objective quantification of facial features and analysis of change. It may well prove useful in the future in predicting change following surgical intervention.

Computational validation of the importance of absolute stereochemistry in virtual screening.

Consideration of stereochemistry early in the identification and optimization of lead compounds can improve the efficiency and efficacy of the drug discovery process and reduce the time spent on subsequent drug development. These improvements can result by focusing on specific enantiomers that have the desired potential therapeutic effect (eutomers), while removing from consideration enantiomers that may have no, or even undesirable, effects (distomers). A virtual screening campaign that correctly takes stereochemical information into account can, in theory, be utilized to provide information about the relative binding affinities of enantiomers. Thus, the proper enumeration of the relevant stereoisomers in general, and enantiomeric pairs in particular, of chiral compounds is crucial if one is to use virtual screening as an effective drug discovery tool. As is obvious, in cases where no stereochemical information is provided for chiral compounds in a 2D chemical database, then each possible stereoisomer should be generated for construction of the subsequent 3D database to be used for virtual screening. However, acute problems can arise in 3D database construction when relative stereochemistry is encoded in a 2D database for a chiral compound containing multiple stereogenic atoms but absolute stereochemistry is not implied. In this case, we report that generation of enantiomeric pairs is imperative in database development if one is to obtain accurate docking results. A study is described on the impact of the neglect of enantiomeric pairs on virtual screening using the human homolog of murine double minute 2 (MDM2) protein, the product of a proto-oncogene, as the target. Docking in MDM2 with GLIDE 4.0 was performed using the NCI Diversity Set 3D database and, for comparison, a set of enantiomers we created corresponding to mirror image structures of the single enantiomers of chiral compounds present in the NCI Diversity Set. Our results demonstrate that potential lead candidates may be overlooked when databases contain 3D structures representing only a single enantiomer of racemic chiral compounds.

In silico chemical library screening and experimental validation of a novel 9-aminoacridine based lead-inhibitor of human S-adenosylmethionine decarboxylase.

In silico chemical library screening (virtual screening) was used to identify a novel lead compound capable of inhibiting S-adenosylmethionine decarboxylase (AdoMetDC). AdoMetDC is intimately involved in the biosynthesis of polyamines, which are essential for tumor progression and are elevated in numerous types of tumors. Therefore, inhibition of this enzyme provides an attractive target for the discovery of novel anticancer drugs. We performed virtual screening using a computer model derived from the X-ray crystal structure of human AdoMetDC and the National Cancer Institute's Diversity Set (1990 compounds). Our docking study suggested several compounds that could serve as drug candidates since their docking modes and scores revealed potential inhibitory activity toward AdoMetDC. Experimental testing of the top-scoring compounds indicated that one of these compounds (NSC 354961) possesses an IC50 in the low micromolar range. A search of the entire NCI compound collection for compounds similar to NSC 354961 yielded two additional compounds that exhibited activity in the experimental assay but with significantly diminished potency relative to NSC 354961. In this report, we disclose the activity of NSC 354961 against AdoMetDC and its probable binding mode based on computational modeling. We also discuss the importance of virtual screening in the context of enzymes that are not readily amenable to high-throughput assays, thereby demonstrating the efficacy of virtual screening, combined with selective experimental testing, in identifying new potential drug candidates.

Bi-lobar post-auricular skin flap for reconstruction of the earlobe.

INTRODUCTION: Ear lobule deformities can occur as a result of trauma. Surgical reconstruction can be challenging. There does not appear to be a consensus on the best form of repair. We report the case of a 27-year-old woman who suffered traumatic loss of the ear lobule during childhood. A novel technique is described using a posterior based bi-lobar flap to completely reconstruct the ear lobule in two stages. DISCUSSION: This form of repair has the advantage of a well-hidden scar, with the donor site providing skin of similar thickness and pigmentation.

Rhythmic auditory stimulation improves gait more than NDT/Bobath training in near-ambulatory patients early poststroke: a single-blind, randomized trial.

OBJECTIVES: The effectiveness of 2 different types of gait training in stroke rehabilitation, rhythmic auditory stimulation (RAS) versus neurodevelopmental therapy (NDT)/Bobath- based training, was compared in 2 groups of hemiparetic stroke patients over a 3-week period of daily training (RAS group, n = 43; NDT/Bobath group =35). METHODS: Mean entry date into the study was 21.3 days poststroke for the RAS group and 22.3 days for the control group. Patients entered the study as soon as they were able to complete 5 stride cycles with handheld assistance. Patients were closely equated by age, gender, and lesion site. Motor function in both groups was pre-assessed by the Barthel Index and the Fugl-Meyer Scales. RESULTS: Pre- to posttest measures showed a significant improvement in the RAS group for velocity (P = .006), stride length (P = .0001), cadence (P = .0001) and symmetry (P = .0049) over the NDT/Bobath group. Effect sizes for RAS over NDT/Bobath training were 13.1 m/min for velocity, 0.18 m for stride length, and 19 steps/min for cadence. CONCLUSIONS: The data show that after 3 weeks of gait training, RAS is an effective therapeutic method to enhance gait training in hemiparetic stroke rehabilitation. Gains were significantly higher for RAS compared to NDT/Bobath training.

The maturation of balance in children.

BACKGROUND: Balance function is known to change with age during infancy and childhood. However, the relative contributions of the three primary inputs to position sense are not fully understood. METHODS: In this paper we report the computerised dynamic posturography findings in a group of 60 healthy children from the age of five to 17. RESULTS: The results confirm that there is a progressive improvement in balance function with age. The EquiTest system that was used gave indications of the relative contributions of the three principal contributors to overall balance function and showed that somatosensory function was intact throughout the age range tested and that there are significant increases in vestibular function with age and visual contribution with height. The technique used was found to be reliable and repeatable in this paediatric sample. CONCLUSIONS: It is hoped that a better understanding of the normal age related development of balance will be helpful in dealing with children presenting with disequilibrium and vertigo.