Lanthanide-dependent RNA-cleaving DNAzymes as metal biosensors

2015 ◽  
Vol 93 (3) ◽  
pp. 273-278 ◽  
Author(s):  
Juewen Liu
Keyword(s):  
Sensor Array ◽  
Activity Patterns ◽  
Chemical Properties ◽  
Toxic Heavy Metals ◽  
Future Directions ◽  
Highly Active ◽  
Lanthanide Series ◽  
Rational Ligand Design ◽  
Heavy Lanthanides ◽  
Selection Of

Lanthanides represent a group of very important but challenging analytes for biosensor development. These 15 elements are very similar in their chemical properties. So far, limited success has been realized using the rational ligand design approach. My laboratory has successfully accomplished the task of carrying out combinatorial selection to isolate lanthanide-dependent RNA-cleaving DNAzymes. We report two new DNAzymes, each discovered in a different selection condition and both are highly specific to lanthanides. When both DNAzymes are used together, it is possible to identify the last few heavy lanthanides. Upon introducing a phosphorothioate modification, one of the abovementioned DNAzymes becomes highly active with many toxic heavy metals. With the selection of more DNAzymes with different activity patterns cross the lanthanide series, a sensor array might be produced for identifying each ion. This article is a minireview of the current developments on this topic and some of the historical aspects. It reflects the main content of the Fred Beamish Award presentation delivered at the 2014 Canadian Society for Chemistry Conference in Vancouver. Future directions in this area are also discussed.

scholarly journals Gas Sensor Array and Classifiers as a Means of Varroosis Detection

Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 117 ◽  
Author(s):  
Andrzej Szczurek ◽  
Monika Maciejewska ◽  
Beata Bąk ◽  
Jakub Wilk ◽  
Jerzy Wilde ◽  
...  
Keyword(s):  
Gas Sensor ◽  
Sensor Array ◽  
Chemical Properties ◽  
Support Vector ◽  
True Negative ◽  
Data Set ◽  
Gas Sensor Array ◽  
Efficient Detection ◽  
Bee Colonies ◽  
Selection Of

The study focused on a method of detection for bee colony infestation with the Varroa destructor mite, based on the measurements of the chemical properties of beehive air. The efficient detection of varroosis was demonstrated. This method of detection is based on a semiconductor gas sensor array and classification module. The efficiency of detection was characterized by the true positive rate (TPR) and true negative rate (TNR). Several factors influencing the performance of the method were determined. They were: (1) the number and kind of sensors, (2) the classifier, (3) the group of bee colonies, and (4) the balance of the classification data set. Gas sensor array outperformed single sensors. It should include at least four sensors. Better results of detection were attained with a support vector machine (SVM) as compared with the k-nearest neighbors (k-NN) algorithm. The selection of bee colonies was important. TPR and TNR differed by several percent for the two examined groups of colonies. The balance of the classification data was crucial. The average classification results were, for the balanced data set: TPR = 0.93 and TNR = 0.95, and for the imbalanced data set: TP = 0.95 and FP = 0.53. The selection of bee colonies and the balance of classification data set have to be controlled in order to attain high performance of the proposed detection method.

scholarly journals Insights in Behavior of Variably Formulated Alginate-Based Microcapsules for Cell Transplantation

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Pia Montanucci ◽  
Silvia Terenzi ◽  
Claudio Santi ◽  
Ilaria Pennoni ◽  
Vittorio Bini ◽  
...  
Keyword(s):  
Divalent Cations ◽  
Chemical Properties ◽  
Live Cells ◽  
High Performing ◽  
Physical Chemical ◽  
Degenerative Disorders ◽  
Selection Of ◽  
Better Than

Alginate-based microencapsulation of live cells may offer the opportunity to treat chronic and degenerative disorders. So far, a thorough assessment of physical-chemical behavior of alginate-based microbeads remains cloudy. A disputed issue is which divalent cation to choose for a high performing alginate gelling process. Having selected, in our system, high mannuronic (M) enriched alginates, we studied different gelling cations and their combinations to determine their eventual influence on physical-chemical properties of the final microcapsules preparation,in vitroandin vivo. We have shown that used of ultrapure alginate allows for high biocompatibility of the formed microcapsules, regardless of gelation agents, while use of different gelling cations is associated with corresponding variable effects on the capsules’ basic architecture, as originally reported in this work. However, only the final application which the capsules are destined to will ultimately guide the selection of the ideal, specific gelling divalent cations, since in principle there are no capsules that are better than others.

Interpreting testing and assessment: A state-of-the-art review

2021 ◽  
pp. 026553222110361
Author(s):  
Chao Han
Keyword(s):  
State Of The Art ◽  
Professional Certification ◽  
Automatic Assessment ◽  
Prospective Students ◽  
Assessment Practice ◽  
High Stakes ◽  
Future Directions ◽  
Assessment Tasks ◽  
Interpreter Education ◽  
Selection Of

Over the past decade, testing and assessing spoken-language interpreting has garnered an increasing amount of attention from stakeholders in interpreter education, professional certification, and interpreting research. This is because in these fields assessment results provide a critical evidential basis for high-stakes decisions, such as the selection of prospective students, the certification of interpreters, and the confirmation/refutation of research hypotheses. However, few reviews exist providing a comprehensive mapping of relevant practice and research. The present article therefore aims to offer a state-of-the-art review, summarizing the existing literature and discovering potential lacunae. In particular, the article first provides an overview of interpreting ability/competence and relevant research, followed by main testing and assessment practice (e.g., assessment tasks, assessment criteria, scoring methods, specificities of scoring operationalization), with a focus on operational diversity and psychometric properties. Second, the review describes a limited yet steadily growing body of empirical research that examines rater-mediated interpreting assessment, and casts light on automatic assessment as an emerging research topic. Third, the review discusses epistemological, psychometric, and practical challenges facing interpreting testers. Finally, it identifies future directions that could address the challenges arising from fast-changing pedagogical, educational, and professional landscapes.

scholarly journals The Emerging Circadian Phenotype of Borderline Personality Disorder: Mechanisms, Opportunities and Future Directions

2021 ◽  
Vol 23 (5) ◽  
Author(s):  
Niall M. McGowan ◽  
Kate E. A. Saunders
Keyword(s):  
Circadian Rhythm ◽  
Borderline Personality Disorder ◽  
Personality Disorder ◽  
Activity Patterns ◽  
Borderline Personality ◽  
Sleep Wake Disorders ◽  
Future Directions ◽  
Pilot Studies ◽  
Substantial Clinical Benefit ◽  
Biological Target

Abstract Purpose of Review We review the recent evidence suggesting that circadian rhythm disturbance is a common unaddressed feature of borderline personality disorder (BPD); amelioration of which may confer substantial clinical benefit. We assess chronobiological BPD studies from a mechanistic and translational perspective and highlight opportunities for the future development of this hypothesis. Recent Findings The emerging circadian phenotype of BPD is characterised by a preponderance of comorbid circadian rhythm sleep-wake disorders, phase delayed and misaligned rest-activity patterns and attenuated amplitudes of usually well-characterised circadian rhythms. Such disturbances may exacerbate symptom severity, and specific maladaptive personality dimensions may produce a liability towards extremes in chronotype. Pilot studies suggest intervention may be beneficial, but development is limited. Summary Endogenous and exogenous circadian rhythm disturbances appear to be common in BPD. The interface between psychiatry and chronobiology has led previously to novel efficacious strategies for the treatment of psychiatric disorders. We believe that better characterisation of the circadian phenotype in BPD will lead to a directed biological target for treatment in a condition where there is a regrettable paucity of accessible therapies.

scholarly journals Pollution Scenario due to Discharge of Effluent from Agrochemicals and Pesticides Manufacturing Industries of Dombivali Industrial Belt of Mumbai, India

2013 ◽  
Vol 22 ◽  
pp. 8-15
Author(s):  
P.U. Singare ◽  
S.S. Dhabarde
Keyword(s):  
Heavy Metals ◽  
Ph Value ◽  
Winter Season ◽  
Chemical Properties ◽  
Total Solid ◽  
Average Concentration ◽  
Summer Season ◽  
Manufacturing Industries ◽  
Toxic Heavy Metals ◽  
Physico Chemical

The paper deals with monitoring of pollution arising due to agrochemicals and pesticides manufacturing industries located along the Dombivali industrial belt of Mumbai, India. The study was carried for the period of one year from June, 2012 to May, 2013 to study the level of toxic heavy metals and the physico-chemical properties of waste water effluents discharged from the above industries. The average concentration of Cu, Ni, Cr, Pb and Zn was found to be maximum of 29.86, 0.90, 1.16 and 1.19 ppm respectively in summer season, while average Fe concentration was maximum of 51.10 ppm in winter season. The average pH value of the effluent was found to be maximum of 12.95 in summer season, while average conductivity value was maximum of 21085 µmhos/cm in rainy season. The majority of physco-chemical parameters like alkalinity, hardness, salinity, chloride, cyanide, phosphate, total solid, BOD and COD content were found to be maximum in summer season having the average values of 1918, 186, 4, 11.20, 0.07, 81, 6391, 685 and 2556 ppm respectively. The average DO content was found to be low of 4.5 ppm in winter season. It was observed that the concentration level of majority of the toxic heavy metals and physico-chemical properties were above the tolerable limit set for inland surface water. The results of present study indicates that the existing situation if mishandled can cause irreparable ecological harm in the long term well masked by short term economic prosperity due to extensive industrial growth

scholarly journals 3D Printing of Thermo-Sensitive Drugs

Pharmaceutics ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1524
Author(s):  
Sadikalmahdi Abdella ◽  
Souha H. Youssef ◽  
Franklin Afinjuomo ◽  
Yunmei Song ◽  
Paris Fouladian ◽  
...  
Keyword(s):  
3D Printing ◽  
Three Dimensional ◽  
Fused Deposition Modelling ◽  
Future Directions ◽  
Digital Light Processing ◽  
Fused Deposition ◽  
Printing Technique ◽  
3D Printed ◽  
Semi Solid ◽  
Selection Of

Three-dimensional (3D) printing is among the rapidly evolving technologies with applications in many sectors. The pharmaceutical industry is no exception, and the approval of the first 3D-printed tablet (Spiratam®) marked a revolution in the field. Several studies reported the fabrication of different dosage forms using a range of 3D printing techniques. Thermosensitive drugs compose a considerable segment of available medications in the market requiring strict temperature control during processing to ensure their efficacy and safety. Heating involved in some of the 3D printing technologies raises concerns regarding the feasibility of the techniques for printing thermolabile drugs. Studies reported that semi-solid extrusion (SSE) is the commonly used printing technique to fabricate thermosensitive drugs. Digital light processing (DLP), binder jetting (BJ), and stereolithography (SLA) can also be used for the fabrication of thermosensitive drugs as they do not involve heating elements. Nonetheless, degradation of some drugs by light source used in the techniques was reported. Interestingly, fused deposition modelling (FDM) coupled with filling techniques offered protection against thermal degradation. Concepts such as selection of low melting point polymers, adjustment of printing parameters, and coupling of more than one printing technique were exploited in printing thermosensitive drugs. This systematic review presents challenges, 3DP procedures, and future directions of 3D printing of thermo-sensitive formulations.

Parameter selection of Polystyrene-Dietilenetriaminepenta acetate Resin Synthesis for the separation of rare Earth Elements by using Plackett-Burman Experimental Design

2021 ◽  
pp. 5629-5634
Author(s):  
Herman Herman ◽  
Bohari Yusuf ◽  
Laode Rijai ◽  
Hadi Kuncoro ◽  
Anni Anggraeni ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
Chemical Properties ◽  
Ammonia Concentration ◽  
Yield Ratio ◽  
Scale Production ◽  
Separation And Purification ◽  
Diethylene Triamine ◽  
Stirring Rate ◽  
Volume Reaction ◽  
Selection Of

The development of the separation method has an essential role in developing science and technology for the separation and purification of an element or compound from other mixtures based on differences in physical and chemical properties. This research is more focused on the selection parameters of polystyrene-based resin production using diethylene triamine penta-acetate (DTPA) light, which used as a prototype for improved scale production. The Plackett-Burman design was used to select variables that have significant influence in Methylaminopolystyrene-Diethylenetriaminepentaacetate (MAP-DTPA) resin synthesis. Eleven variables such as mol ratio of Methylamino Polystyrene and diethylene triamine penta-acetate ligands, solvent volume, reaction time, stirring rate, reaction temperature, total volume, reaction pH, incubation time, ammonia concentration, and the addition of methanol were carried out for the selection of parameters or variables in the process of MAP-DTPA resin synthesis through a statistical approach in studies for design experiments using Software Design Expert 9.0.6.2. Of the eleven variables in resin synthesis obtained, six variables have a positive influence on the yield ratio value (percent yield ratio) of MAP-DTPA resin are the mol ratio of MAP and DTPA, Stirring Rate, reaction temperature, total volume, degree of acidity, and ammonia concentration.

Modeling of Selection of Relevant Cues in Rats: Effects of Task Complexity and Lesions of Medial Prefrontal Cortex

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
J. Svoboda ◽  
K. Blahna ◽  
P. Telensky ◽  
J. Bures ◽  
A. Stuchlik
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Cognitive Processing ◽  
Task Complexity ◽  
Vestibular Stimulation ◽  
Psychiatric Research ◽  
Avoidance Task ◽  
Future Directions ◽  
Place Avoidance ◽  
Selection Of

One of key features of cognitive processing in both humans and animals is to select relevant stimuli. Several rodent spatial paradigms proved to be useful in biological psychiatric research. A place avoidance task has been previously used in animal model of cognitive deficits in psychosis.Here we present modifications of the place avoidance paradigm, assessing the ability of selecting appropriate cues at various levels of task complexity. Moreover, we present a pilot experiment showing an effect of lesion to medial prefrontal cortex (mPFC) on those tasks. Generally, the place avoidance apparatus consists of a circular arena elevated 1m above the floor. Rats are trained to avoid an unmarked forbidden sector, entering which is punished by mild footshocks. The sector can be defined with respect to the room or arena frame, which can be dissociated by arena rotation. Moreover, we studied an ability of rats to avoid the place defined by salient rotating object.The results showed that animals with mPFC lesion were capable of avoiding a place defined either by distal of by proximal cues, similarly as controls. However, both control and mPFC-lesioned rats had difficulties to avoid a place surrounding moving salient object. The performance increased whenever the rat was passively rotated with the arena, suggesting that vestibular stimulation enhanced the directed attention to an object. The poster will discuss the present findings and outline the future directions with emphasis on their utilization in animal models of neuropsychiatric disorders.Supported by GACR grants 309/07/0341 and 309/06/1231.

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