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Discover the most talked about and latest scientific content & concepts.

Concept: Laboratory

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The systematic measurement of luminance thresholds during dark adaptation usually requires advanced optical equipment not available in most undergraduate classes. Here we describe an easy, inexpensive alternative that uses a printed grayscale to measure visual thresholds. Adaptation curves found with this method are comparable to those found with the technologically advanced tools in the standard literature and even show the shift from cone to rod vision at around 4-8 minutes. The exercise can furthermore be easily combined with a demonstration of the Purkinje shift (the different spectral sensitivity of the rod and cone systems) and of multi-sensory integration across vision, touch and proprioception. The lab allows students to collect, graph and analyze both qualitative and quantitative data. Student ratings of the activity are highly positive, even when compared to other visual neuroscience labs. The activity provides an effective and accessible tool for teaching several important neuroscience concepts, including retinal circuitry, spectral sensitivity, and multi-sensory integration.

Concepts: Retina, Eye, Visual perception, Qualitative research, Laboratory, Rod cell, Scotopic vision, Purkinje effect

118

Unmanned Aerial Systems (UAS or drones) could potentially be used for the routine transport of small goods such as diagnostic clinical laboratory specimens. To the best of our knowledge, there is no published study of the impact of UAS transportation on laboratory tests.

Concepts: Medicine, Chemistry, Experiment, Greatest hits albums, Laboratory, Helicopter

69

The pharmaceutical and biotechnology industries depend on findings from academic investigators prior to initiating programs to develop new diagnostic and therapeutic agents to benefit cancer patients. The success of these programs depends on the validity of published findings. This validity, represented by the reproducibility of published findings, has come into question recently as investigators from companies have raised the issue of poor reproducibility of published results from academic laboratories. Furthermore, retraction rates in high impact journals are climbing.

Concepts: Medicine, University, Laboratory, Impact factor, Depend

53

PurposeThere is increasing demand from the public for direct-to-consumer (DTC) genetic tests, and the US Food and Drug Administration limits the type of health-related claims DTC tests can market. Some DTC companies provide raw genotyping data to customers if requested, and these raw data may include variants occurring in genes recommended by the American College of Medical Genetics and Genomics to be reported as incidental/secondary findings. The purpose of this study was to review the outcome of requests for clinical confirmation of DTC results that were received by our laboratory and to analyze variant classification concordance.MethodsWe identified 49 patient samples received for further testing that had previously identified genetic variants reported in DTC raw data. For each case identified, information pertaining to the outcome of clinical confirmation testing as well as classification of the DTC variant was collected and analyzed.ResultsOur analyses indicated that 40% of variants in a variety of genes reported in DTC raw data were false positives. In addition, some variants designated with the “increased risk” classification in DTC raw data or by a third-party interpretation service were classified as benign at Ambry Genetics as well as several other clinical laboratories, and are noted to be common variants in publicly available population frequency databases.ConclusionOur results demonstrate the importance of confirming DTC raw data variants in a clinical laboratory that is well versed in both complex variant detection and classification.GENETICS in MEDICINE advance online publication, 22 March 2018; doi:10.1038/gim.2018.38.

Concepts: DNA, Medicine, Gene, Genetics, Biology, Genome, Genomics, Laboratory

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Experimental research has become complex and thus a challenge to science education. Only very few students can typically be trained on advanced scientific equipment. It is therefore important to find new tools that allow all students to acquire laboratory skills individually and independent of where they are located. In a design-based research process we have investigated the feasibility of using a virtual laboratory as a photo-realistic and scientifically valid representation of advanced scientific infrastructure to teach modern experimental science, here, molecular quantum optics. We found a concept based on three educational principles that allows undergraduate students to become acquainted with procedures and concepts of a modern research field. We find a significant increase in student understanding using our Simulated Interactive Research Experiment (SiReX), by evaluating the learning outcomes with semi-structured interviews in a pre/post design. This suggests that this concept of an educational tool can be generalized to disseminate findings in other fields.

Concepts: Causality, Education, Chemistry, Science, Research, Experiment, Theory, Laboratory

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Purpose:Single-nucleotide polymorphism (SNP) microarrays are capable of detecting regions of homozygosity (ROH) that can suggest parental consanguinity or incest. This study was designed to describe the variable reporting practices of clinical laboratories in the United States regarding ROH found on SNP microarray tests, to discuss the follow-up practices of laboratory personnel when findings of ROH indicate consanguinity or incest, and to highlight the legal and ethical dilemmas faced by workers who have discovered these incidental findings.Methods:A 20-question survey was administered to microarray experts at 18 laboratories offering clinical SNP microarray tests. The results are presented using descriptive statistics.Results:There was variability in laboratory SNP microarray reporting practices with respect to information and interpretation of ROH findings. All the laboratories agreed that they have a duty to inform the ordering physician about results suggesting consanguinity or incest, but the follow-through practices varied among laboratories.Conclusions:This study discovered variability in reporting practices and follow-up procedures for microarray results that suggest parental consanguinity or incest. Our findings highlight the need for laboratory guidelines to standardize reporting practices for SNP microarray and other tests that are capable of detecting ROH.Genet Med 2012:14(12):971-976.

Concepts: Marriage, United States, Laboratory, Microarray, Microarrays, Variable, Consanguinity, Incest

28

We aim in this study to provide levels of susceptibility of 162 bloodstream isolates of non-Candida albicans and non-C. tropicalis species from a sentinel program conducted in 11 hospitals in Brazil. Additionally, we compared the broth microdilution (BMD) method of the European Committee of Susceptibility Testing (EUCAST) with Clinical Laboratory Standards Institute (CLSI) BMD method for fluconazole, itraconazole, voriconazole, and amphotericin B. The study included 103 C. parapsilosis, 38 C. glabrata, 8 C. orthopsilosis, and 7 C. krusei isolates, and single isolates of Pichia anomala, C. famata, C. lusitaniae, C. kefyr, C. guilliermondii, and C. metapsilosis. Of note, we observed cross-resistance between fluconazole and voriconazole for two isolates being one C. parapsilosis and one C. glabrata. Good essential agreement (EA) was observed between the EUCAST and the CLSI results for C. parapsilosis and for fluconazole, itraconazole, voriconazole, and amphotericin B, respectively: 98%, 99%, 98%, and 97%. Otherwise, for C. glabrata, the EA for fluconazole was 84.2% and for voriconazole 89.4%. Because data from Brazil are scarce, our results contribute to the consolidation of the database of candidemia agents and monitoring of trends in the profile of drug resistance.

Concepts: Laboratory, Amphotericin B, The Europeans, Antifungals, Candidiasis, Ergosterol, Triazole, World Health Organization essential medicines

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This work examines the synthesis of 3,4-methylenedioxy-N-methylamphetamine (MDMA) from common starting materials that may be utilised by clandestine laboratory operators. Piperonal was prepared from two common starting materials, piperine (from pepper) and vanillin (a common flavouring). Piperine was converted to piperonal by ozonolysis and oxidative cleavage with potassium permanganate and tetrahydrofuran. Vanillin was converted to piperonal by demethylation with pyridine and aluminium chloride followed by methylenation with dichloromethane. The resulting piperonal samples were converted via a commonly encountered route to MDMA. The impurities that indicate a particular route were identified and the feasibility of each method was also assessed.

Concepts: Redox, Aluminium, Laboratory, Methamphetamine, MDMA, Potassium permanganate, Manganese, Black pepper

28

We report a rare task-specific dystonia(1,2) in a 26-year-old man with a 4-year progressive speech disorder characterized by oromandibular spasms. Family and medical history were unremarkable; he was never exposed to neuroleptic drugs or toxic agents. Neurologic examination revealed only speech-induced oromandibular dystonic movements, characterized by forced jaw opening, interfering with speech (video on the Neurology(®) Web site at www.neurology.org). However, he was able to sing and to perform other voluntary activities (swallowing, drinking, chewing). Laboratory tests and brain magnetic resonance scans were normal. He received a placebo injection with no benefit. Trihexyphenidyl was started with moderate benefit. This rare form of dystonia is sometimes triggered by praying,(1,2) resembling task-specific occupational dystonias.

Concepts: Medicine, Brain, Neurology, Dystonia, Singing, Laboratory, Oromandibular dystonia, Tardive dyskinesia

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This article concerns the analysis of the Adverse Analytical Findings (AAFs) and the appropriate alterations made during the period 2005-2011, so that the Doping Control Laboratory of Athens (DCLA) obeys the updated World Anti-Doping Agency (WADA) List of Prohibited Substances. The % AAFs of the DCLA was compared with those of WADA-Accredited Laboratories. In 2008, the term Atypical Finding was introduced by the WADA representing a reported but inconclusive result. A characteristic example is when a testosterone-to-epitestosterone ratio is >4 followed by a negative gas chromatography/combustion/isotope ratio mass spectrometry result. In a total of about 30,000 athlete samples, 136 athletes were found with an increased testosterone/epitestosterone ratio and 43 with tetrahydrocannabinol metabolite (THCCOOH) of 427 reported AAFs. Twenty-one athletes in total were found positive with methylhexaneamine, the 11 found after a batch of 1000 samples was reprocessed. Besides, there were AAFs below their Minimum Required Performance Level (MRPL). The increasing need for higher detectability imposed new apparatus, e.g., liquid chromatography/quadrupole/time-of-flight mass spectrometry, whereas that for lowering the capital costs and reporting times led to the unification of the screening method which includes stimulants, diuretics, anabolics and other substances.

Concepts: Mass spectrometry, Report, Control theory, Laboratory, Finding, Earwire, World Anti-Doping Agency, The Capital