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Missed Opportunities? Beneficial Uses of Illicit Drugs
Published in Ross Coomber, The Control of Drugs and Drug Users, 2020
Lester Grinspoon, James B. Bakalar
In the 1960s Walter Pahnke, a Doctor of Divinity as well as a psychiatrist, carried out an experiment designed to investigate the potential of psychedelic drugs to facilitate mystical experience (Pahnke, 1966). The study was designed as a controlled double-blind experiment. Ten seminarians from the Andover Newton Theological School took capsules containing psilocybin, while a matched control group of ten colleagues ingested a placebo just before entering the Marsh Chapel at Boston University to attend Good Friday services. Blind independent raters trained in content analysis procedures scored the descriptions of the experiences written by subjects shortly after Good Friday as well as transcripts of three separate tape-recorded interviews conducted immediately, several days and six months after the experiment. A 147-item questionnaire was administered to the subjects one or two days after Good Friday, and a 100-item questionnaire six months later.
Clinical Development Plan and Clinical Trial Design
Published in Mark Chang, John Balser, Jim Roach, Robin Bliss, Innovative Strategies, Statistical Solutions and Simulations for Modern Clinical Trials, 2019
Mark Chang, John Balser, Jim Roach, Robin Bliss
Blinding can be imposed on the investigator, the experimental subjects, the sponsor who finances the experiment, or any combination of these participants. In a single-blind experiment, the individual subjects do not know whether they have been assigned to the experimental group or the control group. Single-blind experimental design is used where the experimenters must know the treatment that the patients have been randomized to (for example, when comparing sham to real surgery). However, there is a risk that subjects are influenced by interaction with the experimenter—known as the experimenter’s bias. In double-blind experiments, both the investigator and experimental subjects have no knowledge of the group to which they are assigned. A double-blind study is usually better than a single-blind study in terms of bias reduction. In a triple-blind experiment, the patient, investigator, and sponsor are all blinded from the treatment group.
Experiments
Published in Louis Cohen, Lawrence Manion, Keith Morrison, Research Methods in Education, 2017
Louis Cohen, Lawrence Manion, Keith Morrison
In medical experiments these twin concerns are addressed by having experiments which are blind or double blind and by giving placebos to certain participants, to monitor any changes. In blind experiments, participants are not told whether they are in a control group or an experimental group, though which they are is known to the researcher. In a double-blind experiment not even the researcher knows whether a participant is in the control or experimental group; that knowledge resides with a third party. These are intended to reduce the subtle effects of participants knowing whether they are in a control or experimental group. In educational research it is easier to conduct a blind experiment than a double-blind experiment, and it is even possible not to tell participants that they are in an experiment at all, or to tell them that the experiment is about X when, in fact, it is about Y, i.e. to ‘put them off the scent’. This form of deception needs to be justified; a common justification is that it enables the experiment to be conducted under more natural conditions, without participants altering their everyday behaviour.
Direct PCR assays without DNA extraction for rapid detection of hemoglobin Constant Spring and Pakse' genes: application for carrier screening and prenatal diagnosis
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2021
Phongsathorn Wichian, Supawadee Yamsri, Attawut Chaibunruang, Cholthicha KerdKaew, Dhanawan Thongsee, Hataichanok Srivorakun, Supan Fucharoen
Ethical approval of the study protocol was approved by the Institutional Review Board of Khon Kaen University, Thailand (HE612063). Leftover whole blood and amniotic specimens were recruited from Thalassemia Service Unit (TSU), Centre for Research and Development of Medical Diagnostic Laboratories (CMDL), Faculty of Associated Medical Sciences, Khon Kaen University, Thailand. Whole blood and amniotic fluid specimens with known thalassemia genotypes were initially selected for the development of a rapid PCR assay. Additional specimens encountered (n = 290) at our routine service from November 2016 to January 2021 were used to validate the developed PCR assays. The validation was done by a blind experiment in which the operator did not know α-thalassemia genotypes of the samples before operation. Hb analysis was done using automated capillary zone electrophoresis (Capillarys, Sebia, France). Confirmation of suspected α0-thalassemia (Southeast Asian and THAI deletions) and deletional α+-thalassemia (3.7 and 4.2 kb deletions) cases were done using PCR bases techniques as described elsewhere [19–21].
Critical assessment of AI in drug discovery
Published in Expert Opinion on Drug Discovery, 2021
W. Patrick Walters, Regina Barzilay
Ultimately, evaluating the validity of any synthetic route is a non-trivial exercise. Segler and coworkers performed a blinded experiment where a group of experienced organic chemists was presented with pairs of routes for the synthesis of a set of molecules [111]. One route was taken from literature precedent and a second route was proposed by an ML method. The chemists evaluating the routes were not told the source of the syntheses and were asked to compare the routes. The chemists found the routes defined by ML to be as attractive as those reported in the literature. While such a comparison seems appealing, it is highly subjective and dependent not only on the chemists’ experience but also on the nature of the reaction products used to perform the comparison. Experimental synthesis may provide the best validation but would require expensive and labor-intensive work in the laboratory. In addition, yields will be highly dependent on the reaction conditions and catalysts employed. In practice, it can often take days to weeks for a chemist to optimize the conditions for a single reaction. As we reach a point when synthesis planning programs are coupled with a robotic apparatus for performing chemical synthesis, it may be more straightforward to evaluate the validity of reaction routes proposed by ML [118–120].
Review of galectin-3 inhibitors in the treatment of nonalcoholic steatohepatitis
Published in Expert Review of Clinical Pharmacology, 2021
Atef Al Attar, Ani Antaramian, Mazen Noureddin
In 2016, the first human clinical trial reporting on a Gal-3 inhibitor was published. GR-MD-02, also known as belpectin, was tested for its safety, pharmacokinetics, and exploratory pharmacodynamic markers in NASH patients with bridging fibrosis (F3). In this placebo-controlled, dose-ranging, and double-blind experiment, the primary outcomes were safety, tolerability, and toxicity according to dose. Secondary outcomes were dose-related pharmacokinetics, serum biomarkers, and liver stiffness scores. Three cohorts were formed to randomly receive either a placebo or GR-MD-02 at different doses (cohort 1 received 2 mg/kg n = 6, placebo n = 2; cohort 2 received 4 mg/kg n = 8, placebo n = 2; cohort 3 received 8 mg/kg n = 7, placebo n = 6). Patients were administered an initial dose and after some adjustments, received three additional doses. All doses of 2, 4, and 8 mg/kg were safe and well-tolerated, with no meaningful treatment of emergent adverse events. Vital signs, ECG recordings, and laboratory tests were found normal [50]. Due to the few data points in cohorts 1 and 2, statistical tests were not possible for fibrosis-associated biomarkers. However, cohort 3 did show a statistically significant reduction in FibroTest scores in patients treated with GR-MD-02 compared to placebo (p = 0.0055) [50].