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A new polycrystalline form of hydroxylapatite, CHA, has been shown to closely mimic dental enamel, in vitro, in regard to rate and degree of plaque formation and effectiveness of antiplaque drugs. The material has successfully been exploited as a standardized hydroxylapatite plaque growth substrate in conjuntion with a mass antidental plaque drug screening program.
Respirophonography is an objective method of measuring respiratory and adventicious sounds. Current techniques make a perfect, albeit somewhat tedious registering of these respiratory murmurs possible, which can then be analysed for frequency. In this paper the method is investigated for its applicability to drug screening and proved satisfactory in a double blind trial and a pilot study. During treatment with secretolytic drugs the pathological respiratory sounds change or cease. In the respirophonogram this is recognisable by the fact that the volume peaks are either displaced to another frequency area or that they disappear altogether. The frequency range 100--500 Hz is the most significant as far as the respiratory murmurs are concerned. The concepts familiar to the clinician experienced in auscultation are set out in an unaccustomed way in the frequency-volume diagram. The respirophonogram offers the advantage that it can be documented and that findings can therefore be compared objectively. From the point of view of the clinician respirophonography is despite its far reaching perfection already attained, still technically in a preliminary stage.
Urine samples (n = 300) were examined for drugs by thin-layer chromatography ("Drug Skreen", Brinkmann Corp.) and by the "Enzyme Multiplied Immunoassay Technique" ("Emit", Syav Corp.). The results of both methods were compared for the detection of opiates, barbiturates and amphetamines. In more than 90% of the determinations identical results were obtained with both methods. About 10% of the results of the Emit barbiturate assay differed from those of thin-layer chromatography and therefore had to be further investigated by gas liquid chromatography. It could be demonstrated that the barbiturate determination by the Emit system correlated better with the results of gas liquid chromatography. From the results of this study it is suggested that thin-layer chromatography is used as a screening test, and to confirm positive results with other methods such as Emit. If the abuse of barbiturates or opiates is suspected the corresponding Emit test should also be performed, even in cases of a negative thin-layer chromatography screening. Confirmation with a third method such as gas liquid chromatography is necessary, if thin-layer chromatography and Emit lead to divergent results.
The Freund's adjuvant technic, using killed Mycobacterium butyricum suspended in mineral oil, is a refined tool for anti-inflammatory drug evaluation. Its use has long been reserved for testing and not for screening due to technical problems in the preparation of valid animal models. After reviewing the methodology, the authors demonstrated that the availability of arthritic rats from a modern breeding center (Charles River France, SA, Elbeuf, France) make the procedure applicable to drug screening. This has both practical and economic advantages. The animals can be used as test organisms for drug evaluation 14 da after treatment. Three criteria for measuring the effectiveness of anti-arthritic drugs have been established: an arithritic index determined by examination of the 4 paws; changes in the erythrocyte sedimentation rate; and changes in levels of plasma fibrinogen. The curative activity of test substances can be evaluated by a single series of measurements of these 3 criteria after 14 da of treatment. This test was compared with 2 others; edema of the paw induced by the subcutaneous injection of kaolin or carrageenan, and was found to be superior.
A biological test system has been developed to assess the prophylactic activity of compounds against sporozoite-induced Plasmodium berghei malaria in mice. The procedure was designed to serve as the foundation of an effort to develop tissue schizonticidal drugs in a manner parallel to that of a previous system employed in the U.S. Arym Antimalarial Drug Development Program to screen compounds for blood schizonticidal activity. In tests with 35 known antimalarial compounds, the new screen was found to be in agreement 93% and 80%, respectively, when assessed compound activity was compared with results obtained in a definitive mouse causal prophylactic test and a rhesus monkey radical curative system.
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Coxsackievirus B4 (CVB4) is an enterovirus with one of the highest mortality rates following infection, yet research on it remains limited. To enhance the efficiency of CVB4 research, we developed the rCVB4-EGFP and rCVB4-NanoLuc reporter viruses. The replication kinetics of these reporter viruses in SH-SY5Y and HeLa cells were essentially consistent with those of the wild-type CVB4. A strong correlation was observed between the fluorescence and bioluminescence signals of rCVB4-EGFP and rCVB4-NanoLuc and viral titers at specific times postinfection. When evaluating the anti-CVB4 drug fluoxetine using these reporter viruses, the half-maximal effective concentrations derived from fluorescence signals, bioluminescence signal intensities, and viral genome copies were consistent. In In Vivo drug evaluations, because CVB4 can infect various tissues and organs, the bioluminescence signal of rCVB4-NanoLuc effectively demonstrated the antiviral effects of drugs, offering significant advantages over traditional tissue viral titer analysis. The reporter viruses exhibited reduced virulence compared with wild-type CVB4 both In Vitro, in SH-SY5Y and HeLa cells, and In Vivo, in ICR suckling mice. Although this reduced virulence may limit their application for studying pathogenic mechanisms, these reporter viruses can serve as highly efficient tools for high-throughput screening and evaluation of anti-CVB4 drugs, vaccines, and neutralizing antibodies.
The methods for barbiturate, opiate, methadone, and amphetamine have been modified for use with the American Monitor KDA. The modification, which incorporates automatic correction for endogenous lysozyme activity, was evaluated by comparing results obtained with the KDA for human urine samples containing known amounts of drug(s) with results obtained with the procedure recommended by Syva for the Gilford 3500. There was 98% agreement bewteen the two systems. Six calibrators and 40 samples can be assayed for all four drugs in about 2.5 h. The procedure has proven to be reliable for screening urine samples obtained from clients at a methadone treatment center.
The intradermal injection of certain drugs with antimitotic properties in the guinea pig resulted in localized areas of reversible hair loss or hair growth inhibition. The size of the affected field was related to the dose. This may provide a useful and simple method for the rapid screening of potentially useful agents for local cytostatic activity.
Cardiac fibrosis, characterized by aberrant fibroblast activation and excessive extracellular matrix deposition, lacks target-specific therapies, largely due to the absence of longitudinal, scalable, and non-destructive in vitro screening platforms. Traditional end-point assays and resource-intensive stem cell models inherently preclude real-time monitoring of fibrotic progression. To overcome these limitations, this protocol describes the generation, optimization, and validation of a mouse collagen type I alpha 1 (Col1a1) promoter-driven adenoviral mCherry fluorescent reporter system (Ad-mCol1a1p-mCherry) in NIH/3T3 fibroblasts. The critical steps for recombinant adenovirus packaging, transduction optimization (multiplicity of infection) to minimize cytotoxicity, and the establishment of a robust transforming growth factor beta (TGF-β)-induced fibrosis model are detailed. By circumventing the need for cell fixation, this system enables direct and longitudinal monitoring of collagen transcription in live cells. The model's specificity and reliability are pharmacologically validated using the TGF‑β type I receptor (ALK5) inhibitor SB431542, with fluorescent readouts correlating with endogenous fibrotic markers quantified via reverse transcription quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. Ultimately, this cost-effective platform provides an accessible tool for the high-throughput screening of novel antifibrotic agents, thereby accelerating translational cardiovascular research.
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Morphine and methamphetamine, which are excreted in the sweat, are detected by the use of routine serological and physicochemical techniques for urinary examinations. Screening for drug abuse can be done with the same accuracy of that of urine. Rapid excretion of the drug via kidney (within one day) is followed by a slow but steady excretion of the sweat gland. Methamphetamine given orally in a dose of 10 mg is excreted in the sweat at a constant rate (1.4 microgram/ml). No significant difference of the amount excreted by both systems is found. Alveolar lining seems to prevent the elimination of the volatile methamphetamine via respiration. Not only narcotics and stimulants, but also many alkaloids and barbituarates are excreted in the sweat and detected quantitatively by the same principles. The toxicological analysis of the sweat promises a new scope of forensic investigation.
The effects of hallucinogenic and nonhallucinogenic drugs were studied on two behavioral tests: (1) discriminated Sidman avoidance, using modified Bovet-Gatti profiles, which have been proposed as specific in detecting hallucinogenic activity and (2) a drug discrimination experiment. By the first method, the "hallucinogenic profile" was obtained with both hallucinogenic and nonhallucinogenic drugs and, at least as used here, was not a suitable screening method. In the drug discrimination experiment, data from the present study along with other available evidence suggest the potential value of this method for drug screening procedures.
Coronaviruses (CoVs) pose a significant threat to human health, as demonstrated by the COVID-19 pandemic. The large size of the CoV genome (around 30 kb) represents a major obstacle to the development of reverse genetics systems, which are invaluable for basic research and antiviral drug screening. In this study, we established a rapid and convenient method for generating reverse genetic systems for various CoVs using a bacterial artificial chromosome (BAC) vector and Gibson DNA assembly. Using this system, we constructed infectious cDNA clones of coronaviruses from three genera: human coronavirus 229E (HCoV-229E) of the genus Alphacoronavirus, mouse hepatitis virus A59 (MHV-59) of Betacoronavirus, and porcine deltacoronavirus (PDCoV-Haiti) of Deltacoronavirus. Since beta coronaviruses including severe acute respiratory syndrome coronavirus (SARS-CoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and Middle East respiratory syndrome coronavirus (MERS-CoV) represent major human pathogens, we modified the infectious clone of the beta coronavirus MHV-A59 by replacing its NS5a gene with a fluorescent reporter gene to create a system suitable for high-throughput drug screening. Thus, this study provides a practical and cost-effective approach to developing reverse genetics platforms for CoV research and antiviral drug screening.
Phenotypic screens carried out with functional genomics or small molecules have led to novel biological insights, revealed previously unknown targets for drug discovery programs, and provided starting points for the development of first-in-class therapies. Despite being valuable research tools, genetic and compound screening also have significant limitations. This perspective aims to shed a light on those limitations and provide mitigation strategies when available, with a goal of helping phenotypic screening practitioners gain an understanding of how and when to best utilize either approach.
BACKGROUND: Colorectal cancer (CRC) remains a leading cause of global cancer mortality, highlighting the need for precise survival prediction to guide clinical decisions. Although tissue-level multi-omics is widely utilized for survival prediction, its limited resolution cannot capture tumor heterogeneity. Single-cell RNA sequencing (scRNA-seq) enables dissection of the tumor microenvironment (TME) at cellular resolution, supporting personalized prognostic assessment. METHODS: We collected 213 CRC scRNA-seq samples and established a CRC-specific TME atlas comprising 339,060 cells. Using this atlas as a reference, we deconvolved bulk RNA-seq data from TCGA-CRC cohort with the EcoTyper algorithm to reconstruct TME features. Clinical, genomic, and transcriptomic data were obtained from the Xena platform; microbial data were sourced from the BIC database. We integrated TME and multi-omics features through a self-normalizing neural network to construct a deep learning model (single-cell resolution TME ecosystem with multi-omics data [SCMO]) for survival prediction. To enhance interpretability, we utilized the Integrated Gradients algorithm and spatial transcriptomic data to analyze multi-omics and TME features. We performed anticancer drug screening with tumor necrosis factor receptor-associated protein 1 (TRAP1), a critical feature according to the Integrated Gradients algorithm, as a potential target. RESULTS: We identified 13 survival-related TME features from the CRC-specific atlas: 12 cell states and one multi-cellular ecosystem. SCMO, which combined TME and multi-omics features, improved survival prediction and outperformed existing methods, achieving a concordance index of 0.762. The SCMO demonstrated robust performance for long-term predictions, achieving areas under the curve (AUCs) of 0.752, 0.772, and 0.869 for 1-, 3-, and 5-year predictions in the training set, with corresponding test set AUCs of 0.639, 0.756, and 0.772. TME features from the SCMO model revealed that ecosystem density increased with CRC malignancy. Multi-omics features included TRAP1 as a potential drug target. Drug screening identified saikosaponin A as a novel TRAP1 inhibitor, and its anticancer activity was validated in vitro. We developed SCMO-Lite, a simplified model incorporating 12 high-attribution-weight multi-omics features, which demonstrated robust risk stratification. CONCLUSIONS: SCMO combines analytical precision with biological interpretability, offering novel insights for oncology survival prediction.
BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration is used for clinical diagnosis and staging in patients with lung cancer. Nevertheless, establishing patient-derived preclinical models using needle biopsy samples remains challenging. This study describes the establishment and utility of patient-derived organoid (PDO) from endobronchial ultrasound-guided (EBUS) specimens and EBUS patient-derived xenograft (PDX). METHODS: A total of 175 EBUS specimens were used to establish PDO and PDX. "Stable establishment" organoids with passage numbers of 10 or greater were used for genomic, transcriptome, and pathologic assessment. Drug sensitivity of EBUS organoids and PDX tumors were compared with those of the matched patient. Drug screening was performed using stably established organoid models. RESULTS: We successfully established a total of 20 EBUS organoids: six EBUS-PDOs and 14 EBUS-xenograft derived organoids. These stable cancer organoid models were validated for cancer cell enrichment and pathologic assessment. Pathologic findings, exome, and transcriptome analysis found a high correlation between EBUS organoids and parental samples. EBUS organoids and PDX indicated consistent drug response patterns with their corresponding patients. A drug screening conducted on an EBUS organoid led to the discovery of potent activity of trametinib to a rare MAP2K1 K57N mutation. CONCLUSIONS: EBUS-PDO and -xenograft‒derived organoids are good options to generate stable organoids in patients with advanced stage lung cancer. The models were consistent with the genetic and pathologic features of patient tumors, and the patient's responses to treatment, supporting their utility for novel therapeutic research.
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