Laboratory Work Research Articles

Organisation of the Work of Bioanalytical Laboratories according to the Principles of Good Clinical Laboratory Practice (Review)

INTRODUCTION. Bioanalytical laboratories in the Russian Federation should follow the requirements of both the Good Laboratory Practices (GLP), when performing tests for non-clinical studies, and the Good Clinical Practices (GCP), when analysing samples from clinical studies. The work of such laboratories requires a separate GxP system, the Good Clinical Laboratory Practices (GCLP). However, the GCLP system has not yet been created in the Russian Federation and the Eurasian Economic Union (EAEU).АIM. This study aimed to compare the current Russian and EAEU principles regulating the work of bioanalytical laboratories with the international GCLP principles and formulate general requirements for national laboratories.DISCUSSION. The author analysed the current regulation of the work of bioanalytical laboratories, as well as the EAEU regulatory standards for the development and validation of analytical procedures. In addition, the study covered the international GCLP principles that govern the management of human resources, process record keeping, the development of standard operating procedures, the validation of analytical procedures, and the management of biological samples and reference standards in a laboratory. The author considered the key functions of a bioanalytical laboratory and suggested tools to manage them in compliance with the international GCLP principles and the EAEU requirements. It should be noted that scientific publications describe the international practice of applying the GCLP principles fairly well, and the experience of its implementation could be of use to Russian laboratories.CONCLUSION. A bioanalytical laboratory that implements the GCLP principles will increase its competitiveness in the EAEU market for bioanalytical testing services and mitigate its risks of obtaining invalid data.

New Additions to the Mammal List Documented in the Portuguese Red Data Book.

This study outlines the procedures used for collecting, processing, and categorizing data on 16 new mammal species for mainland Portugal, belonging to four taxonomic groups: Eulipotyphla (1), Chiroptera (4), Rodentia (2), and Cetacea (9). Data collection and processing encompassed field and lab work and bibliographic compilation. Data categorization involves, whenever possible, the assessment of the approximate number of mature individuals in populations, the extent of occurrence, and the area of occupancy. The approach employed led to the classification of eight out of the 16 species into an IUCN category: two non-volant small mammals and one bat species were designated as Vulnerable, requiring ongoing monitoring; one rodent and three cetaceans were assigned to Data Deficient due to insufficient available information; and a single bat species was classified as Least Concern due to the high abundance of local populations. For small mammals and bats, alterations to natural systems and climate change emerged as the most relevant threatening factors, while for cetaceans, human activities such as fishing, commercial shipping, and tourism were identified as the primary survival risks. It is recommended to maintain action programs that assist in defining strategic orientations for the implementation of conservation measures on a case-by-case basis.

НАУЧНАЯ ШКОЛА «ПСИХОЛОГО-ПЕДАГОГИЧЕСКОЕ СОПРОВОЖДЕНИЕ СОТРУДНИКОВ УЧРЕЖДЕНИЙ И ОРГАНОВ УГОЛОВНО-ИСПОЛНИТЕЛЬНОЙ СИСТЕМЫ»

The article examines the issues of formation, development and activity of the scientific school “Psychological and pedagogical support of employees of institutions and bodies of the penal system”, functioning at the Faculty of Psychology and Probation of the Academy of the FPS of Russia. It is noted that within the framework of the scientific school there are independent scientific schools (directions). The vectors of activity of their leaders and leading scientists are revealed, the role in training personnel for the penal enforcement system is indicated, attention is focused on the continuity of generations of scientists, the work of scientific laboratories and circles, the description of scientific and representative events held to popularize it.

Development of a robotic-assisted handling and manipulation system for the high-scale bioproduction of 3D-bioprinted organ-on-a-chip devices

Organs-on-a-chip (OoCs) have proven to mimic the basic physiological behavior of organs and the influence of therapeutics on them in greater detail than conventional models, resulting in enormous projected market growth rates. However, the breakthrough to profitable commercialization of that technology has not yet been achieved, partly because the production process chain is characterized by a high proportion of manual laboratory work. The present work addresses this point. Utilizing affordable components, a demonstrator was developed that can be integrated into an existing 3D-bioprinting system and enables the automated production of perfusion-ready OoC devices starting from pre-fabricated injection-molded microfluidic chips. To this end, a corresponding process chain was first defined, and an expandable, configurable algorithm was developed and validated in the form of a finite state machine (FSM). This algorithm controls a modified 4-axis robot arm that covers the steps upstream and downstream of the printing process in the manufacturing process and achieves success rates of up to 100 %. A virtual interface between the robot and printer enables mutual communication and full integration of the algorithm into the process chain. Steps that pose a challenge for the automation of the process chain and appropriate countermeasures and optimizations were identified. This lays the foundation for scaling and standardizing the automated production of OoCs.

A cross-sectional study to correlate nuclear fixative properties of formal saline and clarke’s fluid for histomorphology evaluation of human tissues

Abstract Background: Formal saline is an extensively used cheapest and easily available tissue fixative. However, formalin has been proven to have carcinogenic effects. Clarke’s fluid is an alternative to formal saline and is effective in maintaining the morphological and cellular architecture. Objectives: The objective of the study was to compare the nuclear fixative properties of Clarke’s fluid and formal saline. Materials and Methods: The fresh human tissues of thin skin, large-sized arteries, lymph nodes, spleen, and ileum were obtained from the fresh cadaver. The tissues were fixed in two different fixatives namely 10% formalin and Clarke’s fluid. Then, the tissues were histologically processed. The hematoxylin and eosin-stained serial sections of tissues were graded based on the ease of microtomy, cytoplasmic, and nuclear staining scores. Results: The nuclear properties of all the tissues immersed in Clarke’s fluid showed a median score of 3 and Grade 2 for formal saline; cytoplasmic properties for spleen and skin were median scores of Grade 3 for Clarke’s fluid. The artery was graded 3 for both the fixatives. The Kruskal–Wallis test when applied to nuclear properties, cytoplasmic adequacy, and tissue shrinkage for tissues stained with Clarke’s fluid was statistically significant (P < 0.01). This inferred that Clarke’s fluid is a better nuclear fixative than formal saline. Conclusion: The imminent risks associated with formal saline paved us to explore substitute fixatives, which could provide better results and safety for laboratory workers. Clarke’s fluid is an excellent substitute for formal saline as a nuclear fixative.

Utilizing decellularized bio-membranes to optimize histopathological embedding of small tissues

In recent years, minimally invasive biopsy techniques have been widely used to generate small tissue samples that require processing in clinical pathology. However, small paraffin-embedded tissues are prone to loss due to their small size. To prevent the loss of small tissues, researchers have employed nonbiological embedding materials for preembedding, but this approach can lead to cumbersome experimental procedures and increase the chances of tissue loss. This study aimed to develop a convenient decellularized embedding material derived from biological membrane tissues to effectively protect small tissues from loss during paraffin embedding. This study decellularized three types of fresh animal-derived membrane tissues and selected the small intestine as the most suitable decellularized raw material through attempts at softening, comparing physical properties, and using tissue as the starting material. Subsequently, small tissues from various tissue sources were embedded, followed by H&E staining, Masson staining, immunofluorescence staining, and immunohistochemical staining. The decellularized material derived from biomembrane tissues (DMBT) developed in this study can reduce the loss of small tissues without the need for preembedding, thereby shortening the embedding process. This provides a new pathological embedding tool for future laboratory and clinical research and work.•The fat layer of the pig's small intestine is scraped off, and chemical reagents are used to defat and decellularize it.•Chemical reagents are used to soften and make the pig's small intestine transparent, and the decellularized pig's small intestine is dried.•DMBT is used for embedding and staining the biological tissue.

Replication of soil analogues at the original scale by 3D printing: Quantitative assessment of accuracy and repeatability of the pore structural heterogeneity

The present study investigates the quality of four three-dimensional (3D) printing technologies to accurately reproduce the complex pore structure of a real undisturbed soil sample for laboratory experiments of transport in porous media at a 1:1 scale. Four state-of-the-art 3D printing technologies were evaluated (digital light synthesis, PolyJet with gel support material, low-force stereolithography, and PolyJet with water-soluble support material) using a combination of 3D image analysis from microtomopraphy and flow simulations of the pore structure produced with each 3D printing technique. Accuracy, as determined by matching solid and void volumes, permeability, connected porosity, specific surface area, and pore size distribution of the print against the original digital soil structure, was found to be substantially better for digital light synthesis, as compared to the other tested technologies. Repeatability, as determined by the same metrics but compared between identical prints, was found to be comparable across all printing technologies and did not significantly improve for prints at greater magnification (1.5×). Wettability of the samples was improved by plasma treatment of the prints. The thorough analysis herein presented demonstrates that advanced, yet relatively inexpensive 3D printing approaches can be used to generate real-scale high quality analogs of soils/rocks that are much needed for experimental laboratory work. Such a method can open countless opportunities for studying the coupling of pore-structure and hydrodynamics on reactive mass transport in environmental science and engineering, soil science, and other subsurface related fields.

Kawasaki Disease

Kawasaki disease (KD) is a type of acute inflammation of blood vessels, accompanied by a fever, for which the cause is yet unknown. It primarily affects children who are under the age of five. Kawasaki disease (KD) frequently results in the development of coronary artery lesions (CALs), which include dilated arteries, coronary artery aneurysms (CAAs), and potentially life-threatening myocardial infarction. under the age of five. Kawasaki disease (KD) frequently results in the development of coronary artery lesions (CALs). This case report aims to further explore the diagnosis and the management of KD. In this case report we discuss a 3-year-old male patient who was diagnosed with KD with the main complaints of fever, red eyes, rash, redness of lips with cracked and oral cavity. Patient’s lab work showed hypoalbuminemia, increased D-Dimer, and increased Troponin I. Electrocardiography and echocardiography was performed to observe cardiac complication. Soon aspirin and IVIG and showed an improvement. The child was treated for 6 days and then controlled at the outpatient clinic. Keywords: Kawasaki Disease, Pediatric, IVIG, Aspirin

Bridging Neurobiological Insights and Clinical Biomarkers in Postpartum Depression: A Narrative Review.

Postpartum depression (PPD) affects 174 million women worldwide and is characterized by profound sadness, anxiety, irritability, and debilitating fatigue, which disrupt maternal caregiving and the mother-infant relationship. Limited pharmacological interventions are currently available. Our understanding of the neurobiological pathophysiology of PPD remains incomplete, potentially hindering the development of novel treatment strategies. Recent hypotheses suggest that PPD is driven by a complex interplay of hormonal changes, neurotransmitter imbalances, inflammation, genetic factors, psychosocial stressors, and hypothalamic-pituitary-adrenal (HPA) axis dysregulation. This narrative review examines recent clinical studies on PPD within the past 15 years, emphasizing advancements in neuroimaging findings and blood biomarker detection. Additionally, we summarize recent laboratory work using animal models to mimic PPD, focusing on hormone withdrawal, HPA axis dysfunction, and perinatal stress theories. We also revisit neurobiological results from several brain regions associated with negative emotions, such as the amygdala, prefrontal cortex, hippocampus, and striatum. These insights aim to improve our understanding of PPD's neurobiological mechanisms, guiding future research for better early detection, prevention, and personalized treatment strategies for women affected by PPD and their families.

Modeling and comparison of dissolution profiles for different brands of albendazole boluses

BackgroundAddressing critical veterinary drugs, especially drugs with solubility problems like albendazole, and their implications for therapeutic efficacy, in-vitro dissolution studies can indeed provide valuable insights into how different brands of albendazole boluses perform under standardized conditions, helping to assess their dissolution profiles and potential bioavailability.MethodsSix brands of albendazole 300 mg boluses were collected from December 2020 to May 2021 G.C. The laboratory work was conducted from December 2020 to May 2021 in the National Animal Products and Veterinary Drugs and Feed Quality Assessment Centre (APVD-FQAC) laboratories. The collected brands from government veterinary clinics and private veterinary shops were subjected to model independent and dependent parameters. The dissolution test was conducted according to the USP monograph.ResultsThe study found that none of the six brands met the requirements of the dissolution test, as their API release was less than 80% within the specified 60-minute timeframe according to USP standards. Model independence indicated that only one brand (Alb002 = 3.72) achieved a difference factor of ≤ 15%. The remaining four brands (4/6) did not meet this criterion. However, the similarity factor (f2) revealed that all five brands (5/6) were comparable to the comparator products, with f2 values of \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\:\\ge\\:$$\\end{document}50%. The mean dissolution time results confirmed that three brands (3/6) had the highest dissolution rate and the fastest onset of action. The model-dependent kinetics indicated that the Weibull and Korsemeyer-Peppas models were the best fit for the release of drug substances.ConclusionThe study highlights issues with albendazole boluses’ quality, highlighting the need for national in-vitro dissolution studies. These recommendations could improve quality control, streamline regulatory frameworks, and offer practical, cost-effective methods for evaluating drug efficacy and safety, ensuring veterinary pharmaceuticals meet safety and efficacy standards.

Fabrication of Low-Cost Flexible Paper-Based Alcohol Sensor

The development of alcohol sensors has been an active research area for years. Alcohol detection can be applied to medicine, agriculture, and law enforcement. On the Navajo Nation, we have limited access to centralized analytical laboratory techniques, for on-spot testing. Regarding healthcare, the collected lab sample is sent to nearby bigger cities for analysis, and results for lab work may take weeks and even months to receive a detailed report; also, law enforcement relies on state support for analytical techniques. Through the NSF-PREM research collaboration with Harvard University at the NanoElectrochemical Analysis and Energy Storage Laboratory (NEST LAB) at Navajo Technical University (NTU), we have fabricated a versatile paper-based sensor to detect several analytes. Our sensor utilizes electrochemical analytical techniques such as cyclic voltammetry to monitor the concentrations of our target analytes (alcohol). Our sensors' versatility and low-cost appeal make them suitable for alcohol detection. We can optimize our sensor to detect alcohol samples for on-spot analysis. We can also apply our sensors to detect and determine alcohols derived from the biomass. Contact Details: Justin Platero, Student Researcher, Email:justin.platero@student.navajotech.edu * Corresponding Author: Dr. Thiagarajan Soundappan, PI, NEST LAB, NTU. Email: tsoundappan@navajotech.edu Acknowledgment: NSF-PREM DMR-2122195 and USDA-NIFA-2021-38424-33455

Towards unified reporting of genome sequencing results in clinical microbiology.

Whole genome sequencing (WGS) has become a vital tool in clinical microbiology, playing an important role in outbreak investigations, molecular surveillance, and identification of bacterial species, resistance mechanisms and virulence factors. However, the complexity of WGS data presents challenges in interpretation and reporting, requiring tailored strategies to enhance efficiency and impact. This study explores the diverse needs of key stakeholders in healthcare, including clinical management, laboratory work, public surveillance and epidemiology, infection prevention and control, and academic research, regarding WGS-based reporting of clinically relevant bacterial species. In order to determine preferences regarding WGS reports, human-centered design approach was employed, involving an online survey and a subsequent workshop with stakeholders. The survey gathered responses from 64 participants representing the above mentioned healthcare sectors across geographical regions. Key findings include the identification of barriers related to data accessibility, integration with patient records, and the complexity of interpreting WGS results. As the participants designed their ideal report using nine pre-defined sections of a typical WGS report, differences in needs regarding report structure and content across stakeholders became evident. The workshop discussions further highlighted the need to feature critical findings and quality metrics prominently in reports, as well as the demand for flexible report designs. Commonalities were observed across stakeholder-specific reporting templates, such as the uniform ranking of certain report sections, but preferences regarding the depth of content within these sections varied. Using these findings, we suggest stakeholder-specific structures which should be considered when designing customized reporting templates. In conclusion, this study underscores the importance of tailoring WGS-based reports of clinically relevant bacteria to meet the distinct needs of diverse healthcare stakeholders. The evolving landscape of digital reporting increases the opportunities with respect to WGS reporting and its utility in managing infectious diseases and public health surveillance.

Design and Implementation of a 3 Degrees of Freedom Robotic Arm Powered by Pneumatic Artificial Muscle

The development of a 3-DOF robotic arm powered by pneumatic artificial muscles is represented as an innovative approach in the field of robotics, with the advantages of lightweight and flexible design being combined with the power and control benefits of pneumatic actuation. The design process, challenges, and solutions that were encountered in the development of the robotic arm are outlined in this paper, with an emphasis on its potential applications in industrial and research settings being highlighted. Additionally, the robotic arm’s modular design is enabled to allow easy customization and scalability, making it possible for the arm to be tailored to a wide range of tasks, from precise laboratory work to more robust industrial applications.

Employing educational data mining techniques to predict programming students at-risk of dropping out

This research primary aimed at evaluating various predictive models in predicting programming students at risk of dropping out. It also aimed at identifying attributes that are significant in predicting students at risk of dropping. The educational data mining process (EDM) was utilized as the research framework. The study conducted a ten-fold cross-validation, revealing that the k-nearest neighbors (kNN) algorithm achieved the highest classification accuracy at 95.5%. The decision tree model followed closely with a 94.9% accuracy, logistic regression exhibited 94.4%, and the neural network model yielded a classification accuracy of 93.2%. Further analysis, including confusion matrices and receiver operating characteristic (ROC) curves, provided detailed insights into the models' performance. Notably, the decision tree algorithm excelled in identifying students who did not drop out, with a misclassification rate of 9 out of 30 for dropped students. Analysis also showed that students’ assignments completed (AC), laboratory work (LW), and attendance (ATT) were the strongest predictors in identifying students at risk of dropping. Results of the study can be used by instructors to identify in advance student at risk of dropping and provide them with the necessary intervention to improve performance in programming.

Evaluating the Status of Hepatitis B Vaccination in Healthcare Workers at a Central Laboratory in a Tertiary Care Hospital and Research Centre.

Introduction Hepatitis B virusis a significant occupational hazard for healthcare workers worldwide. Long-term protection against hepatitis B infection is conferred by the vaccineand the protective immune response is indicated by anti-hepatitis B surface antigen (HBsAg) titre. It is crucial to monitor anti-HBsAg titres as their levels decrease over time. The study aims to evaluate thestatus of hepatitis B vaccination among personnel working in the Central Laboratory of Shri B.M. Patil Medical College Hospital and Research Centre. The focus is on understanding the immunization practices and protection levels against HBV within this high-risk group. Materials and methods A cross-sectional analysis was conducted, including collecting demographic data, determining HBsAgstatus, evaluating anti-HBsAg titre value, and getting vaccination details of the laboratory personnel. The study participants included doctors, lab technicians, and attendants who were assessed for both vaccination coverage and immunity levels. After obtaining their written consent, 4 ml of blood was collected in sterile blood collection tubes. All the samples were tested for HBsAg. The negative samples were tested for anti-hepatitis B surface antigen antibody (HBsAg-Ab (IgG)) titre. The enzyme-linked immunosorbent assay (ELISA) method was used to evaluate the obtained samples for HBsAg and anti-HBsAg titre. Results A total of 99 healthcare workerswere included in the study. Most of the laboratory healthcare workers were in the age range of 20-30 years.In 84.8% of the subjects, protective antibody levels (>10 IU/ml) were found. The highest protection was seen among doctors (94.5%), followed by lab technicians (82.9%) and attendants (66.6%). However, 15.2% exhibited inadequate immunity, predominantly among the attendants (33.3%). The highest vaccination coverage was among doctors (91.8%), followed by lab technicians (78.7%) and attendants (53.3%). Most doctors had completed the full vaccination schedule (70.2%) or received a booster dose (24.3%) compared to lab technicians (57.4%)and attendants (46.6%). Conclusion The study highlights effective preventive measures against HBV among laboratory healthcare workers, as indicated by the absence of active infections. But it also emphasizes the necessity of focused initiatives to raise vaccination rates, particularly among attendants, in order to guarantee complete protection against HBV for all levels of laboratory workers.

Presentation of a distributed testing infrastructure for joint experiments across multiple remote laboratories for robust development of new district heating concepts

4th-generation district heating networks confront numerous challenges such as integrating decentralized renewable energy sources, bidirectional heat transfer, new storage concepts, low-temperature operation, custom heat supply, data management, and advanced control strategies. Laboratory and hardware-in-the-loop testing offer a safe, cost-effective environment for testing and validating these innovations. This paper presents a framework for joint experiments in multiple remote laboratories, enhancing the testing of district heating system components. This distributed testbed enhances the efficiency of testing by utilizing existing equipment and expertise from various laboratories, thereby reducing costs and time and allowing for more scenarios to test. It targets manufacturers, grid operators, and research institutions, facilitating collaborative lab work for technology testing before field deployment. This approach allows for diverse test scenarios, considering component interactions across different locations without identical hardware or software. The framework's efficacy is shown in a proof-of-concept with a low-temperature district heating network integrated across four Fraunhofer Institutes. An initial experiment connects a test building and a ground-source heat pump physically existing in different labs with emulated models of a district heating network and a geothermal source. Results from a three-week operation validate the framework's performance.

Efficiently assessing the early-age cracking risk of cementitious materials with a mini temperature stress testing machine

Temperature Stress Testing Machine (TSTM) is a universal testing tool for many properties relevant to early-age cracking of cementitious materials. However, the complexity of TSTMs require heavy lab work and thus hinders a more thorough parametric study on a range of cementitious materials. This study presents the development and validation of a Mini-TSTM for efficiently testing the autogenous deformation (AD), viscoelastic properties, and their combined results, the early-age stress (EAS). The setup was validated through systematic tests of EAS, AD, elastic modulus, and creep. Besides, the heating/cooling capability of the setup was examined by tests of coefficient of thermal expansion by temperature cycles. The results of EAS correspond well to that of AD, which qualitatively validates the developed setup. To quantitatively validate the setup, a classical viscoelastic model was built, based on the scenario of a 1-D uniaxial restraint test, to predict the EAS results with the tested AD, elastic modulus, and creep of the same cementitious material as the input. The predicted EAS matched the testing results of Mini-TSTM with good accuracy in 6 different cases. The viscoelastic model also provided quantitative explanations for why variations in early AD do not influence the EAS results. The testing and modelling results together validate the developed Mini-TSTM setup as an efficient tool for studying early-age cracking of cementitious materials. At the end, the potential limitations of the Mini-TSTM are discussed and its applicability for concrete with aggregate size up to 22 mm is demonstrated.

Pregnancy after advanced ovarian cancer with spontaneous uterine rupture in second trimester: A case report and review of the literature.

Fertility-preserving surgery (FPS) in advanced ovarian cancer (AOC) is extremely rare and consequently, information about the pregnancies of these patients is anecdotal. Therefore, management of the pregnancy after AOC is challenging, especially if an unexpected situation arises. A 31-year-old nulliparous woman was admitted to our tertiary hospital in the 18th week of twin pregnancy with sudden severe abdominal pain. Her medical history included a low-grade AOC stage IIIc diagnosed 2 years before pregnancy and treated by debulking FPS and systemic therapy with carboplatin/paclitaxel and bevacizumab. Clinical examination described normal vital signs and peritoneal irritation without any vaginal discharge. Sonography revealed free fluid in the pouch of Douglas and intact twin pregnancy. Laboratory work showed elevated leukocytes with neutrophilia. To evaluate appendicitis magnetic resonance imaging of the abdomen was indicated. This revealed a uterine rupture with the now extra-cavitary position of the twins. Simultaneously, the patient's symptoms deteriorated, and emergency surgery was necessary where hemoperitoneum with avital fetuses were present. Despite excessive blood loss the uterus could be repaired and preserved. Previous resection of the uterine serosa during her debulking FPS, administration of bevacizumab affecting smooth muscles, and overstretching the uterus in the twin pregnancy were considered as possible risk factors for the presenting uterine rupture. Pregnancy after AOC is possible but should be monitored closely, especially due to the hidden long-term consequences of its therapy. In the differential diagnosis of sudden abdominal pain during pregnancy uterine rupture should be considered even in patients with an unscared uterus.

Unlocking the Potential of Clustering and Classification Approaches: Navigating Supervised and Unsupervised Chemical Similarity.

The field of toxicology has witnessed substantial advancements in recent years, particularly with the adoption of new approach methodologies (NAMs) to understand and predict chemical toxicity. Class-based methods such as clustering and classification are key to NAMs development and application, aiding the understanding of hazard and risk concerns associated with groups of chemicals without additional laboratory work. Advances in computational chemistry, data generation and availability, and machine learning algorithms represent important opportunities for continued improvement of these techniques to optimize their utility for specific regulatory and research purposes. However, due to their intricacy, deep understanding and careful selection are imperative to align the adequate methods with their intended applications. This commentary aims to deepen the understanding of class-based approaches by elucidating the pivotal role of chemical similarity (structural and biological) in clustering and classification approaches (CCAs). It addresses the dichotomy between general end point-agnostic similarity, often entailing unsupervised analysis, and end point-specific similarity necessitating supervised learning. The goal is to highlight the nuances of these approaches, their applications, and common misuses. Understanding similarity is pivotal in toxicological research involving CCAs. The effectiveness of these approaches depends on the right definition and measure of similarity, which varies based on context and objectives of the study. This choice is influenced by how chemical structures are represented and the respective labels indicating biological activity, if applicable. The distinction between unsupervised clustering and supervised classification methods is vital, requiring the use of end point-agnostic vs. end point-specific similarity definition. Separate use or combination of these methods requires careful consideration to prevent bias and ensure relevance for the goal of the study. Unsupervised methods use end point-agnostic similarity measures to uncover general structural patterns and relationships, aiding hypothesis generation and facilitating exploration of datasets without the need for predefined labels or explicit guidance. Conversely, supervised techniques demand end point-specific similarity to group chemicals into predefined classes or to train classification models, allowing accurate predictions for new chemicals. Misuse can arise when unsupervised methods are applied to end point-specific contexts, like analog selection in read-across, leading to erroneous conclusions. This commentary provides insights into the significance of similarity and its role in supervised classification and unsupervised clustering approaches. https://doi.org/10.1289/EHP14001.

Comparing the Pulmonary-Spirometry In Laboratory Workers Who Wear Acchadana® and KN95® Masks

BACKGROUND : The upper respiratory tract is susceptible to inflammation caused by exposure to airborne contaminants, particularly chemical irritants. Inhaled irritant gases can lead to various symptoms and adverse reactions in the respiratory tract. Laboratory workers are at a high risk of respiratory tract inflammation due to exposure to volatile chemicals. The use of personal protective equipment (PPE), such as masks, is essential to prevent inflammation and protect the respiratory tract. Lung function tests using spirometry, including Forced Vital Capacity (FVC), Forced Expiratory Volume in One Second (FEV1.0), and Peak Expiratory Flow (PEF), can help identify abnormalities in lung function. AIMS : The primary objective of this investigation is to juxtapose the pulmonary conditions of laboratory workers before and after the utilization of KN95® masks and Acchadana® masks. METHOD : The study design was a Randomized Control Trial, and the subjects were divided into two groups: the control group wearing KN95 masks and the treatment group wearing Acchadana® herbal masks. Spirometry measurements were taken before and after using the masks, and statistical analysis was conducted to compare the results. RESULT : The results showed that both mask groups experienced improvements in lung function parameters after using the masks. However, the KN95 mask group showed better lung conditions compared to the Acchadana® mask group. CONCLUSION : Spirometry tests conducted on lab workers revealed improved lung function metrics (including FVC, FEV1.0, and PEF) following the usage of KN95 masks and Acchadana® herbal masks. The KN95 mask users exhibited superior respiratory health compared to the other group in this investigation.