Research Laboratory Setting Research Articles

Prostaglandin E2 regulates the plasminogen activator pathway in human endometrial endothelial cells: a new in vitro model to investigate heavy menstrual bleeding

To study the role of PGE2 in regulating plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) in human primary endometrial endothelial cells (HEECs) from women with normal menstrual bleeding (NMB) and heavy menstrual bleeding (HMB). In vitro study using endometrial endothelial cells. Research laboratory setting. Women with normal menstrual bleeding (NMB) and heavy menstrual bleeding (HMB) provided endometrial biopsy samples. PGE2 and PGE2 receptor-selective agonists were administered to cultured HEECs. Levels of PAI-1 and tPA in NMB-HEECs and HMB-HEECs after treatment with PGE2 and receptor-selective agonists. PGE2 increased total PAI-1 levels in NMB-HEECs, but not in HMB-HEECs, which had higher baseline PAI-1 levels. PTGER1 and PTGER2 agonists increased PAI-1 in NMB-HEECs, while PTGER3 and PTGER4 did not. PGE2 had no effect on tPA levels in either NMB-HEECs or HMB-HEECs. PGE2, through PTGER1 and PTGER2, regulates the plasminogen activator system in NMB-HEECs, suggesting a role in reducing fibrinolytic activity during normal menstrual cycles. The lack of PGE2 effect and elevated baseline PAI-1 in HMB-HEECs support using this in vitro model to further understand prostaglandin pathways in normal and heavy menstrual bleeding.

Optically accessible gas exposure apparatus for testing and characterization of holographic gas sensors

Holographic gas sensors are of great interest due to their widespread applicability and potential for high sensitivity, fast response, immunity to electromagnetic interference, and compact and lightweight nature. For effective design and development of holographic gas sensors, it is essential to have a reliable and safe gas exposure system allowing for optical access for testing purposes. Here, the design and operation of a custom gas exposure apparatus for the performance evaluation of holographic grating-based gas sensors within a research laboratory setting is presented. The apparatus enables the real-time measurement of analyte-induced changes in key holographic grating parameters: grating diffraction efficiency and reconstruction wavelength. A demonstration of the capabilities of the optically accessible apparatus to evaluate sensor response time, sensitivity to different volatile organic compound analytes, and response to cyclical gas exposure is presented. The AutoCAD designs, as well as the material and equipment specifications for the custom apparatus, are provided to facilitate reproduction of the gas development and gas exposure setup.

Validation of Single-Nucleotide Mosaic Variants Through Droplet Digital PCR.

The detection, validation, and subsequent interpretation of potentially mosaic single-nucleotide variants (SNV) within next-generation sequencing data remains a challenge in both research and clinical laboratory settings. The ability to identify mosaic variants in high genome coverage sequencing data at levels of ≤1% underscores the necessity for developing guidelines and best practices to verify these variants orthogonally. Droplet digital PCR (ddPCR) has proven to be a powerful and precise method that allows for the determination of low-level variant fractions within a given sample. Herein we describe two precise ddPCR methods using either a fluorescent TaqMan hydrolysis probe approach or an EvaGreen fluorescent dye protocol. The TaqMan approach relies on two different fluorescent probes (FAM and HEX/VIC), each designed to amplify selectively only in the presence of a single nucleotide change denoting the variant or reference position. The fractional abundance is then calculated to determine the relative quantities of both alleles in the final sample. The EvaGreen protocol relies on two independent reactions with oligonucleotide primers designed with the single nucleotide change denoting the variant at the penultimate position of the primer. The relative amplification efficiency of both primer sets (reference and variant) can be compared to determine the mosaic level of a given variant. As the cost of high-coverage sequencing continues to decrease, the identification of potentially mosaic variants will also increase. The approaches outlined will allow clinicians and researchers a more precise determination of the true mosaic level of a given variant allowing them to better assess not only its potential pathogenicity but also its possible recurrence risk when offering genetic counseling to families. © 2024 Wiley Periodicals LLC. Basic Protocol: Droplet digital PCR (ddPCR) with TaqMan hydrolysis probes Alternate Protocol: EvaGreen oligonucleotide-specific ddPCR.

Remote olfactory assessment using the NIH Toolbox Odor Identification test and the brain health registry.

Early identification of deficits in our ability to perceive odors is important as many normal (i.e., aging) and pathological (i.e., sinusitis, viral, neurodegeneration) processes can result in diminished olfactory function. To realistically enable population-level measurements of olfaction, validated olfaction tests must be capable of being administered outside the research laboratory and clinical setting. The purpose of this study was to determine the feasibility of remotely testing olfactory performance using a test that was developed with funding from the National Institutes of Health as part of a ready-to-use, non-proprietary set of measurements useful for epidemiologic studies (NIH Toolbox Odor ID Test). Eligible participants older than 39 years and active (within 6 months) in the Brain Health Registry (BHR), an online cognitive assessment platform which connects participants with researchers, were recruited for this study. Interested participants were mailed the NIH Toolbox Odor ID Test along with instructions on accessing a website to record their responses. Data obtained from subjects who performed the test at home was compared to the normative data collected when the NIH Toolbox Odor ID Test was administered by a tester in a research setting and validated against the Smell Identification Test. The age-range and composition of the population ensured we had the ability to observe both age-related decline and gender-related deficits in olfactory ability, as shown in the experimental setting. We observed that age-associated olfactory decline and gender-associated performance was comparable to performance on the administered test. Self-administration of this test showed the age-related loss in olfactory acuity, F(4, 1156)=14.564, p<.0001 as well as higher accuracy for women compared to men after controlling for participants' age, F(1, 1160) = 22.953, p <.0001. The effect size calculated as Hedge's g, was 0.41. These results indicate that the NIH Toolbox Odor ID Test is an appropriate instrument for self-administered assessment of olfactory performance. The ability to self-administer an inexpensive olfactory test increases its utility for inclusion in longitudinal epidemiological studies and when in-person testing is not feasible.

The Classroom‐Research‐Mentoring Framework: A lens for understanding science practice‐based instruction

AbstractReformed science curricula provide opportunities for students to engage with authentic science practices. However, teacher implementation of such curricula requires teachers to consider their role in the classroom, including realigning instructional decisions with the epistemic aims of science. Guiding newcomers in science can take place in settings ranging from the classroom to the undergraduate research laboratory. We suggest thinking about the potential intersections of guiding students across these contexts is important. We describe the Classroom‐Research‐Mentoring (CRM) Framework as a novel lens for examining science practice‐based instruction. We present a comparative case study of two teachers as they instruct undergraduate students in a model‐based inquiry laboratory. We analyzed stimulated‐recall episodes uncovering how these teachers interacted with their students and the rationale behind their instructional choices. Through the application of the CRM Framework, we revealed ways teachers can have instructional goals that align with those of a research mentor. For example, our teachers had the goals of “creating an inclusive environment open to student ideas,” “acknowledging students as scientists,” and “focusing students on skills and ideas needed to solve biological problems.” We suggest three functions of research mentoring that translate across the classroom and research laboratory settings: (1) build a shared understanding of epistemic aims, (2) support learners in the productive use of science practices, and (3) motivate learner engagement in science practices.

International comparisons of intraocular pressures, as measured by Tono-Pen and Goldmann applanation tonometry, in healthy adults: A meta-analysis.

Investigate intraocular pressure (IOP), as measured by Tono-Pen (TP) and Goldmann applanation tonometry (GAT), in healthy adults. Provide an updated synthesis of multinational, primary studies, reported during the 10-year period 2011 to 2021 and offer an evidence-based benchmark, against which IOP can be evaluated across subject variables and pathologies. Three primary research questions are investigated: Is there a statistically significant difference between IOP measured by TP and GAT? If yes, is the difference clinically significant? Is measurement of IOP affected by the country or setting location, in which the measurements are made? An aggregate meta-analysis was conducted on 22 primary studies, from 15 different countries. IOP measurements were made from each healthy adult subject, with both the TP and GAT. Primary studies were identified and data extracted according to recommended preferred reporting items for systematic reviews and meta-analysis protocol guidelines. Meta-analysis summary results are reported as the point estimate of the raw mean difference of IOP. Meta-analysis reveals a statistically significant difference in raw mean differences in IOP, when measured by TP and GAT, in the healthy adult population. Tono-Pen IOP measurements are higher than GAT IOP measurements. The point estimate for the summary effect size = -0.73 mm Hg, P = .03. The prediction interval for the true effect size, in 95% of all comparable populations, is -4.03 to 2.58 mm Hg. There is no clinically significance difference in IOP when measured by TP and GAT. Meta-regression analysis reveals statistically significant differences in measurement of IOP by countries, R2 analog = 0.75, P = .001. There is no statistically significant difference in measurement of IOP as a function of measurement location setting, R2 analog = -0.17, P = .65. IOP measured by TP are marginally higher compared to GAT, in the healthy adult population. However, from a clinical practice perspective, TP and GAT produce similar IOP measurements. There is evidence of significant variabilities in IOP measurements as a function of country. IOP measurements collected in a research laboratory setting are similar to IOP collected in a clinical setting. Results have implications for the primary care physician requiring a portable, inexpensive, reliable, and easily administered instrument to assess IOP.

Parasitoid Wasp Culturing and Assay to Study Parasitoid-induced Reproductive Modifications in Drosophila.

In nature, parasitoid wasp infections are a major cause of insect mortality. Parasitoid wasps attack a vast range of insect species to lay their eggs. As a defense, insects evolved survival strategies to protect themselves from parasitoid infection. While a growing number of studies reported both host defensive tactics and parasitoid counter-offensives, we emphasize that this parasite-host relationship presents a unique ecological and evolutionary relevant model that is often challenging to replicate in a laboratory. Although maintaining parasitoid wasp cultures in the laboratory requires meticulous planning and can be labor intensive, a diverse set of wasp species that target many different insect types can be maintained in similar culture conditions. Here, we describe the protocol for culturing parasitoid wasp species on Drosophila larvae and pupae in laboratory conditions. We also detail an egg-laying assay to assess the reproductive modification of Drosophila females in response to parasitoid wasps. This behavioral study is relatively simple and easily adaptable to study environmental or genetic influences on egg-laying, a readout for female germline development. Neither the parasitoid culture conditions or the behavioral assay require special supplies or equipment, making them a powerful and versatile approach in research or teaching laboratory settings. Graphical abstract.

Habitual walking speed and fatigue explain self-reported functional capacity after stroke.

Individuals after stroke present several motor impairments, which reduced the functional capacity. The understanding of modifiable factors which are related to functional capacity in individuals with chronic stroke could better direct clinical practice. However, the mechanisms that could influence functional capacity in individuals with chronic stroke are not fully understood. This study aimed to determine which modifiable variables would best predict self-reported functional capacity after stroke. Cross-sectional. Research laboratory setting. Ninety two individuals with chronic stroke, who had a mean age of 60 (SD 13) years and a time since the onset of the stroke of 52 (67) months. Regression analysis of cross-sectional data was used to investigate whether body mass index, habitual walking speed, physical activity levels, fatigue, motor recovery, walking distance, and residual strength deficits of the lower limb muscles would predict self-reported functional capacity. Habitual walking speed alone explained 48% of the variance in functional capacity. When fatigue was included in the model, the explained variance increased to 55%. Habitual walking speed and fatigue were significant predictors of self-reported functional capacity in individuals with chronic stroke. These individuals may increase their functional capacity with interventions aimed at increasing walking speed and reducing fatigue.

Fabrication of an inexpensive injection molding instrument for rapid prototyping of high precision parts

Polymeric drug delivery devices are among the most promising avenues to improve the equitable distribution of life-saving medications throughout the world. At present, most research into manufacturing these devices relies heavily on solvent-based methods, limiting scalability, reproducible manufacture, and potentially leading to cytotoxicity. Solvent-free polymeric biomedical implants manufactured through traditional thermal processing methods eliminate the bulk of these concerns. However, they are difficult to manufacture in a research laboratory setting. Investigation of manufacturing techniques such as injection molding has been limited in the past due to the high upfront cost of polymer equipment and the large scale necessary to conduct pilot experiments. This study describes a low-cost bench-top milliliter-volume vacuum injection-molding system capable of pilot-scale injection molding of small shapes of arbitrary geometry. The plans presented herein open this convenient and scalable manufacturing technique to academic research laboratories interested in pilot-scale experiments with polymeric devices. Polymers relevant for polymeric drug or vaccine delivery are investigated, and a demonstration of the fabrication of simple geometric parts and solvent-free polymeric microneedle patches is described. In particular, microneedle patches demonstrate the capabilities and limitations of producing fine feature sizes for biomedically relevant products.

Neuromuscular Consequences of Lumbopelvic Dysfunction: Research and Clinical Perspectives.

Injuries involving the lumbopelvic region (ie,lumbar spine, pelvis, hip) are common across the lifespan and include pathologies such as low back pain, femoroacetabular impingement syndrome, labrum tear, and osteoarthritis. Joint injury is known to result in an arthrogenic muscle response which contributes to muscle weakness and altered movement patterns. The purpose of this manuscript is to summarize the arthrogenic muscle response that occurs across lumbopelvic region pathologies, identify methods to quantify muscle function, and propose suggestions for future research. While each lumbopelvic region pathology is unique, there are a few common impairments and a relative consistent arthrogenic muscle response that occurs across the region. Hip muscle weakness and hip joint range of motion limitations occur with both lumbar spine and hip pathologies, and individuals with low back pain are known to demonstrate inhibition of the transversus abdominis and multifidus. Assessment of muscle inhibition is often limited to research laboratory settings, but dynamometers, ultrasound imaging, and electromyography offer clinical capacity to quantify muscle function and inform treatment pathways. Future studies should systematically determine the arthrogenic muscle response across multiple muscle groups and the timeline for changes in muscle function and determine whether disinhibitory modalities improve functional outcomes beyond traditional treatment approaches.

Are We Sailing in the Right Direction for Deeper Insights Into Acceptance? Evidence From a Systematic Review of Research in Laboratory Settings.

This systematic review aims to review and update the current state of research on the acceptance strategy for a healthy population in a laboratory setting. Using a previously defined search strategy, the PsycInfo, PubMed, and Web of Science databases were searched from 1961 to May 2020 for articles on this topic. Twenty-five high-quality articles, involving a total of 2265 participants, met inclusion criteria. According to these results, acceptance is a strategy with promising outcomes for handling pain in healthy populations, although its superiority over other strategies to reduce negative affect, anger, and other pain variables is unclear. The instructions and outcome variables vary widely between studies, and few studies compare acceptance with mindfulness. We discuss these findings and provide information to guide future researchers for designing fine-grained investigations that can address the gaps in this area.

A research note: Using ethics memoranda of understanding in community-based research

Because university-based research ethics committees tend to focus on ethical dilemmas common in biomedical research in laboratory settings, a growing number of researchers and community-based organizations have articulated the need for alternatives to such committees in community-based research. While there is a robust academic literature on ethical dilemmas in such social research, there remains a need for practical tools to use in collaborations between communities and researchers. In this research note, I present potential memoranda of understanding between academics and communities that might be used when formal community-based research ethics committees do not exist. I focus on two hypothetical scenarios, in which a researcher works with an established group or organization, and in which a researcher is just one of several researchers working with the same community. I forward a framework that conceptualizes researchers as critical friends of communities in their research, highlighting questions of emotional labor, community benefits, and what I call generative conflicts. I hope that researchers and community-based organizations find this note to be a useful starting point for constructive dialogs on reciprocity in community-based research.

Typical, atypical and cryptic t(15;17)(q24;q21) (PML::RARA) observed in acute promyelocytic leukemia: A retrospective review of 831 patients with concurrent chromosome and PML::RARA dual-color dual-fusion FISH studies.

The diagnosis of acute promyelocytic leukemia (APL) relies on the identification of PML::RARA fusion. While the majority of APL cases harbor a typical t(15;17)(q24;q21), atypical genetic mechanisms leading to the oncogenic PML::RARA fusion have been reported yet their frequency and scope remain poorly characterized. We assessed the genetic findings of 831 cases with APL investigated with concurrent chromosome banding analysis and dual-color dual-fusion fluorescence in situ hybridization (D-FISH) analysis at our institution over an 18.5-year timeframe. Seven hundred twenty-three (87%) cases had a typical balanced t(15;17) with both testing modalities. Atypical karyotypic results including complex translocations, unbalanced rearrangements and insertional events occurred in 50 (6%) cases, while 6 (0.7%) cases were cryptic by conventional chromosome studies despite PML::RARA fusion by D-FISH evaluation. Atypical FISH patterns were observed in 48 (6%) cases despite apparently balanced t(15;17) on chromosome banding analysis. Two hundred fifty (30%) cases displayed additional chromosome abnormalities of which trisomy/tetrasomy 8 (37%), del(7q)/add(7q) (12%), and del(9q) (7%) were most frequent. Complex and very complex karyotypes were observed in 81 (10%) and 34 (4%) cases, respectively. In addition, 4 (0.5%) cases presented as an apparently doubled, near-tetraploid stemline clone. This report provides the largest appraisal of cytogenetic findings in APL with conventional chromosome and PML::RARA D-FISH analysis. By characterizing the frequency and breadth of typical and atypical results through the lens of these cytogenetic testing modalities, this study serves as a pragmatic source of information for those involved in the investigation of APL in both the clinical and research laboratory settings.

Alpha oscillations related to self-other integration and distinction during live orchestral performance: A naturalistic case study.

Ensemble music performance requires musicians to achieve precise interpersonal coordination while maintaining autonomous control over their own actions. To do so, musicians dynamically shift between integrating other performers' actions into their own action plans and maintaining a distinction between their own and others' actions. Research in laboratory settings has shown that this dynamic process of self-other integration and distinction is indexed by sensorimotor alpha oscillations. The purpose of the current descriptive case study was to examine oscillations related to self-other integration and distinction in a naturalistic performance context. We measured alpha activity from four violinists during a concert hall performance of a 60-musician orchestra. We selected a musical piece from the orchestra's repertoire and, before analyzing alpha activity, performed a score analysis to divide the piece into sections that were expected to strongly promote self-other integration and distinction. In line with previous laboratory findings, performers showed suppressed and enhanced alpha activity during musical sections that promoted self-other integration and distinction, respectively. The current study thus provides preliminary evidence that findings from carefully controlled laboratory experiments generalize to complex real-world performance. Its findings also suggest directions for future research and potential applications of interest to musicians, music educators, and music therapists.

Using Artificial Intelligence for Assistance Systems to Bring Motor Learning Principles into Real World Motor Tasks.

Humans learn movements naturally, but it takes a lot of time and training to achieve expert performance in motor skills. In this review, we show how modern technologies can support people in learning new motor skills. First, we introduce important concepts in motor control, motor learning and motor skill learning. We also give an overview about the rapid expansion of machine learning algorithms and sensor technologies for human motion analysis. The integration between motor learning principles, machine learning algorithms and recent sensor technologies has the potential to develop AI-guided assistance systems for motor skill training. We give our perspective on this integration of different fields to transition from motor learning research in laboratory settings to real world environments and real world motor tasks and propose a stepwise approach to facilitate this transition.

Exploring Vestibular Ocular Motor Screening in Adults With Persistent Complaints After Mild Traumatic Brain Injury.

The purpose of this study was to (1) explore differences in vestibular ocular motor screening (VOMS) symptoms between healthy adults and adults with persistent symptoms after mild traumatic brain injury (mTBI), and (2) explore the relationships between VOMS symptoms and other measures (self-reported vestibular symptoms, clinical measures of balance and gait, and higher-level motor ability tasks). Research laboratory setting. Fifty-three persons with persistent symptoms (>3 weeks) following mTBI and 57 healthy controls were recruited. Eligibility for participation included being 18 to 50 years of age and free of medical conditions that may affect balance, with the exception of recent mTBI for the mTBI group. Cross-sectional. The primary outcomes were the VOMS symptom scores and near point of convergence (NPC) distance. Secondary outcomes included the Dizziness Handicap Inventory (DHI) total and subdomain scores, sway area, Functional Gait Analysis total score, gait speed, and modified Illinois Agility Task completion time, and Revised High-Level Mobility Assessment Tool total score. The mTBI group reported more VOMS symptoms ( z range, -7.28 to -7.89) and a further NPC ( t = -4.16) than healthy controls (all P s < .001). DHI self-reported symptoms (total and all subdomain scores) were strongly associated with the VOMS symptom scores (rho range, 0.53-0.68; all P s < .001). No significant relationships existed between VOMS symptoms and other measures. Significant group differences support the relevance of the VOMS for mTBI in an age-diverse sample with persistent symptoms. Furthermore, strong association with DHI symptoms supports the ability of the VOMS to capture vestibular complaints in this population.

Diet Composition and Objectively Assessed Sleep Quality: A Narrative Review

Insufficient sleep is highly prevalent in society and has tremendous negative health consequences. Despite the available treatments, there is continued demand for novel and natural strategies to promote better sleep. Dietary modifications could be a viable new target to improve sleep. A literature review using PubMed was conducted on studies that examined the relationship between diet composition (ie, macronutrients or special diets) and objectively assessed sleep quality. Twenty human studies (6 observational and 14 interventional) published between 1975 and March 2021 met the eligibility criteria and were included. The amount of dietary carbohydrates and fats was associated with both better and worse sleep quality indices. However, the type of carbohydrate and fat was an important factor in these associations, with diets higher in complex carbohydrates (eg, fiber) and healthier fats (eg, unsaturated) being associated with better sleep quality. Diets higher in protein were associated with better sleep quality. In general, diets rich in fiber, fruits, vegetables, and anti-inflammatory nutrients and lower in saturated fat (eg, Mediterranean diet) were associated with better sleep quality. The connection between diet and sleep quality warrants further investigation. Rigorous interventional studies of longer duration assessing the effects of whole foods, rather than isolated nutrients, and under free-living conditions, rather than in a research laboratory setting, as well as mechanistic studies are needed to better understand how dietary patterns relate to sleep quality. Future research could provide insights into whether dietary modifications could be an effective, personalized strategy for improving sleep quality in millions of Americans.

Validation of a Classroom Version of the Eating in the Absence of Hunger Paradigm in Preschoolers.

Eating in the absence of hunger (EAH), a measure of children's propensity to eat beyond satiety in the presence of highly palatable food, has been associated with childhood obesity and later binge eating behavior. The EAH task is typically conducted in a research laboratory setting, which is resource intensive and lacks ecological validity. Assessing EAH in a group classroom setting is feasible and may be a more efficient alternative, but the validity of the classroom assessment against the traditional individually-administered paradigm has not been tested. The objective of this study was to compare EAH measured in a classroom setting to the one-on-one version of the paradigm in a sample of Head Start preschoolers. Children (n = 35) from three classrooms completed both classroom and individual EAH tasks in a random, counterbalanced order. In the group condition, children sat with peers at their classroom lunch tables; in the individual condition, children met individually with a researcher in a separate area near their classroom. In both conditions, following a meal, children were provided free access to generous portions of six snack foods (~750 kcal) and a selection of toys for 7 min. Snacks were pre- and post-weighed to calculate intake. Parents completed a survey of their child's eating behaviors, and child height and weight were measured. Paired t-tests and intraclass correlation coefficients were used to compare energy intake between conditions, and correlations between EAH intake and child BMI, eating behaviors, and parent feeding practices were examined to evaluate concurrent validity. Average intake was 63.0 ± 50.4 kcal in the classroom setting and 53.7 ± 44.6 in the individual setting, with no significant difference between settings. The intraclass correlation coefficient was 0.57, indicating moderate agreement between conditions. Overall, the EAH protocol appears to perform similarly in classroom and individual settings, suggesting the classroom protocol is a valid alternative. Future studies should further examine the role of age, sex, and weight status on eating behavior measurement paradigms.

Nondegenerate Saturation Mutagenesis: Library Construction and Analysis via MAX and ProxiMAX Randomization.

Protein engineering can enhance desirable features and improve performance outside of the natural context. Several strategies have been adopted over the years for gene diversification, and engineering of modular proteins in particular is most effective when a high-throughput, library-based approach is employed. Nondegenerate saturation mutagenesis plays a dynamic role in engineering proteins by targeting multiple codons to generate massively diverse gene libraries. Herein, we describe the nondegenerate saturation mutagenesis techniques that we have developed for contiguous (ProxiMAX) and noncontiguous (MAX) randomized codon generation to create precisely defined, diverse gene libraries, in the context of other fully nondegenerate strategies. ProxiMAX randomization comprises saturation cycling with repeated cycles of blunt-ended ligation, type IIS restriction, and PCR amplification, and is now a commercially automated process predominantly used for antibody library generation. MAX randomization encompasses a manual process of selective hybridisation between individual custom oligonucleotide mixes and a conventionally randomized template and is principally employed in the research laboratory setting, to engineer alpha helical proteins and active sites of enzymes. DNA libraries generated using either technology create high-throughput amino acid substitutions via codon randomization, to generate genetically diverse clones.

Introduction to Immunohistochemistry: From to Evolving Science to Timeless Art.

Immunohistochemistry and all techniques that use antibodies and fluorescence are widespread, essential and irreplaceable tools used in both research laboratory settings and diagnostic pathology laboratories. The field was born approximately 80years ago, with the idea that antibodies could be tagged with fluorescent substances and used to detect antigens in cells and microorganisms, and has vertiginously evolved since; these advances have come in all aspects of the methodology, tissue fixation, generation of antibodies, monoclonal antibodies, signal amplification, antigen retrieval, signal amplification, microscopy and have become increasingly sophisticated, from in situ hybridization, in situ proximity ligation assay, flow cytometry, comet assay, to multiplexing and green fluorescent protein reconstitution, yielding Nobel Prizes along the way and generating invaluable scientific and diagnostic advances as well as timeless beautiful images.