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Proteomic characterization of acidic aqueous extracts from Vicia faba L. pod valves identifies chitinase as a major co-extracted protein macromolecule.

Naturally acidic aqueous extracts from Vicia faba L. pod valves are being explored as sustainable, L-DOPA-oriented plant preparations. Pod valves represent an underutilized processing by-product reported to contain L-DOPA, a compound widely used in Parkinson's disease therapy, while acidic aqueous media may help preserve its physicochemical stability. However, the protein macromolecules co-extracted from V. faba pod valves under these conditions remain poorly characterized. This information is relevant because persistent plant proteins may influence extract composition, stability, susceptibility to degradation, and downstream processing requirements. Here, we characterized co-extracted V. faba protein macromolecules in aqueous pod-valve extracts prepared in ultrapure water or naturally acidic media, including 2% Phyllanthus emblica, 5% Punica granatum, and 2% Ribes rubrum. Protein profiles were first evaluated by SDS-PAGE and subsequently analyzed by nanoflow liquid chromatography coupled to high-resolution tandem mass spectrometry (nLC-MS/MS). Protein identifications were complemented with Gene Ontology annotation and a descriptive semi-quantitative assessment of relative protein representation across extraction media. Chitinase was the most represented V. faba-assigned protein macromolecule across the extracts, with additional highly represented proteins including glucan endo-1,3-beta-D-glucosidase, pathogenesis-related proteins, and polyphenol oxidase A1. These co-extracted proteins are mainly associated with plant defense, stress responses, cell-wall remodeling, and oxidative processing, suggesting that they may be relevant for extract quality attributes during handling and storage. This study provides a compositional proteomic reference for the co-extracted protein macromolecules present in acidic aqueous extracts from V. faba pod valves, supporting future studies on extract stability, processing optimization, and the development of standardized plant-based preparations.

Vicia faba

Selective monitoring of trace-level catechin and myricetin in herbal and aqueous matrices using magnetic MIP-DSPME: Optimization via design of experiments.

A novel dispersive solid-phase microextraction approach utilizing a magnetic molecularly imprinted polymer (MMIP) integrated with HPLC-UV detection was developed for the concurrent quantification of catechin and myricetin in herbal extracts and aqueous samples. The sorbent was engineered as a core-shell nanocomposite, consisting of a selective polymer layer deposited onto Fe3O4@SiO2-APTMS magnetic nanoparticles. Dual-template imprinting using catechin and myricetin generated complementary binding cavities within the polymer framework. Experimental variables influencing extraction were systematically screened and subsequently optimized. A Plackett-Burman design was first applied to identify the most influential factors, with pH and sorption time identified as the dominant variables. These parameters were subsequently fine-tuned using a central composite design, and the optimization process was completed in only 30 experimental runs. The sorption characteristics of the imprinted sorbent (MMIP) were compared with those of its non-imprinted counterpart (MNIP). The MMIP demonstrated markedly higher maximum binding capacities (Qmax), reaching 119.3 mg g-1 for myricetin and 112.1 mg g-1 for catechin, whereas the corresponding values for the MNIP were 32.55 and 32.08 mg g-1, respectively. Moreover, the affinity constants (KL = 0.760-0.950 L mg-1) were approximately 2.3-fold higher for the MMIP, confirming its stronger and more selective interactions with the target analytes. The selectivity coefficients for the targeted flavonoids relative to structurally related compounds, including ferulic acid, p-coumaric acid, melatonin, and curcumin, exceeded 3.5 for the MMIP, whereas the corresponding values for the MNIP were close to 1.1, demonstrating the high molecular recognition capability of the imprinted sorbent. Method validation demonstrated limits of detection (LODs) of 0.33-0.59 ng mL-1 and limits of quantification (LOQs) of 1.10-1.96 ng mL-1, and excellent linearity over the concentration range of 5.0-5500 ng mL-1 (R2 > 0.998). The method achieved recoveries of 93.96% to 105.69% with RSDs below 5.5%, while the preconcentration factors ranged from 209 to 229. Furthermore, the sorbent retained more than 95% of its extraction efficiency after four consecutive reuse cycles and more than 80% after six cycles, demonstrating excellent stability and reusability. The proposed method was successfully applied to the analysis of six medicinal plant extracts and water samples, showing negligible matrix interference and superior sensitivity, selectivity, and operational simplicity compared with conventional solid-phase extraction methods.

Flavonoids

A novel method for optimum biopsy specimen preservation for histochemical and immunohistochemical analysis.

A novel method has been developed for optimally processing biopsy specimens combining freeze-substitution with low-temperature plastic embedding. Immunohistochemistry and conventional histochemical stains were all readily performed on tissue displaying high-quality morphologic preservation. Labile antigens, especially lymphoid cell surface antigens, were well preserved. This new method avoids the need for tissue fixation and combines the superior morphologic preservation of fixed embedded tissue with the reactivity of cryostat sections. This method ensures that diagnostic information from even the smallest biopsy specimen is maximized because a wide range of phenotypic markers can be applied and evaluated in relation to high-quality morphologic preservation of tissue. Biopsy specimens are stored at room temperature without loss of tissue-specific characteristics during storage.

Acetone

Unicorn: enhancing single-cell Hi-C data with blind super-resolution for 3D genome structure reconstruction.

MOTIVATION: Single-cell Hi-C (scHi-C) data provide critical insights into chromatin interactions at individual cell levels, uncovering unique genomic 3D structures. However, scHi-C datasets are characterized by sparsity and noise, complicating efforts to accurately reconstruct high-resolution chromosomal structures. In this study, we present ScUnicorn, a novel blind super-resolution framework for scHi-C data enhancement. ScUnicorn uses an iterative degradation kernel optimization process, unlike traditional super-resolution approaches, which rely on downsampling, predefined degradation ratios, or constant assumptions about the input data to reconstruct high-resolution interaction matrices. Hence, our approach more reliably preserves critical biological patterns and minimizes noise. Additionally, we propose 3DUnicorn, a maximum likelihood algorithm that leverages the enhanced scHi-C data to infer precise 3D chromosomal structures. RESULTS: Our evaluation demonstrates that ScUnicorn achieves superior performance over the state-of-the-art methods in terms of Peak Signal-to-Noise Ratio, Structural Similarity Index Measure, and GenomeDisco scores. Moreover, 3DUnicorn's reconstructed structures align closely with experimental 3D-FISH data, underscoring its biological relevance. Together, ScUnicorn and 3DUnicorn provide a robust framework for advancing genomic research by enhancing scHi-C data fidelity and enabling accurate 3D genome structure reconstruction. AVAILABILITY AND IMPLEMENTATION: Unicorn implementation is publicly accessible at https://github.com/OluwadareLab/Unicorn.

Single-Cell Analysis

Membrane and cytosolic interleukin-1 alpha and beta in normal human epidermal cells: variability of epitope exposure in immunohistochemistry.

Previous studies have shown that interleukin-1 (IL-1) is present in normal human epidermis. However, with immunohistochemical techniques, epidermal IL-1 immunoreactivity has been found in only a limited number of epidermal cells. In the present study, we show that both IL-1 alpha and beta immunoreactivities can be detected in all epidermal cell layers, provided optimal processing of tissue samples is used. The use of isolated epidermal cells showed that keratinocytes at various stages of maturation display both membrane-associated and cytosolic IL-1 alpha and beta immunoreactivities. After protease treatment of tissue sections, the IL-1 beta immunoreactivity of the granular cell layer was enhanced by some antibodies used, whereas in the other cell layers it was clearly lower. We a) suggest a different cellular localization, processing, and/or binding to subcellular structures of IL-1 during the differentiation process of human keratinocytes and b) outline the technical difficulties in any immunohistologic approach to IL-1 status in diseased skin.

Cell Membrane

Statistical principle and methodology in the NISAN system.

The NISAN system is a new interactive statistical analysis program package constructed by an organization of Japanese statisticans. The package is widely available for both statistical situations, confirmatory analysis and exploratory analysis, and is planned to obtain statistical wisdom and to choose optimal process of statistical analysis for senior statisticians.

Computers

Phenotypic traits and regulatory role of RNA folding in molecular selection.

We concentrate on instances in which the phenotypic expression of information encoded in an RNA primary sequence might be revealed by the folding of the RNA itself. We have discovered that this situation finds concrete realization in the design of RNA molecules capable of maximizing the rate of autocatalytic synthesis when incubated with viral Q beta-replicase. This requires that we introduce the notion of phenotypic traits at the molecular level. Thus, the problem of finding RNA sequences whose phenotype favorably influences propagation amounts go finding RNA sequences which fold so as to optimize enzymatic performance and are in addition endowed with the proper recognition sites. The proof that these two problems are indeed equivalent has two steps: First we predict the metastable folded structures formed as a template RNA chain grows by sequential incorporation of nucleotides. The transient folded states appear to be involved in the regulation of the enzyme activity and they occur in a manner which is "oblivious" of thermodynamic time scales. Secondly, we compute the time-dependent activation energy for relaxation of each intermediate structure. This is done to establish constraints necessary for optimization of the regulatory role of RNA folding. The search for prospective template sequences is subject to such constraints. Our results aim at elucidating an optimization process realized by molecular selection in de novo (template-free) RNA synthesis by Q beta-replicase. We argue that the phenotype which mediates selection is given by metastable folding which emerges together with the printing of the genotype, that is, within the time span of a replication turnover.

Algorithms

Induced pluripotent stem cell reprogramming: methodological evolution and challenges in clinical translation.

Cell reprogramming can transform somatic cells into induced pluripotent stem cells providing a platform for patient-specific disease modeling, drug screening and regenerative medicine research. Since the advent of OKSM-mediated reprogramming, the system of technical approaches has evolved continuously - from integrated viral vectors to non-integrated episomal systems and, more recently, chemical reprogramming and CRISPR approaches. The simultaneous advances in single-cell multi-omics, biomaterials engineering, and artificial intelligence have further refined the controllability and precision of the reprogramming process. Despite these innovations, problems persist that hinder clinical translation: incomplete epigenetic resetting, ongoing clonal heterogeneity, genomic instability in long-term culture, and the lack of standardized Good Manufacturing Practice protocols for large-scale manufacturing. This review summarizes the trajectory of iPSC reprogramming technologies, with special emphasis on the translational applicability of each modality. We evaluated viral and nonviral delivery systems, chemical reprogramming, strategies that aid gene editing, and emerging engineering platforms, including microfluidics, smart biomaterials, and artificial-intelligence-driven process optimization. We further identify the core "translational triltrilas", namely, the inherent tradeoffs between security, homogeneity, and scalability, and propose a comprehensive strategy to overcome these bottlenecks. By linking basic mechanistic understandings with industrial and regulatory considerations, this review aims to provide a route for transitioning iPSC technology from a laboratory tool to a clinically viable manufacturing platform.

clinical translation

Marine endophytes: biosynthetic engines for novel bioactive metabolites.

Marine endophytes are prolific sources of structurally diverse secondary metabolites with significant pharmaceutical potential, including anticancer, antimicrobial, and antioxidant agents. However, their commercial utilization is hindered by genomic instability in axenic cultures and inconsistent metabolite yields. While current studies focus on symbiotic interactions and compound discover, critical gaps persist in harnessing their biosynthetic capabilities. This review synthesizes knowledge on marine fungal metabolites and proposes a paradigm shift toward resource-driven research. It addresses strain improvement limitations and suggests strategies like mutagenesis, protoplast fusion, and metabolic engineering to bolster production stability and efficiency. The paper also discusses biological process optimization, including fermentation tuning, inducer and precursor addition, and adsorbent use, to enhance natural product synthesis. By identifying these research gaps and proposing a strategic roadmap, the review advances the stable and scalable production of bioactive metabolites, unlocking the commercial and therapeutic potential of marine endophytic fungi.

bioactive metabolites

Patients who amplify bodily sensations.

Patients troubled by symptoms, regardless of the degree of demonstrable disease, are subject to fources that cause them to amplify, focus upon, and worry about these bodily perceptions. These forces are psychological, sociocultural, or part of the medical care process. Optimal management of the symptomatic and somatizing patient thus entails obtaining psychological information about emotional precipitants, relevant childhood experiences, psychiatric disorders, and the personal meaning of the symptom; searching for the somatizing personality themes of masochism and guilt, hostility, and dependence; understanding the patient's goals in obtaining medical care, such as information and explanation, psychological counseling, or social and administrative intervention; and assessing situational stress, secondary gain, and ethnic and cultural forces that foster the amplification of physical symptoms.

Anxiety

Strategies for automated sequencing of human mitochondrial DNA directly from PCR products.

A rapid, robust and sensitive method has been developed for the amplification and direct sequencing of human mitochondrial DNA. A 403-bp hypervariable segment was amplified by two successive rounds of nested PCR. This was then sequenced by the dideoxy chain termination method using dye-labeled universal sequencing primers in conjunction with an automated DNA sequencer. This paper describes the assessment of four different strategies for this amplification and sequencing process. Optimal results were obtained by immobilizing the biotinylated PCR product on Dynabeads followed by solid-phase sequencing with Sequenase. Degraded samples and those containing trace amounts of DNA such as extracts from hair shafts can be analyzed by this method.

Automation

Suspension culture of mammalian cells.

Mammalian cell suspension culture systems are being used increasingly in the biotechnology industry. This is due to their many advantages including simplicity and homogeneity of culture. Suspension systems are very adaptable (e.g., for microcarrier, microencapsulation, or other methods of culture). Their engineering is thoroughly understood and standardized at large scale, and automation and cleaning procedures are well established. Suspension systems offer the possibility of quick implementation of production protocols due to their ability to be scaled easily once the basic culture parameters are understood. The only main disadvantage of the suspension culture systems to date is their inapplicability for the production of human vaccines from either primary cell lines or from normal human diploid cell lines (Hayflick et al., 1987 and references therein). One of the great advantages of suspension culture is the opportunity it provides to study interactions of metabolic and production phenomena in chemostat or turbidostat steady-state systems. Furthermore, in suspension culture systems from which cell number and cell mass measurements are easy to obtain, rigorous and quantitative estimations of the effects of growth conditions or perturbations of metabolic homeostasis can be made. Such studies can speed up the development of optimal processes. With our increasing understanding of factors influencing expression in mammalian cells (Cohen and Levinson, 1988; Santoro et al., 1988) and the direct application of new methods in suspension culture (Rhodes and Birch, 1988), its usefulness and importance is likely to increase in the future. In this chapter, we have described some of the potential uses of the various suspension culture systems and have covered most of the established technology and literature. Due to the rapid developments and needs in the biotechnology industry and the versatility of suspension culture systems, it is probable that many more variations on this theme will evolve in the near future at both the pilot and production scales.

Animals

[Optimization of immobilization conditions for acid proteinase from Aspergillus awamori].

To optimize the immobilization conditions for acid proteinase from Aspergillus awamori by covalent binding through glutaraldehyde, experiments were carried out using the Box-Wilson method. The optimization process was assessed on the basis of absolute activity A, coefficient of activity retention gamma and their product A gamma. The following conditions can be recommended: glutaraldehyde concentration 50--60 mg/g, enzyme concentration not less than 40 mg/g, time of glutaraldehyde treatment 2--2.5 hrs, immobilization time 2 hrs, pH about 4.0, and temperature 35--40 degrees C. Under these conditions A=220--230 U/g, gamma = 23--24% Agamma = 5,000--6,000.

Aspergillus

Optimal temperature control policy for a two-stage recombinant fermentation process.

The optimal temperature control policy to be followed in the operation of a two-stage fermentation system in which gene expression is induced by a temperature-sensitive gene switching system was studied. A genetically structured model was used to describe product formation, and kinetic equations based on experimental data were used to quantify the specific gene expression rate and parameters that affect plasmid instability. A constant temperature control policy and temperature profiling control policy including temperature cycling were studied and compared. Maximum average production rate was obtained from a temperature control policy in which the second stage was operated initially at about 40.5 degrees C and the temperature decreased slightly to a constant value at 40.0 degrees C. The maximum average production rate, which corresponds to the optimal temperature control policy, for an operation of 180 h was 29.7 units of protein (mg of cells)-1 h-1.

DNA, Recombinant

Effects of optimization and image processing in digital chest radiography: an ROC study with an anthropomorphic phantom.

A digital system for chest radiography based on a large image intensifier was compared to a conventional film-screen system. The digital system was optimized with regard to spatial and contrast resolution and dose. The images were digitally processed for contrast and edge enhancement. A simulated pneumothorax and two simulated nodules were positioned over the lungs and the mediastinum of an anthropomorphic phantom. Observer performance was evaluated with ROC analysis. Five observers assessed the processed digital images and the conventional full-size radiographs. The time spent viewing the full-size radiographs and the digital images was recorded. For the simulated pneumothorax, the results showed perfect performance for the full-size radiographs and detectability was high also for the processed digital images. No significant difference in the detectability of the simulated nodules was seen between the two imaging systems. The results for the digital images showed a significantly improved detectability for the nodules in the mediastinum as compared to a previous ROC study where no optimization and image processing was available. No significant difference in detectability was seen between the former and the present ROC study for small nodules in the lung. No difference was seen in the time spent assessing the conventional full-size radiographs and the digital images. The study indicates that processed digital images produced by a large image intensifier are equal in image quality to conventional full-size radiographs for low-contrast objects such as nodules.

Evaluation Studies as Topic

[Principles for optimizing and guaging several processes in the technology of vaccine production. I. Several problems in guaging and optimizing thermal sterilization of fluids].

Thermal sterilization of fluids--one of the widespread operations in microbiological laboratories and in vaccine production--solves two tasks: provides sterility and maximal preservation of biological value of the sterilized fluid. A possibility and expediency of using some indices for the quantitative assessment of the efficacy of the sterilization regimens, including measurement of the sterilization processes is considered in this work. A possible way of the regimen optimization on the basis of known values of the activation energies of the processes of decomposition of thermolabile components and inactivation of foreign microbial flora is assessed.

Hot Temperature

Optimization of a process for the production of (R)-2-hydroxy-4-phenylbutyric acid--an intermediate for inhibitors of angiotensin converting enzyme.

(R)-2-Hydroxy-4-phenylbutyric acid, an intermediate in the manufacture of inhibitors of angiotensin converting enzyme, can be produced continuously in an enzyme membrane reactor by enzymatic reduction of its corresponding alpha-keto acid. D-Lactate dehydrogenase (D-LDH) from Staphylococcus epidermidis was chosen as the most appropriate enzyme to carry out the NADH-dependent reduction. Formate dehydrogenase (FDH) was used for NADH regeneration. Detailed kinetic measurements and a mathematical model for the coupled enzyme reactions were applied to calculate the optimal conditions for continuous production of the alpha-hydroxy acid. A mass of 1 kg [corrected] (R)-2-hydroxy-4-phenylbutyric acid was synthesized in a 220 ml enzyme membrane reactor over a period of 4 weeks. A mean space-time-yield of 165 g l-1 d-1 was achieved at low enzyme consumptions of 150 U kg-1 alpha-hydroxy acid for FDH and D-LDH.

Angiotensin-Converting Enzyme Inhibitors

The role of glucocorticoid hormones as biological amplifiers.

Recent research in hormone action has been aimed at studying single effects in well-defined systems. As exemplified in several chapters of this book, it has been possible to deduce a general mechanism of action of the glucocorticoids using this approach. Most hormones, and the glucocorticoids in particular, do not act as independent agents in the intact animal. Although the best known example of how glucocorticoids interact with other hormones is the amplification of the effect of those whose action is mediated by cAMP, these steroids also augment the effects of a variety of other hormones and effectors. Such interactions are of interest in clinical medicine as well, since glucocorticoid hormones are used in combination with other drugs in a number of conditions, including the treatment of asthma, allergies, and certain kinds of shock and cancer. Neither the biochemical nor the pharmacologic basis for the effects of the glucocorticoids is known. In some cases the actions of other hormones are not observed unless the tissue has first been exposed to glucocorticoids. In these instances the glucocorticoids are said to exert a "permissive effect," since they allow a process to proceed at a maximal rate even though the steroid itself has no effect on this process. There is no doubt that such examples exist, as documented above: thus the concept of a "permissive effect" does have utility. The term fails to describe the more general role the glucocorticoids play, since in many instances the steroid also has a direct effect on the process itself, or optimizes a process in which the primary effector is not as yet known. Because of these cases, and because the historically more general usage first proposed by INGLE [1] seems to have been forgotten, use of the term "permissive effect" has been avoided in this chapter. An ultimate goal in glucocorticoid hormone research is to identify the mechanisms involved in the amplification effect these hormones exert. Now that the actions of these hormones and of the hormones they interact with are being defined, such work is within the realm of feasibility.

Animals