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Simple Summary: Cancer is one of the leading causes of death, with one out of six deaths worldwide. Breast cancer has the highest occurrence of other cancers, although, in terms of the number of deaths, breast cancer ranks fifth among all cancers. Depending on the nature of the cells and the associated cellular environment, different types of breast cancer are possible. Many breast cancer types are highly challenging to treat, and even if treatable, the treatments involve several side effects. Antibody–drug conjugates (ADCs) comprise monoclonal antibodies that explicitly target the tumor-specific antigens and cytotoxic drugs (mainly small molecules) that act as payloads to kill the malignant cells/tumor. As a result, the healthy cells are not affected by the toxic drugs, which potentially reduces the side effects. These target-specific chemo-biologic drugs (ADCs) have shed new light on hopes in cancer therapy. Currently, three ADCs have been approved for breast cancer treatment, and many are in clinical trials. A detailed discussion on the biochemical nature, mechanism of action, and current status of ADCs in breast cancer treatments has been accomplished in this article. While we made every effort to include all the related developments in this field, any omission is truly unintentional. Cancer is a significant health challenge globally, with millions of people affected every year, resulting in high morbidity and mortality. Although other treatment options are available with limitations, chemotherapy, either standalone or combined with other therapeutic procedures, is the most commonly used practice of treating cancer. In chemotherapy, cancer cells/malignant tumors are targeted; however, due to less target specificity, along with malignant cells, normal cells are also affected, which leads to various off-target effects (side effects) that impact the patient quality of life. Out of all the different types of cancers, breast cancer is the most common type of cancer in humans worldwide. Current anticancer drug discovery research aims to develop therapeutics with higher potency and lower toxicity, which is only possible through target-specific therapy. Antibody–drug conjugates (ADCs) are explicitly designed to target malignant tumors and minimize off-target effects by reducing systemic cytotoxicity. Several ADCs have been approved for clinical use and have shown moderate to good efficacy so far. Considering various aspects, chemotherapy and ADCs are useful in treating cancer. However, ADCs provide a more focused and less toxic approach, which is especially helpful in cases where resistance to chemotherapy (drug resistance) occurs and in the type of malignancies in which specific antigens are overexpressed. Ongoing ADC research aims to develop more target-specific cancer treatments. In short, this study presents a concise overview of ADCs specific to breast cancer treatment. This study provides insight into the classifications, mechanisms of action, structural aspects, and clinical trial phases (current status) of these chemo-biologic drugs (ADCs). [ABSTRACT FROM AUTHOR]

Many proteins undergo a post-translational lipid attachment, which increases their hydrophobicity, thus strengthening their membrane association properties or aiding in protein interactions. Geranylgeranyltransferase-I (GGTase-I) is an enzyme involved in a 3-step post-translational modification (PTM) pathway that attaches a 20-carbon lipid group called geranylgeranyl at the carboxy-terminal cysteine of proteins ending in a canonical CaaL motif (C—cysteine, a—aliphatic, L—often leucine, but can be phenylalanine, isoleucine, methionine, or valine). Genetic approaches involving 2 distinct reporters were employed in this study to assess Saccharomyces cerevisiae GGTase-I specificity, for which limited data exist, toward all 8,000 CXXX combinations. Orthogonal biochemical analyses and structure-based alignments were also performed to better understand the features required for optimal target interaction. These approaches indicate that yeast GGTase-I best modifies the Cxa[L/F/I/M/V] sequence that resembles but is not an exact match for the canonical CaaL motif. We also observed that minor modification of noncanonical sequences is possible. A consistent feature associated with well-modified sequences was the presence of a nonpolar a2 residue and a hydrophobic terminal residue, which are features recognized by mammalian GGTase-I. These results thus support that mammalian and yeast GGTase-I exhibit considerable shared specificity. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) serve as messengers for intercellular communication, yet the precise mechanisms by which recipient cells interpret EV messages remain incompletely understood. In this study, we explored how the origin of EVs, their protein cargo, and the recipient cell type influence the cellular response to EVs within an embryo implantation model. We treated two types of EVs to 6 different recipient cell types and expression of zinc finger protein 81 (ZNF81) gene expression in the recipient cells were quantified using quantitative polymerase chain reaction (qPCR). The proteomic contents of the EV cargos were also analyzed. The results showed that downregulation of the ZNF81 gene was a specific cellular response of receptive endometrial epithelial cells to trophoblast derived EVs. Protein cargo analysis revealed that the proteomic profile of EVs depends on their cell of origin and therefore may affect the recipient cell response to EVs. Furthermore, trophoblastic EVs were found to be specifically enriched with transcription factors such as CTNNB1 (catenin beta-1), HDAC2 (histone deacetylase 2), and NOTCH1 (neurogenic locus notch homolog protein 1), which are known regulators of ZNF81 gene expression. The current study provided compelling evidence supporting the existence of EV specificity, where the characteristics of both the EVs and the recipient cell type collectively contribute to regulating EV target specificity. Additionally, EV protein cargo analysis suggested a potential association between transcription factors and the specific functionality of trophoblastic EVs. This in vitro embryo implantation model and ZNF81 read-out provides a unique platform to study EV specific functionality in natural cell-cell communication.

Context: The Felixer grooming device ('Felixer') is a lethal method of feral cat control designed to be cost-effective and target specific. Aims: This study aims to test the target specificity of the Felixer in Tasmania, with a particular focus on Tasmanian devil and quoll species due to the overlap in size, habitats and behaviour between these native carnivores and feral cats. Methods: Our study deployed Felixer devices set in a non-lethal mode in nine field sites in Tasmania, one field site in New South Wales and two Tasmanian wildlife sanctuaries. Key results: Our study recorded 4376 passes by identifiable vertebrate species including 528 Tasmanian devil passes, 507 spotted-tailed quoll passes and 154 eastern quoll passes. Our data showed that the Felixer can successfully differentiate quoll species from feral cats with spotted-tailed quolls and eastern quolls targeted in 0.19% and 0% of passes, respectively. However, Tasmanian devils and common wombats were targeted in 23.10% and 12% of passes, respectively, although sample size was low for common wombats (n = 25). Conclusions: The Felixer could not reliably identify Tasmanian devils and possibly common wombats as non-target species. Further data is needed to confirm the potential for impacts on the common wombat and other potential non-target species in Tasmania, and the likelihood of the toxin being ingested by falsely targeted individuals. Implications: Our study suggest that the Felixer device is safe for use in the presence of two species of conservation concern, the eastern and spotted-tailed quoll. It also supports evidence from previous studies that the Felixer is unlikely to impact bettongs and potoroos. Use of Felixer devices across much of Tasmania would have to balance the conservation or economic benefits of cat control against potential impacts on Tasmanian devils. We suggest that active Felixer deployments be preceded by surveys to establish the range of species present at the control site, and the season of control considered carefully to minimise potential impacts on more susceptible juvenile animals. In addition, modifications to the Felixer device such as the proposed incorporation of AI technology should be tested against the Tasmanian devil and other non-target species. Feral cats present an alarming threat to Australia's native biodiversity. The Felixer grooming device is a method of feral cat control that is designed to be target-specific and efficient in the control of this invasive species. In order for the Felixer to be considered as a feral cat control device in Tasmania, its effectiveness in differentiating cats from similar carnivores, specifically Tasmanian devils and quolls, needs to be tested. Photograph by Darren Rumble. [ABSTRACT FROM AUTHOR]

Objective: Despite the development of several vaccines against severe acute respiratory syndrome coronavirus-2, the need for an additional prophylactic agent is evident. In recent in silico studies, isovitexin exhibited a higher binding affinity against the human angiotensin converting-enzyme 2 (hACE2) receptor than existing antiviral drugs. The research aimed to find out the point specificity of isovitexin for the hACE2 receptor and to assess its therapeutic potential, depending on the stability of the isovitexin–hACE2 complex. Materials and Methods: The pharmacokinetic profile of isovitexin was analyzed. The crystal structure of the hACE2 receptor and the ligand isovitexin were docked to form a ligand-protein complex following molecular optimization. To determine the isovitexin–hACE2 complex stability, their binding affinity, hydrogen bonding, and hydrophobic interactions were studied. Lastly, the root mean square deviation (RMSD), root mean square fluctuation, solvent accessible surface area, molecular surface area, radius of gyration (Rg), polar surface area, and principal component analysis values were found by simulating the complex with molecular dynamic (MD). Results: The predicted Lethal dose50 for isovitexin was 2.56 mol/kg, with an acceptable maximum tolerated dose and no hepatotoxicity or AMES toxicity. Interactions with the amino acid residues Thr371, Asp367, Glu406, Pro346, His345, Phe274, Tyr515, Glu375, Thr347, Glu402, and His374 of the hACE2 protein were required for the high binding affinity and specificity of isovitexin. Based on what was learned from the MD simulation, the hACE2 receptor-blocking properties of isovi¬texin were looked at. Conclusions: Isovitexin is a phytochemical with a reasonable bioactivity and safety profile for use in humans, and it can potentially be used as a hACE2-specific therapeutic to inhibit COVID-19 infection. [J Adv Vet Anim Res 2022; 9(2.000): 230-240]

SUMMARY: Sacred lotus (Nelumbo nucifera Gaertn.) is a basal eudicot plant with a unique lifestyle, physiological features, and evolutionary characteristics. Here we report the unique profile of transposable elements (TEs) in the genome, using a manually curated repeat library. TEs account for 59% of the genome, and hAT (Ac/Ds) elements alone represent 8%, more than in any other known plant genome. About 18% of the lotus genome is comprised of Copia LTR retrotransposons, and over 25% of them are associated with non‐canonical termini (non‐TGCA). Such high abundance of non‐canonical LTR retrotransposons has not been reported for any other organism. TEs are very abundant in genic regions, with retrotransposons enriched in introns and DNA transposons primarily in flanking regions of genes. The recent insertion of TEs in introns has led to significant intron size expansion, with a total of 200 Mb in the 28 455 genes. This is accompanied by declining TE activity in intergenic regions, suggesting distinct control efficacy of TE amplification in different genomic compartments. Despite the prevalence of TEs in genic regions, some genes are associated with fewer TEs, such as those involved in fruit ripening and stress responses. Other genes are enriched with TEs, and genes in epigenetic pathways are the most associated with TEs in introns, indicating a dynamic interaction between TEs and the host surveillance machinery. The dramatic differential abundance of TEs with genes involved in different biological processes as well as the variation of target preference of different TEs suggests the composition and activity of TEs influence the path of evolution. Significance Statement: We demonstrate that DNA transposons amplified more substantially than retrotransposons in sacred lotus (Nelumbo nucifera Gaertn.), and retrotransposons are enriched in introns more than in any other regions in the genome. Furthermore, we demonstrate that different genomic compartments are associated with distinct amplification/retention dynamics. Most importantly, we show that different superfamilies of transposons are preferentially inserted into genes involved in different biological processes; hence, the composition and activity of transposons could determine the path of evolution of protein‐coding genes. [ABSTRACT FROM AUTHOR]

Circuit formation is a defining characteristic of the developing brain. However, multiple lines of evidence suggest that circuit formation can also take place in adults, the mechanisms of which remain poorly understood. Here, we investigated the epilepsy-associated mossy fiber (MF) sprouting in the adult hippocampus and asked which cell surface molecules define its target specificity. Using single-cell RNAseq data, we found lack and expression of Pcdh11x in non-sprouting and sprouting neurons respectively. Subsequently, we used CRISPR/Cas9 genome editing to disrupt the Pcdh11x gene and characterized its consequences on sprouting. Although MF sprouting still developed, its target specificity was altered. New synapses were frequently formed on granule cell somata in addition to dendrites. Our findings shed light onto a key molecular determinant of target specificity in MF sprouting and contribute to understanding the molecular mechanism of adult brain rewiring. [ABSTRACT FROM AUTHOR]

Mammalian visual functions rely on distributed processing across interconnected cortical and subcortical regions. In higher-order visual areas (HVAs), visual features are processed in specialized streams that integrate feedforward and higher-order inputs from intracortical and thalamocortical pathways. However, the precise circuit organization responsible for HVA specialization remains unclear. We investigated the cellular architecture of primary visual cortex (V1) and higher-order visual pathways in the mouse, focusing on their roles in shaping visual representations. Using in vivo functional imaging and neural circuit tracing, we found that HVAs preferentially receive inputs from both V1 and higher-order pathways tuned to similar spatiotemporal properties, with the strongest selectivity seen in layer 2/3 neurons. These neurons exhibit target-specific tuning and sublaminar specificity in their projections, reflecting cell-type-specific visual information flow. In contrast, HVA layer 5 pathways nonspecifically broadcast visual signals across cortical areas, suggesting a role in distributing HVA outputs. Additionally, thalamocortical pathways from the lateral posterior thalamic nucleus (LP) provide highly specific, nearly non-overlapping visual inputs to HVAs, complementing intracortical inputs and contributing to input functional diversity. Our findings suggest that the convergence of laminar and cell-type-specific pathways V1 and higher-order intracortical and thalamocortical pathways plays a key role in shaping the functional specialization and diversity of HVAs., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objective: Despite the development of several vaccines against severe acute respiratory syndrome coronavirus-2, the need for an additional prophylactic agent is evident. In recent in silico studies, isovitexin exhibited a higher binding affinity against the human angiotensin converting-enzyme 2 (hACE2) receptor than existing antiviral drugs. The research aimed to find out the point specificity of isovitexin for the hACE2 receptor and to assess its therapeutic potential, depending on the stability of the isovitexin-hACE2 complex. Materials and Methods: The pharmacokinetic profile of isovitexin was analyzed. The crystal structure of the hACE2 receptor and the ligand isovitexin were docked to form a ligand-protein complex following molecular optimization. To determine the isovitexin-hACE2 complex stability, their binding affinity, hydrogen bonding, and hydrophobic interactions were studied. Lastly, the root mean square deviation (RMSD), root mean square fluctuation, solvent accessible surface area, molecular surface area, radius of gyration (Rg), polar surface area, and principal component analysis values were found by simulating the complex with molecular dynamic (MD). Results: The predicted Lethal dose50 for isovitexin was 2.56 mol/kg, with an acceptable maximum tolerated dose and no hepatotoxicity or AMES toxicity. Interactions with the amino acid residues Thr371, Asp367, Glu406, Pro346, His345, Phe274, Tyr515, Glu375, Thr347, Glu402, and His374 of the hACE2 protein were required for the high binding affinity and specificity of isovitexin. Based on what was learned from the MD simulation, the hACE2 receptor-blocking properties of isovitexin were looked at. Conclusions: Isovitexin is a phytochemical with a reasonable bioactivity and safety profile for use in humans, and it can potentially be used as a hACE2-specific therapeutic to inhibit COVID-19 infection. [ABSTRACT FROM AUTHOR]

The constantly expanding group of class II CRISPR-Cas (clustered regularly interspaced short palindromic repeats-associated) effectors and their engineered variants exhibit distinct editing modes and efficiency, fidelity, target range, and molecular size. Their enormous diversity of capabilities provides a formidable toolkit for a large array of technologies. We review the structural and biochemical mechanisms of versatile effector proteins from class II CRISPR-Cas systems to provide mechanistic insights into their target specificity, protospacer adjacent motif (PAM) restriction, and activity regulation, and discuss possible strategies to enhance genome-engineering tools in terms of accuracy, efficiency, applicability, and controllability. The enormous diversity of capabilities for the constantly expanding group of class II CRISPR-Cas (clustered regularly interspaced short palindromic repeats-associated) effectors and their engineered variants offers a formidable toolkit for a large array of technologies. The mechanisms of substrate recognition and cleavage, target specificity, protospacer adjacent motif (PAM) restriction, and activity regulation of versatile effector proteins from class II CRISPR-Cas systems are summarized and compared. Strategies are explored to enhance genome-engineering tools in terms of accuracy, efficiency, applicability, and controllability. [ABSTRACT FROM AUTHOR]

cGMP interactors play a role in several pathologies and may be targets for cGMP analog‐based drugs, but the success of targeting depends on the biochemical stereospecificity between the cGMP‐analog and the interactor. The stereospecificity between general cGMP analogs—or such that are selectivity‐modified to obtain, for example, inhibitory actions on a specific target, like the cGMP‐dependent protein kinase—have previously been investigated. However, the importance of stereospecificity for cGMP‐analog binding to interactors is not known. We, therefore, applied affinity chromatography on mouse cortex proteins utilizing analogs with cyclic phosphate (8‐AET‐cGMP, 2‐AH‐cGMP, 2′‐AHC‐cGMP) and selectivity‐modified analogs with sulfur‐containing cyclic phosphorothioates (Rp/Sp‐8‐AET‐cGMPS, Rp/Sp‐2′‐AHC‐cGMPS) immobilized to agaroses. The results illustrate the cGMP analogs' stereospecific binding for PKG, PKA regulatory subunits and PKA catalytic subunits, PDEs, and EPAC2 and the involvement of these in various KEGG pathways. For the seven agaroses, PKG, PKA regulatory subunits, and PKA catalytic subunits were more prone to be enriched by 2‐AH‐, 8‐AET‐, Rp‐8‐AET‐, and Sp‐8‐AET‐cGMP, whereas PDEs and EPAC2 were more likely to be enriched by 2‐AH‐, Rp‐2′‐AHC‐, and Rp‐8‐AET‐cGMP. Our findings help elucidate the stereospecific‐binding sites essential for the interaction between individual cGMP analogs and cGMP‐binding proteins, as well as the cGMP analogs' target specificity, which are two crucial parameters in drug design. [ABSTRACT FROM AUTHOR]

Many proteins undergo a post-translational lipid attachment, which increases their hydrophobicity, thus strengthening their membrane association properties or aiding in protein interactions. Geranylgeranyltransferase-I (GGTase-I) is an enzyme involved in a 3-step post-translational modification (PTM) pathway that attaches a 20-carbon lipid group called geranylgeranyl at the carboxy-terminal cysteine of proteins ending in a canonical CaaL motif (C-cysteine, a-aliphatic, L-often leucine, but can be phenylalanine, isoleucine, methionine, or valine). Genetic approaches involving 2 distinct reporters were employed in this study to assess Saccharomyces cerevisiae GGTase-I specificity, for which limited data exist, toward all 8,000 CXXX combinations. Orthogonal biochemical analyses and structure-based alignments were also performed to better understand the features required for optimal target interaction. These approaches indicate that yeast GGTase-I best modifies the Cxa[L/F/I/M/V] sequence that resembles but is not an exact match for the canonical CaaL motif. We also observed that minor modification of noncanonical sequences is possible. A consistent feature associated with well-modified sequences was the presence of a nonpolar a2 residue and a hydrophobic terminal residue, which are features recognized by mammalian GGTase-I. These results thus support that mammalian and yeast GGTase-I exhibit considerable shared specificity., Competing Interests: Conflicts of interest The author(s) declare no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Genetics Society of America.)

Extracellular vesicles (EVs) serve as messengers for intercellular communication, yet the precise mechanisms by which recipient cells interpret EV messages remain incompletely understood. In this study, we explored how the origin of EVs, their protein cargo, and the recipient cell type influence the cellular response to EVs within an embryo implantation model. We treated two types of EVs to 6 different recipient cell types and expression of zinc finger protein 81 (ZNF81) gene expression in the recipient cells were quantified using quantitative polymerase chain reaction (qPCR). The proteomic contents of the EV cargos were also analyzed. The results showed that downregulation of the ZNF81 gene was a specific cellular response of receptive endometrial epithelial cells to trophoblast derived EVs. Protein cargo analysis revealed that the proteomic profile of EVs depends on their cell of origin and therefore may affect the recipient cell response to EVs. Furthermore, trophoblastic EVs were found to be specifically enriched with transcription factors such as CTNNB1 (catenin beta-1), HDAC2 (histone deacetylase 2), and NOTCH1 (neurogenic locus notch homolog protein 1), which are known regulators of ZNF81 gene expression. The current study provided compelling evidence supporting the existence of EV specificity, where the characteristics of both the EVs and the recipient cell type collectively contribute to regulating EV target specificity. Additionally, EV protein cargo analysis suggested a potential association between transcription factors and the specific functionality of trophoblastic EVs. This in vitro embryo implantation model and ZNF81 read-out provides a unique platform to study EV specific functionality in natural cell-cell communication., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Dissanayake, Godakumara, Muhandiram, Kodithuwakku and Fazeli.)

Lassa hemorrhagic fever, caused by Lassa mammarenavirus (LASV) infection, accumulates up to 5000 deaths every year. Currently, there is no vaccine available to combat this disease. In this study, a library of 200 bioactive compounds was virtually screened to study their drug-likeness with the capacity to block the α-dystroglycan (α- DG) receptor and prevent LASV influx. Following rigorous absorption, distribution, metabolism, and excretion (ADME) and quantitative structure-activity relationship (QSAR) profiling, molecular docking was conducted with the top ligands against the α-DG receptor. The compounds chrysin, reticuline, and 3-caffeoylshikimic acid emerged as the top three ligands in terms of binding affinity. Post-docking analysis revealed that interactions with Arg76, Asn224, Ser259, and Lys302 amino acid residues of the receptor protein were important for the optimum binding affinity of ligands. Molecular dynamics simulation was performed comprehensively to study the stability of the protein-ligand complexes. In-depth assessment of root-mean-square deviation (RMSD), root mean square fluctuation (RMSF), polar surface area (PSA), B-Factor, radius of gyration (Rg), solvent accessible surface area (SASA), and molecular surface area (MolSA) values of the protein-ligand complexes affirmed that the candidates with the best binding affinity formed the most stable protein-ligand complexes. To authenticate the potentialities of the ligands as target-specific drugs, an in vivo study is underway in real time as the continuation of the research. [ABSTRACT FROM AUTHOR]

Natural occurring molecules often represent an interesting starting point for the development of novel greener solvents. Currently, as a result of centuries compiling information about these molecules, we have a vast library of promising raw materials. Natural deep eutectic systems (NADES) are mostly composed by natural primary metabolites such as sugars, sugar alcohols, organic acids, amino acids, and amines, but can also be formed with secondary metabolites such as terpenes and vanillin, or biopolymers. Moreover, NADES have been described as antibacterial and antibiofilm, antifungal, anticancer, antioxidant and wound healing agents. The tailor-made versatility and its compliance with the green chemistry metrics, have pushed forward the possible therapeutic role of these eutectic systems. In this chapter we aim to challenge the community to join the discussion on what we consider to be the next step in these systems comprehension-target-specificity. We already have evidences of its therapeutic role, so questions such as: does these systems work intra or extra cellularly? How do they interact with cellular membranes? Do they have an impact on gene expression? Are of most relevance to fulfill NADES potential as therapeutic agents. Furthermore, considering the current pursue for sustainability, the greenness and biosafety of NADES is briefly addressed coupling the major advances of eutectics as therapeutic agents with its promising contribution as an alternative to the industrial status quo. [ABSTRACT FROM AUTHOR]

Biological imaging and sensing are vital for understanding the biochemical and biological processes related to drug discovery and development. Nano-quantum sensors such as quantum dots and fluorescent nanodiamonds are luminescent nanoparticle sensors with excellent optical properties originating from quantum effects, and these sensors are promising for long-term imaging and physicochemical sensing with high spatiotemporal resolution. However, owing to the requirements of biological compatibility and target specificity for such sensor applications, modifying the sensor surfaces is essential. Moreover, owing to the demand for imaging- and sensing-assisted therapies (theranostics), a combination of nano-quantum sensors and therapeutic agents has been developed via surface modifications. We herein outline advanced surface modifications of nano-quantum sensors and their applications in in vitro and in vivo imaging, sensing, and therapy for target-based drug discovery and development. • Various chemical reaction routes are available for modifying nano-quantum sensor surfaces. • Nano-quantum sensors enable long-term imaging and sensing for probing biological and biochemical processes. • A combination of nano-quantum sensors and therapeutic agents plays a vital role in imaging- and sensing-assisted therapy. [ABSTRACT FROM AUTHOR]

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease, progressively distinctive via cartilage destruction, auto-antibody production, severe joint pain, and synovial inflammation. Nanotechnology represents as one of the utmost promising scientific technologies of the 21st century. It exhibits remarkable potential in the field of medicine, including imaging techniques and diagnostic tools, drug delivery systems and providing advances in treatment of several diseases with nanosized structures (less than 100 nm)., Objective: Conventional drugs as a cornerstone of RA management including disease-modifying antirheumatic drugs (DMARDS), Glucocorticosteroids, etc are under clinical practice. Nevertheless, their low solubility profile, poor pharmacokinetics behaviour, and non-targeted distribution not only hamper their effectiveness, but also give rise to severe adverse effects which leads to the need for the emergence of nanoscale drug delivery systems., Methods: Several types of nano-diagnostic agents and nanocarriers have been identified; including polymeric nanoparticles (NPs), liposomes, nanogels, metallic NPs, nanofibres, carbon nanotubes, nano fullerene etc. Various patents and clinical trial data have been reported in relevance to RA treatment., Results: Nanocarriers, unlike standard medications, encapsulate molecules with high drug loading efficacy and avoid drug leakage and burst release before reaching the inflamed sites. Because of its enhanced targeting specificity with the ability to solubilise hydrophobic drugs, it acts as an enhanced drug delivery system., Conclusion: This study explores nanoparticles potential role in RA as a carrier for site-specific delivery and its promising strategies to overcome the drawbacks. Hence, it concludes that nanomedicine is advantageous compared with conventional therapy to enhanced futuristic approach., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Abstract Magnetic nanoparticles (MNPs) are promising candidates for drug delivery and treatment of various disorders. Toxicity evaluation is a critical point in the development of nanoformulations and therefore, draws considerable attention. Formulations involving individual or combinatorial nanoparticle suspensions might be used for targeted delivery and treatment. This might be a evaluated further for safety related issues considering future medications based on MNPs. Nanoparticle distribution in the body is dependent on its surface characteristics. Size, dose and routes of nanoparticle entry have to be taken into consideration for future assays. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Highlights • CRISPR/Cas9 off-target effects (OTEs) can confound interpretation of results. • Considerations on picking proper host cells and genes for CRISPR editing discussed. • Mitigation of OTEs via gRNA design and controlled exposure of Cas9/gRNAs discussed. • Approaches on controlling CRISPR OTEs and biological variations discussed. • Strategies discussed here applicable to all genome editing experiments. Abstract The CRISPR/Cas9 system has enabled efficient modification of genes in a variety of cellular systems for studying phenotypic effects of genetic perturbations. However, with this technology comes the inherent risk of generating off-target effects (OTEs) in addition to the desired modifications. As such, it can be difficult to conclusively determine that the observed phenotypic changes are in fact due to the intended modification of the target gene and not from random mutations elsewhere in the genome. In addition, biological variations observed within cultured cells or laboratory animals can also confound results and need to be addressed. In this article, we review potential sources of experimental and biological variation as well as propose experimental options to minimize and control OTEs and other variations in CRISPR genome editing experiments for exploratory research applications. Confirmation of on-target KO effect by orthogonal approaches is also discussed. [ABSTRACT FROM AUTHOR]

Angiogenesis and its involved proteins, particularly Vascular Endothelial Growth Factor family (VEGFs) and VEGF receptors (VEGFRs), have been considered as a target of therapeutic interest for numerous inflammatory and vascular diseases. Acting on this biological process through interaction with VEGFs or VEGFRs has received considerable attention. Indeed, VEGFs and VEGFRs are currently targeted by drugs such as monoclonal antibodies. The feasibility of a therapeutic strategy based on blocking the VEGF/VEGFR interaction by using ligands “other-than-biologics” is also explored. To help to the discovery of new molecules, screening assays have been developed, particularly to evaluate the VEGFA/VEGFR1 interaction. Despite the therapeutic importance of VEGFB and PlGF (Placental Growth Factor), no assays have been developed to evaluate molecules against their interactions with VEGFR1. Here, we present new versatile colorimetric immunoassays to screen and evaluate the specific interaction of discovered molecules with different growth factors (VEGFA, VEGFB, PlGF) and receptors (VEGFR1, VEGFR2). These tests, based on competitive immunoassay format, will provide essential information on specificity and selectivity of molecules for their targets and will help to work on the pharmaco-modulation of molecules for targeting one specific interaction. [ABSTRACT FROM AUTHOR]

Background: Histone deacetylase (HDAC) activities modify chromatin structure and play a role in learning and memory during developmental processes. Studies of adult mice suggest HDACs are involved in neural network remodeling in brain repair, but its function in drug addiction is less understood. We aimed to examine in vivo HDAC5 expression in a preclinical model of amphetamine-induced sensitization (AIS) of behavior. We generated specific contrast agents to measure HDAC5 levels by in vivo molecular contrast-enhanced (MCE) magnetic resonance imaging (MRI) in amphetamine-naïve mice as well as in mice with AIS. To validate the MRI results we used ex vivo methods including in situ hybridization, RT-PCR, immunohistochemistry, and transmision electron microscopy. Methods: We compared the expression of HDAC5 mRNA in an acute exposure paradigm (in which animals experienced a single drug exposure [A1]) and in a chronic-abstinence-challenge paradigm (in which animals were exposed to the drug once every other day for seven doses, then underwent 2 weeks of abstinence followed by a challenge dose [A7WA]). Control groups for each of these exposure paradigms were given saline. To delineate how HDAC5 expression was related to AIS, we compared the expression of HDAC5 mRNA at sequences where no known microRNA (miR) binds (hdac5AS2) and at sequences where miR-2861 is known to bind (miD2861). We synthesized and labeled phosphorothioated oligonucleic acids (sODN) of hdac5AS2 or miD2861 linked to superparamagentic iron oxide nanoparticles (SPION), and generated HDAC5-specific contrast agents (30 ± 20 nm, diameter) for MCE MRI; the same sequences were used for primers for TaqMan® analysis (RT-qPCR) in ex vivo validation. In addition, we used subtraction R2* maps to identify regional HDAC5 expression. Results: Naïve C57black6 mice that experience acute exposure to amphetamine (4 mg/kg, by injection intraperitoneally) show expression of both total and phosphorylated (S259) HDAC5 antigens in GFAP+ and GFAP- cells, but the appearance of these cells was attenuated in the chronic paradigm. We found that MCE MRI reports HDAC5 mRNA with precision in physiological conditions because the HDAC5 mRNA copy number reported by TaqMan analysis was positively correlated (with a linear coefficient of 1.0) to the ?R2* values (the frequency of signal reduction above background, 1/s) measured by MRI. We observed SPION-mid2861 as electron dense nanoparticles (EDNs) of less than 30 nm in the nucleus of the neurons, macrophages, and microglia, but not in glia and endothelia. We found no preferential distribution in any particular type of neural cells, but observed scattered EDNs of 60-150 nm (dia) in lysosomes. In the acute paradigm, mice pretreated with miD2861 (1.2 mmol/kg, i.p./icv) exhibited AIS similar to that exibited by mice in the chronic exposure group, which exhibited null response to mid2861 pretreatment. Moreover, SPION-miD2861 identified enhanced HDAC5 expression in the lateral septum and the striatum after amphetamine, where we found neurprogenitor cells coexpressing NeuN and GFAP. Conclusions: We conclude that miD2681 targets HDAC5 mRNA with precision similar to that of RT-PCR. Our MCE MRI detects RNA-bound nanoparticles (NPs) in vivo, and ex vivo validation methods confirm that EDNs do not accumulate in any particular cell type. As HDAC5 expression may help nullify AIS and identify progenitor cells, the precise delivery of miD2861 may serve as a vehicle for monitoring network remodeling with target specificity and signal sensitivity after drug exposure that identifies brain repair processes in adult animals. [ABSTRACT FROM AUTHOR]

Gene editing allows the precise modification of cells to correct genetic defects or enhance immunotherapies. A limitation is the delivery of this technology to specific cells or organs. Recently, Banskota et al. reported the use of virus-like particles (VLPs) loaded with gene-editing agents for gene therapy delivery directly inside the body. [ABSTRACT FROM AUTHOR]

The availability of genome sequences of numerous organisms and the revolution brought about by genome editing tools (e.g., ZFNs, TALENs, and CRISPR/Cas9 or RGENs) has provided a breakthrough in introducing targeted genetic changes both to explore emergent phenotypes and to introduce new functionalities. However, the wider application of these tools in biology, agriculture, medicine, and biotechnology is limited by off-target mutation effects. In this review, we compare available methods for detecting, measuring, and analyzing off-target mutations. Furthermore, we particularly focus on CRISPR/Cas9 regarding various methods, tweaks, and software tools available to nullify off-target effects. [ABSTRACT FROM AUTHOR]

Recently, a novel technique named the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas)9 system has been rapidly developed. This genome editing tool has improved our ability tremendously with respect to exploring the pathogenesis of diseases and correcting disease mutations, as well as phenotypes. With a short guide RNA, Cas9 can be precisely directed to target sites, and functions as an endonuclease to efficiently produce breaks in DNA double strands. Over the past 30 years, CRISPR has evolved from the 'curious sequences of unknown biological function' into a promising genome editing tool. As a result of the incessant development in the CRISPR/Cas9 system, Cas9 co-expressed with custom guide RNAs has been successfully used in a variety of cells and organisms. This genome editing technology can also be applied to synthetic biology, functional genomic screening, transcriptional modulation and gene therapy. However, although CRISPR/Cas9 has a broad range of action in science, there are several aspects that affect its efficiency and specificity, including Cas9 activity, target site selection and short guide RNA design, delivery methods, off-target effects and the incidence of homology-directed repair. In the present review, we highlight the factors that affect the utilization of CRISPR/Cas9, as well as possible strategies for handling any problems. Addressing these issues will allow us to take better advantage of this technique. In addition, we also review the history and rapid development of the CRISPR/Cas system from the time of its initial discovery in 2012. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cancer making it the second most leading cause of death after cardiovascular diseases. • Though many platinum-based drugs are currently being used widely in anticancer therapy, the therapeutic value of these complexes comes with severe side effects. • Thus, a tremendous amount of research is being carried out on the anticancer activity of other metal complexes to explore their anticancer activity. • Herein, we discuss the study of cellular uptake, localisation, mechanism of action and cytotoxicity profiles of several mononuclear and multinuclear ruthenium, iridium and rhenium complexes as potential chemotherapeutic agents. More than 10 million death tolls in 2020 were reported as a result of heinous impact of cancer, making it second most prime cause of death after cardiovascular diseases. In annihilation of cancer, many platinum-based drugs are currently being applied in anticancer therapy but the therapeutic value of these complexes comes with severe side effects. Hence, a profound research is needed to develop more selective and target specific chemotherapeutics so as to diminish the side effects. In this scenario, the anticancer activity of ruthenium, iridium and rhenium-based complexes have shown a light of hope for being explored as anticancer metallotherapeutics. This present review article, therefore, delineates the study of cellular uptake, localisation, mechanism of action and cytotoxicity profiles of several mononuclear and multinuclear ruthenium, iridium and rhenium complexes as target specific potential chemotherapeutic agents. [ABSTRACT FROM AUTHOR]

The involvement of glycogen synthase kinase 3β (GSK3β) in eukaryotic cell apoptosis and the extensive potency of GSK3β inhibitors to block cell death has made it a potential drug discovery target for many grievous human disorders. GSK3β is phylogenetically related to the CDKs, such as CDK1 and CDK2, which are suggested to be the off-target proteins of GSK3β inhibitors. The present work is focused on delineating the interaction profiles crucial for the exclusion ability of GSK3β inhibitors against CDKs. With this objective in mind, we carried out molecular dynamic simulation studies on previously identified GSK3β inhibitors, docked to the kinase-binding domains of GSK3β, CDK1 and CDK2. The binding mode analysis of these ligands showed all the essential binding interactions required for the selective inhibition of GSK3β. Further, the crucial protein-ligand interactions and GSK3β-selective mechanisms of identified ligands were analyzed and discussed. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate how employees' innovative work behaviour is determined by the level of target specificity of innovation tasks, which refers to the concreteness of a task regarding the realization of an innovation. This issue was addressed in a study with 239 vocational teachers. The study investigated the assumption that employees have different task-related needs depending on whether they engage in innovation tasks with low or high target specificity. That is, with increasing target specificity, innovation-specific resources, such as perceived social support, become more important compared with general, work-related resources such as perceived impact. In addition, the study aimed to show that intrinsic motivation for innovation is a crucial requirement at all levels of target specificity. By applying structural equation and path modelling, we found that (1) the engagement in innovation tasks with low target specificity (i.e., opportunity exploration) depended on perceived impact, (2) the engagement in innovation tasks with high target specificity (i.e., idea generation, idea promotion, and reflection) was facilitated by perceived social support, and (3) intrinsic task motivation enhanced the engagement in innovation tasks at all levels of target specificity and mediated the effects of perceived impact and perceived social support. Practitioner points The development of innovations can be fostered if employees are encouraged to carry out social-interactive and reflective activities such as sharing ideas and critically analysing conditions, tasks, processes, and outcomes at work., The exploration of opportunities for innovation can be facilitated by a work environment and by job tasks, which provide experiences that increase employees' perception of influence on work processes and outcomes., Dimensions of innovative work behaviour that are related to the realization of an innovation can be facilitated by a work environment that supports innovation processes by encouraging an open dialogue about ideas, by providing appreciation and sociopolitical backing, and by guiding less experienced colleagues in the innovation process., The engagement in all innovative behaviours can be enhanced by creating an intrinsically motivating work environment that contains collaborative work structures, a safe space for errors and reflection, and sensitivity for context-specific problems and needs. [ABSTRACT FROM AUTHOR]

Circuit formation is a defining characteristic of the developing brain. However, multiple lines of evidence suggest that circuit formation can also take place in adults, the mechanisms of which remain poorly understood. Here, we investigated the epilepsy-associated mossy fiber (MF) sprouting in the adult hippocampus and asked which cell surface molecules define its target specificity. Using single-cell RNAseq data, we found lack and expression of Pcdh11x in non-sprouting and sprouting neurons respectively. Subsequently, we used CRISPR/Cas9 genome editing to disrupt the Pcdh11x gene and characterized its consequences on sprouting. Although MF sprouting still developed, its target specificity was altered. New synapses were frequently formed on granule cell somata in addition to dendrites. Our findings shed light onto a key molecular determinant of target specificity in MF sprouting and contribute to understanding the molecular mechanism of adult brain rewiring., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Luo, Cruz-Ochoa, Seng, Egger, Lukacsovich, Lukacsovich and Földy.)

Alzheimer's disease is undoubtedly the most well-studied neurodegenerative disease. Consequently, the amyloid-β (Aβ) protein ranks at the top in terms of getting attention from the scientific community for structural property-based characterization. Even after decades of extensive research, there is existing volatility in terms of understanding and hence the effective tackling procedures against the disease that arises due to the lack of knowledge of both specific target- and site-specific drugs. Here, we develop a multidimensional approach based on the characterization of the common static-dynamic-thermodynamic trait of the monomeric protein, which efficiently identifies a small target sequence that contains an inherent tendency to misfold and consequently aggregate. The robustness of the identification of the target sequence comes with an abundance of a priori knowledge about the length and sequence of the target and hence guides toward effective designing of the target-specific drug with a very low probability of bottleneck and failure. Based on the target sequence information, we further identified a specific mutant that showed the maximum potential to act as a destabilizer of the monomeric protein as well as enormous success as an aggregation suppressor. We eventually tested the drug efficacy by estimating the extent of modulation of binding affinity existing within the fibrillar form of the Aβ protein due to a single-point mutation and hence provided a proof of concept of the entire protocol.

Performance targets direct organizational participants toward firm strategy, provide guidance for allocating effort, and induce effort toward performance goals. Key aspects of the setting of performance targets are how specific they should be and at which levels they should be set. We develop a structural model that aims to explain the specificity of targets set for subordinate managers and the information sources used to set target levels for defined performance dimensions, which sources include past performance, future planning, and benchmarking information. An analysis of 364 survey responses provides support for our expectations that both target specificity and the use of information sources to determine target levels vary with firms' environmental dynamism and task uncertainty, and with the intensity of financial incentives provided to subordinate managers. In addition, the results show that in response to these contextual variables, firms typically combine information sources to determine adequate target levels, instead of treating them as substitutes. [ABSTRACT FROM AUTHOR]

Insertion sequences (ISs) are mobile genetic elements widely distributed among bacteria. Their impact on the bacterial genome is multifold, including transfer of genetic information, shuttle of adaptive traits and influence on the genomic content. As a result, ISs play an important role in the organization, plasticity and evolution of bacterial genomes. In this study, four new IS elements: IS Mbov7; IS Mbov4 and IS Mbov5; and IS Mbov6, related, respectively, to the IS 3, IS 4 and IS 30 gene families, were identified and characterized with respect to inverted repeat (IR) and directly repeated (DR) sequences, putative target specificity and motifs related to transposase function. For instance, IS 30-related IS Mbov6 isoform elements were shown to (1) contain an α-helix-turn-α-helix homeodomain (HTH), (2) generate long DR and (3) possess target specificity for a palindromic sequence derived from putative rho-independent transcription terminators. Members of the IS 3 family, which had not been documented previously in Mycoplasma bovis, contain HTH, leucine zipper and AT-hook motifs, which may be involved in DNA binding. In addition, the availability of the M. bovis PG45 genome sequence allowed us to elucidate the genomic organization of 54 intact or truncated IS elements and their possible effect on the expression of adjacent genes. [ABSTRACT FROM AUTHOR]

Activation-induced cytidine deaminase (AID) is an essential factor for the class switch recombination (CSR) and somatic hypermutation (SHM) of Ig genes. CSR and SHM are initiated by AID-induced DNA breaks in the Sand V regions, respectively. Because truncation or frame-shift mutations at the carboxyl (C)-terminus of AID abolishes CSR but not SHM. the C-terminal region of AID likely is required for the targeting of DNA breaks in the S region. To test this hypothesis, we determined the precise location and relative amounts of AID-induced DNA cleavage using an in situ DNA end-labeling method. We established CH12F3-2 cell transfectants expressing the estrogen receptor (ER) fused with wild-type (WI) AID or a deletion mutant lacking the C-terminal 16 aa, JP8Bdel. We found that AID-ER, but not JP8Bdel-ER, caused a CSR to IgA from the addition of 4-hydroxy tamoxifen. In contrast, both WI AID and JP8Bdel induced DNA breaks in both the V and S regions. In addition, JP8Bdel enhanced c-myc/IgH translocations. Our findings indicate that the C-terminal domain of AID is not required for S-region DNA breaks but is required for S-region recombination after DNA cleavage. Therefore, AID does not distinguish between the V and S regions for cleavage, but carries another function specific to CSR. [ABSTRACT FROM AUTHOR]

Abstract: Exposure of cells to sublethal oxidative stress results in the modulation of various signaling pathways. Oxidants can activate and inactivate transcription factors, membrane channels, and metabolic enzymes, and regulate calcium-dependent and phosphorylation signaling pathways. Oxidation and reduction of thiol proteins are thought to be the major mechanisms by which reactive oxidants integrate into cellular signal transduction pathways. This review focuses on mechanisms for sensing and transmitting redox signals, from the perspective of their chemical reactivity with specific oxidants. We discuss substrate preferences for different oxidants and how the kinetics of these reactions determines how each oxidant will react in a cell. This kinetic approach helps to identify initial oxidant-sensitive targets and elucidate mechanisms involved in transmission of redox signals. It indicates that only those proteins with very high reactivity, such as peroxiredoxins, are likely to be direct targets for hydrogen peroxide. Other more modestly reactive thiol proteins such as protein tyrosine phosphatases are more likely to become oxidized by an indirect mechanism. The review also examines oxidative changes observed during receptor-mediated signaling, the strengths and limitations of detection methods for reactive oxidant production, and the evidence for hydrogen peroxide acting as the second messenger. We discuss areas where observations in cell systems can be rationalized with the reactivity of specific oxidants and where further work is needed to understand the mechanisms involved. [Copyright &y& Elsevier]

OBJECTIVE: To testify that the asialoorosomucoid (ASOR) prepared by us has liver-targeting specificity and to investigate its pharmacokinetic characteristics. METHODS: The distribution of 125I-ASOR in vivo was determined by single photon emission computed tomography (SPECT) and immunohistochemical technique after 125I-ASOR was injected into Sprague-Dawley (S–D) rats through their caudal veins. In vitro, different doses of pEGFP-N1 plasmid were transfected into both HepG2 cells and HT1080 cells with the use of ASOR-poly-L-lysine. At 24 and 48 h after transfection, the expression of green fluorescent protein (GFP) was determined under fluorescent microscope. Pharmacokinetic parameters were calculated according to two-compartment open system model with first-order kinetics. RESULTS: SPECT images showed that 125I-ASOR was located only in liver/stomach and root of caudal vein / bladder at 10 min after injection. The 125I-ASOR radioactivities of organs taken out from S–D rats were different at different times, and about 63% of 125I-ASOR was located in the liver at 10 min after injection. At 30 min after injection a peak of radioactivity was seen in stomach. The times of these two radioactivity peaks were different. Immunohistochemical study of liver frozen sections showed that ASOR was combined mainly with hepatocyte membrane, especially in areas with rich blood flow. In vitro study showed that ASOR targeted specifically cells with asialoglycoprotein receptor (ASGr). GFP expression was detected in HepG2 cells but not in HT1080 cells. Furthermore, the more quantity of pEGFP-N1 transfected and the longer expression time, the higher GFP expression level was in HepG2 cells. The 125I-ASOR pharmacokinetics equation for liver was Ct = 662216e−3.362t  + 8896e−2343t. 125I-ASOR was excreted from liver slowly after an initial rapid decrease. The pharmacokinetic equation for stomach was Ct = –114815e−1.7t  + 1148153e−15t and the half-life of 125I-ASOR in stomach was 4.62 h. CONCLUSIONS: ASOR prepared by us could be an efficient gene transfer vector, ASOR was distributed mainly in the liver and stomach and had high targeting specificity to hepatocytes or hepatic originating cells. [ABSTRACT FROM AUTHOR]