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1.
Bone Res ; 12(1): 7, 2024 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-38311627

RESUMEN

Osteoarthritis (OA) is a debilitating degenerative disease affecting multiple joint tissues, including cartilage, bone, synovium, and adipose tissues. OA presents diverse clinical phenotypes and distinct molecular endotypes, including inflammatory, metabolic, mechanical, genetic, and synovial variants. Consequently, innovative technologies are needed to support the development of effective diagnostic and precision therapeutic approaches. Traditional analysis of bulk OA tissue extracts has limitations due to technical constraints, causing challenges in the differentiation between various physiological and pathological phenotypes in joint tissues. This issue has led to standardization difficulties and hindered the success of clinical trials. Gaining insights into the spatial variations of the cellular and molecular structures in OA tissues, encompassing DNA, RNA, metabolites, and proteins, as well as their chemical properties, elemental composition, and mechanical attributes, can contribute to a more comprehensive understanding of the disease subtypes. Spatially resolved biology enables biologists to investigate cells within the context of their tissue microenvironment, providing a more holistic view of cellular function. Recent advances in innovative spatial biology techniques now allow intact tissue sections to be examined using various -omics lenses, such as genomics, transcriptomics, proteomics, and metabolomics, with spatial data. This fusion of approaches provides researchers with critical insights into the molecular composition and functions of the cells and tissues at precise spatial coordinates. Furthermore, advanced imaging techniques, including high-resolution microscopy, hyperspectral imaging, and mass spectrometry imaging, enable the visualization and analysis of the spatial distribution of biomolecules, cells, and tissues. Linking these molecular imaging outputs to conventional tissue histology can facilitate a more comprehensive characterization of disease phenotypes. This review summarizes the recent advancements in the molecular imaging modalities and methodologies for in-depth spatial analysis. It explores their applications, challenges, and potential opportunities in the field of OA. Additionally, this review provides a perspective on the potential research directions for these contemporary approaches that can meet the requirements of clinical diagnoses and the establishment of therapeutic targets for OA.


Asunto(s)
Osteoartritis , Humanos , Osteoartritis/diagnóstico , Membrana Sinovial/metabolismo , Metabolómica , Fenotipo , Proteómica
2.
Mar Drugs ; 21(9)2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37755094

RESUMEN

Sea anemones are known to produce a diverse array of toxins with different cysteine-rich peptide scaffolds in their venoms. The serine peptidase inhibitors, specifically Kunitz inhibitors, are an important toxin family that is believed to function as defensive peptides, as well as prevent proteolysis of other secreted anemone toxins. In this study, we isolated three serine peptidase inhibitors named Anthopleura cascaia peptide inhibitors I, II, and III (ACPI-I, ACPI-II, and ACPI-III) from the venom of the endemic Brazilian sea anemone A. cascaia. The venom was fractionated using RP-HPLC, and the inhibitory activity of these fractions against trypsin was determined and found to range from 59% to 93%. The spatial distribution of the anemone peptides throughout A. cascaia was observed using mass spectrometry imaging. The inhibitory peptides were found to be present in the tentacles, pedal disc, and mesenterial filaments. We suggest that the three inhibitors observed during this study belong to the venom Kunitz toxin family on the basis of their similarity to PI-actitoxin-aeq3a-like and the identification of amino acid residues that correspond to a serine peptidase binding site. Our findings expand our understanding of the diversity of toxins present in sea anemone venom and shed light on their potential role in protecting other venom components from proteolysis.

3.
Theranostics ; 13(13): 4636-4649, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37649605

RESUMEN

Background: Enzymes are central components of many physiological processes, and changes in enzyme activity are linked to numerous disease states, including osteoarthritis (OA). Assessing changes in enzyme function can be challenging because of difficulties in separating affected tissue areas that result in the homogenisation of healthy and diseased cells. Direct correlation between spatially-resolved enzyme distribution(s) and diseased cells/tissues can thus lead to advances in our understanding of OA pathophysiology. Herein, we present a method that uses mass spectrometry imaging (MSI) to visualise the distribution of lipase enzymes and their downstream lipid products in fresh bone and cartilage tissue sections. Immunohistostaining of adjacent tissue sections was then used to identify OA cells/tissues, which were then statistically correlated with molecular-level images. Methods: MSI was used to image lipase enzymes, their substrates, and their metabolic products to validate enzymatic activity and correlate to OA regions determined by immunohistochemistry (IHC). Based on the modified Mankin score, six non-OA and OA patient-matched osteochondral samples were analysed by matrix-assisted laser desorption/ionisation mass spectrometry imaging (MALDI-MSI). Due to the involvement of phospholipase A2 (PLA2) in inflammatory pathways, explant tissues were treated with IL-1ß to mimic inflammation observed in OA. Bovine explant tissues were then subject to MSI methods to observe the spatial distribution of PLA2. Results: Compared with non-OA samples, OA samples showed an elevated level of multiple arachidonic acid (AA)-containing phospholipids (P < 0.001), in which the elevation in the surface and deep layer cartilage of OA tissues is correlated to elevated PLA2 activity (P < 0.001). Bovine explant tissues treated with IL-1ß to mimic OA pathophysiology validated these results and displayed elevated PLA2 levels in OA mimic samples relative to the controls (P < 0.001). It was established that the PLA2G2A isoform specifically was responsible for PLA2 enzyme activity changes in OA tissues (P < 0.001). Conclusion: Our results present a reliable method for imaging enzyme dynamics in OA cartilage, which sets up the foundation for future spatial enzyme dynamics in the OA field. We demonstrated that OA patients exhibit increased expression of PLA2G2A at the superficial and deep cartilage zone that degrades cartilage differently at the spatial level. A tissue-specific PLA2G2A precision inhibition may be the potential target for OA.


Asunto(s)
Osteoartritis , Humanos , Animales , Bovinos , Osteoartritis/diagnóstico por imagen , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Inflamación , Lipasa , Poliésteres
4.
BMC Biol ; 21(1): 121, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-37226201

RESUMEN

BACKGROUND: The ShK toxin from Stichodactyla helianthus has established the therapeutic potential of sea anemone venom peptides, but many lineage-specific toxin families in Actiniarians remain uncharacterised. One such peptide family, sea anemone 8 (SA8), is present in all five sea anemone superfamilies. We explored the genomic arrangement and evolution of the SA8 gene family in Actinia tenebrosa and Telmatactis stephensoni, characterised the expression patterns of SA8 sequences, and examined the structure and function of SA8 from the venom of T. stephensoni. RESULTS: We identified ten SA8-family genes in two clusters and six SA8-family genes in five clusters for T. stephensoni and A. tenebrosa, respectively. Nine SA8 T. stephensoni genes were found in a single cluster, and an SA8 peptide encoded by an inverted SA8 gene from this cluster was recruited to venom. We show that SA8 genes in both species are expressed in a tissue-specific manner and the inverted SA8 gene has a unique tissue distribution. While the functional activity of the SA8 putative toxin encoded by the inverted gene was inconclusive, its tissue localisation is similar to toxins used for predator deterrence. We demonstrate that, although mature SA8 putative toxins have similar cysteine spacing to ShK, SA8 peptides are distinct from ShK peptides based on structure and disulfide connectivity. CONCLUSIONS: Our results provide the first demonstration that SA8 is a unique gene family in Actiniarians, evolving through a variety of structural changes including tandem and proximal gene duplication and an inversion event that together allowed SA8 to be recruited into the venom of T. stephensoni.


Asunto(s)
Anémonas de Mar , Animales , Anémonas de Mar/genética , Genómica , Inversión Cromosómica , Cisteína , Disulfuros
5.
Commun Chem ; 6(1): 48, 2023 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-36871076

RESUMEN

Macrocyclisation of proteins and peptides results in a remarkable increase in structural stability, making cyclic peptides and proteins of great interest in drug discovery-either directly as drug leads or as in the case of cyclised nanodiscs (cNDs), as tools for studies of trans-membrane receptors and membrane-active peptides. Various biological methods have been developed that are capable of yielding head-to-tail macrocyclised products. Recent advances in enzyme-catalysed macrocyclisation include discovery of new enzymes or design of new engineered enzymes. Here, we describe the engineering of a self-cyclising "autocyclase" protein, capable of performing a controllable unimolecular reaction for generation of cyclic biomolecules in high yield. We characterise the self-cyclisation reaction mechanism, and demonstrate how the unimolecular reaction path provides alternative avenues for addressing existing challenges in enzymatic cyclisation. We use the method to produce several notable cyclic peptides and proteins, demonstrating how autocyclases offer a simple, alternative way to access a vast diversity of macrocyclic biomolecules.

6.
J Med Chem ; 66(1): 538-552, 2023 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-36516997

RESUMEN

Multimodal imaging provides rich biological information, which can be exploited to study drug activity, disease associated phenotypes, and pharmacological responses. Here we show discovery and validation of a new probe targeting the endocannabinoid α/ß-hydrolase domain 6 (ABHD6) enzyme by utilizing positron emission tomography (PET) and matrix-assisted laser desorption/ionization (MALDI) imaging. [18F]JZP-MA-11 as the first PET ligand for in vivo imaging of the ABHD6 is reported and specific uptake in ABHD6-rich peripheral tissues and major brain regions was demonstrated using PET. A proof-of-concept study in nonhuman primate confirmed brain uptake. In vivo pharmacological response upon ABHD6 inhibition was observed by MALDI imaging. These synergistic imaging efforts used to identify biological information cannot be obtained by a single imaging modality and hold promise for improving the understanding of ABHD6-mediated endocannabinoid metabolism in peripheral and central nervous system disorders.


Asunto(s)
Endocannabinoides , Hidrolasas , Animales , Endocannabinoides/metabolismo , Hidrolasas/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Monoacilglicerol Lipasas , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Tomografía de Emisión de Positrones
7.
J Biol Chem ; 298(8): 102218, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35780839

RESUMEN

The stinging hairs of plants from the family Urticaceae inject compounds that inflict pain to deter herbivores. The sting of the New Zealand tree nettle (Urtica ferox) is among the most painful of these and can cause systemic symptoms that can even be life-threatening; however, the molecular species effecting this response have not been elucidated. Here we reveal that two classes of peptide toxin are responsible for the symptoms of U. ferox stings: Δ-Uf1a is a cytotoxic thionin that causes pain via disruption of cell membranes, while ß/δ-Uf2a defines a new class of neurotoxin that causes pain and systemic symptoms via modulation of voltage-gated sodium (NaV) channels. We demonstrate using whole-cell patch-clamp electrophysiology experiments that ß/δ-Uf2a is a potent modulator of human NaV1.5 (EC50: 55 nM), NaV1.6 (EC50: 0.86 nM), and NaV1.7 (EC50: 208 nM), where it shifts the activation threshold to more negative potentials and slows fast inactivation. We further found that both toxin classes are widespread among members of the Urticeae tribe within Urticaceae, suggesting that they are likely to be pain-causing agents underlying the stings of other Urtica species. Comparative analysis of nettles of Urtica, and the recently described pain-causing peptides from nettles of another genus, Dendrocnide, indicates that members of tribe Urticeae have developed a diverse arsenal of pain-causing peptides.


Asunto(s)
Neurotoxinas , Péptidos , Toxinas Biológicas , Urticaceae , Humanos , Neurotoxinas/química , Dolor , Técnicas de Placa-Clamp , Péptidos/química , Péptidos/toxicidad , Toxinas Biológicas/química , Urticaceae/química , Canales de Sodio Activados por Voltaje/efectos de los fármacos
8.
BMC Biol ; 20(1): 148, 2022 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-35761243

RESUMEN

BACKGROUND: Venoms are ecological innovations that have evolved numerous times, on each occasion accompanied by the co-evolution of specialised morphological and behavioural characters for venom production and delivery. The close evolutionary interdependence between these characters is exemplified by animals that control the composition of their secreted venom. This ability depends in part on the production of different toxins in different locations of the venom gland, which was recently documented in venomous snakes. Here, we test the hypothesis that the distinct spatial distributions of toxins in snake venom glands are an adaptation that enables the secretion of venoms with distinct ecological functions. RESULTS: We show that the main defensive and predatory peptide toxins are produced in distinct regions of the venom glands of the black-necked spitting cobra (Naja nigricollis), but these distributions likely reflect developmental effects. Indeed, we detected no significant differences in venom collected via defensive 'spitting' or predatory 'biting' events from the same specimens representing multiple lineages of spitting cobra. We also found the same spatial distribution of toxins in a non-spitting cobra and show that heterogeneous toxin distribution is a feature shared with a viper with primarily predatory venom. CONCLUSIONS: Our findings suggest that heterogeneous distributions of toxins are not an adaptation to controlling venom composition in snakes. Instead, it likely reflects physiological constraints on toxin production by the venom glands, opening avenues for future research on the mechanisms of functional differentiation of populations of protein-secreting cells within adaptive contexts.


Asunto(s)
Venenos de Serpiente , Serpientes , Animales , Venenos de Serpiente/química
9.
Mol Biol Evol ; 39(5)2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35512366

RESUMEN

Ribbon worms are active predators that use an eversible proboscis to inject venom into their prey and defend themselves with toxic epidermal secretions. Previous work on nemertean venom has largely focused on just a few species and has not investigated the different predatory and defensive secretions in detail. Consequently, our understanding of the composition and evolution of ribbon worm venoms is still very limited. Here, we present a comparative study of nemertean venom combining RNA-seq differential gene expression analyses of venom-producing tissues, tandem mass spectrometry-based proteomics of toxic secretions, and mass spectrometry imaging of proboscis sections, to shed light onto the composition and evolution of predatory and defensive toxic secretions in Antarctonemertes valida. Our analyses reveal a wide diversity of putative defensive and predatory toxins with tissue-specific gene expression patterns and restricted distributions to the mucus and proboscis proteomes respectively, suggesting that ribbon worms produce distinct toxin cocktails for predation and defense. Our results also highlight the presence of numerous lineage-specific toxins, indicating that venom evolution is highly divergent across nemerteans, producing toxin cocktails that might be finely tuned to subdue different prey. Our data also suggest that the hoplonemertean proboscis is a highly specialized predatory organ that seems to be involved in a variety of biological functions besides predation, including secretion and sensory perception. Overall, our results advance our knowledge into the diversity and evolution of nemertean venoms and highlight the importance of combining different types of data to characterize toxin composition in understudied venomous organisms.


Asunto(s)
Conducta Predatoria , Proteoma , Animales , Proteómica , Ponzoñas/genética
10.
FASEB J ; 36(2): e22142, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35032407

RESUMEN

The calcified cartilage zone (CCZ) is a thin interlayer between the hyaline articular cartilage and the subchondral bone and plays an important role in maintaining the joint homeostasis by providing biological and mechanical support from unmineralized cartilage to the underlying mineralized subchondral bone. The hallmark of CCZ characteristics in osteoarthritis (OA) is less well known. The aim of our study is to evaluate the structural, molecular, and biochemical composition of CCZ in tissues affected by primary knee OA and its relationship with disease severity. We collected osteochondral tissue samples stratified according to disease severity, from 16 knee OA patients who underwent knee replacement surgery. We also used meniscectomy-induced rat samples to confirm the pathophysiologic changes of human samples. We defined the characteristics of the calcified cartilage layer using a combination of morphological, biochemical, proteomic analyses on laser micro-dissected tissue. Our results demonstrated that the Calcium/Phosphate ratio is unchanged during the OA progression, but the calcium-binding protein and cadherin binding protein, as well as carbohydrate metabolism-related proteins, undergo significant changes. These changes were further accompanied by thinning of the CCZ, loss of collagen and proteoglycan content, the occurrence of the endochondral ossification, neovasculature, loss of the elastic module, loss of the collagen direction, and increase of the tortuosity indicating an altered structural and mechanical properties of the CCZ in OA. In conclusion, our results suggest that the calcified cartilage changes can reflect the disease progression.


Asunto(s)
Cartílago Articular/metabolismo , Osteoartritis/metabolismo , Animales , Huesos/metabolismo , Calcificación Fisiológica/fisiología , Progresión de la Enfermedad , Femenino , Humanos , Articulación de la Rodilla/metabolismo , Osteogénesis/fisiología , Proteoglicanos/metabolismo , Proteómica/métodos , Ratas
11.
J Am Soc Mass Spectrom ; 33(3): 592-597, 2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35084175

RESUMEN

In this paper, we investigate the presence of latrunculin A in the outer rim of a nudibranch Chromodoris kuiteri and show that by combining ultrathin cryosection methods with MALDI MSI we can achieve improved lateral (x and y) resolution and very high resolution in the z dimension by virtue of the ultrathin 200 nm thin cryosections. We also demonstrate that a post ionization laser increases sensitivity. Recent advances in MALDI source design have improved the lateral resolution (x and y) and sensitivity during MSI. Taken together, very high z resolution, from ultrathin sections, and improved lateral (x and y) resolution will allow for subcellular molecular imaging with the potential for subcellular 3D volume reconstruction.


Asunto(s)
Crioultramicrotomía/métodos , Imagen Molecular/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes/análisis , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Gastrópodos/química , Procesamiento de Imagen Asistido por Computador , Tiazolidinas/análisis , Tiazolidinas/química
12.
Mol Ecol ; 31(3): 866-883, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34837433

RESUMEN

The phylum Cnidaria is the oldest extant venomous group and is defined by the presence of nematocysts, specialized organelles responsible for venom production and delivery. Although toxin peptides and the cells housing nematocysts are distributed across the entire animal, nematocyte and venom profiles have been shown to differ across morphological structures in actiniarians. In this study, we explore the relationship between patterns of toxin expression and the ecological roles of discrete anatomical structures in Telmatactis stephensoni. Specifically, using a combination of proteomic and transcriptomic approaches, we examined whether there is a direct correlation between the functional similarity of regions and the similarity of their associated toxin expression profiles. We report that the regionalization of toxin production is consistent with the partitioning of the ecological roles of venom across envenomating structures, and that three major functional regions are present in T. stephensoni: tentacles, epidermis and gastrodermis. Additionally, we find that most structures that serve similar functions not only have comparable putative toxin profiles but also similar nematocyst types. There was no overlap in the putative toxins identified using proteomics and transcriptomics, but the expression patterns of specific milked venom peptides were conserved across RNA-sequencing and mass spectrometry imaging data sets. Furthermore, based on our data, it appears that acontia of T. stephensoni may be transcriptionally inactive and only mature nematocysts are present in the distal portions of the threads. Overall, we find that the venom profile of different anatomical regions in sea anemones varies according to its ecological functions.


Asunto(s)
Venenos de Cnidarios , Anémonas de Mar , Animales , Proteómica , Anémonas de Mar/genética , Análisis de Secuencia de ARN , Transcriptoma
13.
Sci Rep ; 11(1): 13282, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-34168165

RESUMEN

The venom duct origins of predatory and defensive venoms has not been studied for hook-and-line fish hunting cone snails despite the pharmacological importance of their venoms. To better understand the biochemistry and evolution of injected predatory and defensive venoms, we compared distal, central and proximal venom duct sections across three specimens of C. striatus (Pionoconus) using proteomic and transcriptomic approaches. A total of 370 conotoxin precursors were identified from the whole venom duct transcriptome. Milked defensive venom was enriched with a potent cocktail of proximally expressed inhibitory α-, ω- and µ-conotoxins compared to milked predatory venom. In contrast, excitatory κA-conotoxins dominated both the predatory and defensive venoms despite their distal expression, suggesting this class of conotoxin can be selectively expressed from the same duct segment in response to either a predatory or defensive stimuli. Given the high abundance of κA-conotoxins in the Pionoconus clade, we hypothesise that the κA-conotoxins have evolved through adaptive evolution following their repurposing from ancestral inhibitory A superfamily conotoxins to facilitate the dietary shift to fish hunting and species radiation in this clade.


Asunto(s)
Conotoxinas/metabolismo , Caracol Conus/metabolismo , Animales , Evolución Biológica , Conotoxinas/genética , Caracol Conus/anatomía & histología , Caracol Conus/fisiología , Perfilación de la Expresión Génica , Conducta Predatoria , Proteómica , Alineación de Secuencia , Transcriptoma/genética
14.
Sci Adv ; 6(38)2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32938666

RESUMEN

Stinging trees from Australasia produce remarkably persistent and painful stings upon contact of their stiff epidermal hairs, called trichomes, with mammalian skin. Dendrocnide-induced acute pain typically lasts for several hours, and intermittent painful flares can persist for days and weeks. Pharmacological activity has been attributed to small-molecule neurotransmitters and inflammatory mediators, but these compounds alone cannot explain the observed sensory effects. We show here that the venoms of Australian Dendrocnide species contain heretofore unknown pain-inducing peptides that potently activate mouse sensory neurons and delay inactivation of voltage-gated sodium channels. These neurotoxins localize specifically to the stinging hairs and are miniproteins of 4 kDa, whose 3D structure is stabilized in an inhibitory cystine knot motif, a characteristic shared with neurotoxins found in spider and cone snail venoms. Our results provide an intriguing example of inter-kingdom convergent evolution of animal and plant venoms with shared modes of delivery, molecular structure, and pharmacology.

15.
Proteomics ; 20(17-18): e1900324, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32820606

RESUMEN

Animal venoms are renowned for their toxicity, biochemical complexity, and as a source of compounds with potential applications in medicine, agriculture, and industry. Polypeptides underlie much of the pharmacology of animal venoms, and elucidating these arsenals of polypeptide toxins-known as the venom proteome or venome-is an important step in venom research. Proteomics is used for the identification of venom toxins, determination of their primary structure including post-translational modifications, as well as investigations into the physiology underlying their production and delivery. Advances in proteomics and adjacent technologies has led to a recent upsurge in publications reporting venom proteomes. Improved mass spectrometers, better proteomic workflows, and the integration of next-generation sequencing of venom-gland transcriptomes and venomous animal genomes allow quicker and more accurate profiling of venom proteomes with greatly reduced starting material. Technologies such as imaging mass spectrometry are revealing additional insights into the mechanism, location, and kinetics of venom toxin production. However, these numerous new developments may be overwhelming for researchers designing venom proteome studies. Here, the field of venom proteomics is reviewed and some practical solutions for simplifying mass spectrometry workflows to study animal venoms are offered.


Asunto(s)
Proteoma , Proteómica , Animales , Espectrometría de Masas , Proteoma/genética , Transcriptoma , Ponzoñas
16.
Angew Chem Int Ed Engl ; 59(10): 3855-3858, 2020 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-31854493

RESUMEN

Enzymes are central components of most physiological processes, and are consequently implicated in various pathologies. High-resolution maps of enzyme activity within tissues therefore represent powerful tools for elucidating enzymatic functions in health and disease. Here, we present a novel mass spectrometry imaging (MSI) method for assaying the spatial distribution of enzymatic activity directly from tissue. MSI analysis of tissue sections exposed to phospholipid substrates produced high-resolution maps of phospholipase activity and specificity, which could subsequently be compared to histological images of the same section. Functional MSI thus represents a new and generalisable method for imaging biological activity in situ.


Asunto(s)
Imagen Molecular , Fosfolipasas A2/metabolismo , Animales , Espectrometría de Masas , Naja naja , Fosfolipasas A2/química , Venenos de Serpiente/enzimología , Especificidad de la Especie
17.
Mar Drugs ; 17(12)2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31842369

RESUMEN

Serine proteases play pivotal roles in normal physiology and a spectrum of patho-physiological processes. Accordingly, there is considerable interest in the discovery and design of potent serine protease inhibitors for therapeutic applications. This led to concerted efforts to discover versatile and robust molecular scaffolds for inhibitor design. This investigation is a bioprospecting study that aims to isolate and identify protease inhibitors from the cnidarian Actinia tenebrosa. The study isolated two Kunitz-type protease inhibitors with very similar sequences but quite divergent inhibitory potencies when assayed against bovine trypsin, chymostrypsin, and a selection of human sequence-related peptidases. Homology modeling and molecular dynamics simulations of these inhibitors in complex with their targets were carried out and, collectively, these methodologies enabled the definition of a versatile scaffold for inhibitor design. Thermal denaturation studies showed that the inhibitors were remarkably robust. To gain a fine-grained map of the residues responsible for this stability, we conducted in silico alanine scanning and quantified individual residue contributions to the inhibitor's stability. Sequences of these inhibitors were then used to search for Kunitz homologs in an A. tenebrosa transcriptome library, resulting in the discovery of a further 14 related sequences. Consensus analysis of these variants identified a rich molecular diversity of Kunitz domains and expanded the palette of potential residue substitutions for rational inhibitor design using this domain.


Asunto(s)
Cnidarios/clasificación , Serina Proteasas/efectos de los fármacos , Inhibidores de Serina Proteinasa/farmacología , Animales , Bovinos , Quimotripsina/antagonistas & inhibidores , Quimotripsina/metabolismo , Simulación por Computador , Humanos , Simulación de Dinámica Molecular , Serina Proteasas/metabolismo , Inhibidores de Serina Proteinasa/aislamiento & purificación , Tripsina/efectos de los fármacos , Tripsina/metabolismo , Inhibidores de Tripsina/aislamiento & purificación , Inhibidores de Tripsina/farmacología
18.
Can J Hosp Pharm ; 72(5): 353-359, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31692538

RESUMEN

BACKGROUND: Canadian pharmacy practice residency programs promote development of key competencies for direct patient care resulting in resolution of drug therapy problems (DTPs), which is 1 of 8 national clinical pharmacy key performance indicators. There are no Canadian data on the contribution of residents to resolution of DTPs, including DTPs for priority diseases covered in disease-state education modules (PD-DTPs) or quality indicator DTPs (QI-DPTs), as assessed through application of evidence-based interventions proven to reduce morbidity, mortality, or health resource utilization. OBJECTIVE: To describe the contribution of pharmacy practice residents to direct patient care using 3 process-of-care measures: resident-resolved DTPs, PD-DTPs, and QI-DTPs. METHODS: This prospective, observational single-group study was conducted across 5 rotation sites within the authors' health authority from September 2, 2013, to June 13, 2014. The primary outcome was number of DTPs resolved. The secondary outcomes were number of PD-DTPs resolved; number of QI-DTPs resolved; numbers of DTPs, PD-DTPs, and QI-DTPs resolved over time; and residents' satisfaction with electronic tracking of resolved DTPs (in terms of training, usability, efficiency, and time requirements). RESULTS: Four residents completed a total of twenty-one 4-week rotations and resolved a total of 1201 DTPs. Of these, 620 (52%) were PD-DTPs and 479 (40%) were QI-DTPs. Overall, the number of interventions increased for rotations 1-3, decreased for rotations 4 and 5, and increased again for rotation 6. The median score for all questions in all domains of the satisfaction survey was 4 out of 5 ("agree"). CONCLUSIONS: Pharmacy practice residents were resolving DTPs, PD-DTPs, and QI-DTPs for patients and were contributing significantly to direct patient care. On the basis of literature evidence, the number and type of interventions observed in this study would be expected to improve clinical and health economic outcomes for patients.


CONTEXTE: Les programmes de résidence canadiens en pratique pharmaceutique encouragent le développement de compétences clés relatives aux soins directs offerts aux patients. Ces compétences entraîneront la résolution des problèmes de pharmacothérapie (DTP), l'un des huit indicateurs clés nationaux de rendement relatifs à la pharmacie clinique. Il n'existe pas de données canadiennes portant sur la contribution des résidents à la résolution des problèmes de pharmacothérapie, notamment ceux relatifs aux maladies prioritaires (PD-DTP) couverts dans les modules d'éducation sur les problèmes de santé, ou les indicateurs de qualité des DTP (QI-DPT), évalués au moyen d'interventions fondées sur des données scientifiques dont il a été prouvé qu'elles réduisaient la morbidité, la mortalité ou l'utilisation des ressources sanitaires. Dans une étude, les intervenants avaient des opinions divergentes concernant la contribution des résidents à la résolution des DTP, des PD-DTP et des QI-DTP. OBJECTIF: Décrire la contribution des résidents dans le cadre de la pratique pharmaceutique des soins directs offerts aux patients à l'aide de trois mesures spécifiques du processus des soins : DTP, PD-DTP et QI-DTP résolus par les résidents. MÉTHODES: Cette étude prospective par observation portant sur un seul groupe a été menée dans cinq sites de rotation compris dans la sphère d'autorité sanitaire des auteurs, du 2 septembre 2013 au 13 juin 2014. Le résultat principal était le nombre de DTP résolus. Les résultats secondaires étaient les suivants : nombre de PD-DTP résolus; nombre de QI-DTP résolus; nombre de DTP, de PD-DTP et de QI-DTP résolus avec le temps; et la satisfaction des résidents à l'égard du suivi électronique de leurs DTP résolus (en termes de formation, de facilité d'utilisation, d'efficacité et d'exigences en matière de temps). RÉSULTATS: Quatre résidents ont effectué un total de 21 rotations de quatre semaines et ont résolu 1201 DTP. De ceux-ci, 620 (52 %) étaient des PD-DTP et 479 (40 %), des QI-DTP. Les interventions générales ont augmenté de la 1re à la 3e rotation; elles ont diminué à la 4e et à la 5e rotation; elles ont à nouveau augmenté à la 6e rotation. Le score moyen de toutes les questions posées dans l'enquête de satisfaction, tous domaines confondus, était de 4 sur 5 (ou « d'accord ¼). CONCLUSIONS: Les résidents en pratique pharmaceutique résolvaient les DTP, les PD-DTP et les QI-DTP des patients et contribuaient de manière significative aux soins directs aux patients. Sur base de la documentation, on pourrait s'attendre à ce que le nombre et le type d'interventions observées dans cette étude améliorent les résultats cliniques et sanitaires des patients.

19.
Mol Ecol ; 28(9): 2272-2289, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30913335

RESUMEN

Members of phylum Cnidaria are an ancient group of venomous animals and rely on a number of specialized tissues to produce toxins in order to fulfil a range of ecological roles including prey capture, defence against predators, digestion and aggressive encounters. However, limited comprehensive analyses of the evolution and expression of toxin genes currently exist for cnidarian species. In this study, we use genomic and transcriptomic sequencing data to examine gene copy number variation and selective pressure on toxin gene families in phylum Cnidaria. Additionally, we use quantitative RNA-seq and mass spectrometry imaging to understand expression patterns and tissue localization of toxin production in sea anemones. Using genomic data, we demonstrate that the first large-scale expansion and diversification of known toxin genes occurs in phylum Cnidaria, a process we also observe in other venomous lineages, which we refer to as convergent amplification. Our analyses of selective pressure on sea anemone toxin gene families reveal that purifying selection is the dominant mode of evolution for these genes and that phylogenetic inertia is an important determinant of toxin gene complement in this group. The gene expression and tissue localization data revealed that specific genes and proteins from toxin gene families show strong patterns of tissue and developmental-phase specificity in sea anemones. Overall, convergent amplification and phylogenetic inertia have strongly influenced the distribution and evolution of the toxin complement observed in sea anemones, while the production of venoms with different compositions across tissues is related to the functional and ecological roles undertaken by each tissue type.


Asunto(s)
Venenos de Cnidarios/genética , Expresión Génica , Anémonas de Mar/genética , Animales , Venenos de Cnidarios/química , Espectrometría de Masas , Filogenia , Selección Genética , Análisis de Secuencia de ARN
20.
Intern Med J ; 49(8): 1010-1015, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30693623

RESUMEN

BACKGROUND: The introduction of the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death protein 1 (PD-1) immune checkpoint inhibitors and their subsequent listing on the Pharmaceutical Benefits Scheme for use in metastatic melanomas, renal cell carcinomas and non-small-cell lung cancers has resulted in routine use of these agents in oncology practices, including in regional areas. Although immunotherapeutic agents generally have a favourable toxicity profile compared to chemotherapy, they can provoke immune-related adverse effects (irAE) caused by an unregulated and hyperstimulated immune response. Some of these effects can be serious and life-threatening. AIMS: To compare the utilisation of immunotherapy and the rates, management and outcomes of irAE between a regional oncology service and a tertiary service. METHODS: We reviewed the medical records for all patients treated with immunotherapy in the participating services for the 5-year period from 31 July 2012 to 31 July 2017. RESULTS: Data demonstrated that rates of immunotherapy use are both similar and increasing across the tertiary and regional services. The rates, types and severity of irAE are equivalent and in concordance with pre-existing literature. Immune-related adverse events appear to be identified and treated earlier in the regional service with the corresponding reduction in the duration of immunosuppression and requirement for inpatient management. CONCLUSION: The use of immunotherapy in a regional setting is safe and equivalent to that of a tertiary centre.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Inmunoterapia/métodos , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , Antígeno CTLA-4/antagonistas & inhibidores , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Femenino , Humanos , Inmunoterapia/efectos adversos , Masculino , Melanoma/secundario , Persona de Mediana Edad , Estadificación de Neoplasias , Servicio de Oncología en Hospital , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Estudios Retrospectivos , Neoplasias Cutáneas/secundario , Centros de Atención Terciaria , Melanoma Cutáneo Maligno
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