scholarly journals Quantification of vascular networks in photoacoustic mesoscopy

2021 ◽  
Author(s):  
Emma L Brown ◽  
Thierry L Lefebvre ◽  
Paul W Sweeney ◽  
Bernadette Stolz ◽  
Janek Gröhl ◽  
...  
Keyword(s):  
Blood Volume ◽  
Network Structure ◽  
In Silico ◽  
Ex Vivo ◽  
Image Filtering ◽  
Vascular Networks ◽  
Ground Truth Data ◽  
Rule Based ◽  
Segmentation Methods

Mesoscopic photoacoustic imaging (PAI) enables non-invasive visualisation of tumour vasculature and has the potential to assess prognosis and therapeutic response. Currently, evaluating vasculature using mesoscopic PAI involves visual or semi-quantitative 2D measurements, which fail to capture 3D vessel network complexity, and lack robust ground truths for assessment of segmentation accuracy. Here, we developed an in silico, phantom, in vivo, and ex vivo-validated end-to-end framework to quantify 3D vascular networks captured using mesoscopic PAI. We applied our framework to evaluate the capacity of rule-based and machine learning-based segmentation methods, with or without vesselness image filtering, to preserve blood volume and network structure by employing topological data analysis. We first assessed segmentation performance against ground truth data of in silico synthetic vasculatures and a photoacoustic string phantom. Our results indicate that learning-based segmentation best preserves vessel diameter and blood volume at depth, while rule-based segmentation with vesselness image filtering accurately preserved network structure in superficial vessels. Next, we applied our framework to breast cancer patient-derived xenografts (PDXs), with corresponding ex vivo immunohistochemistry. We demonstrated that the above segmentation methods can reliably delineate the vasculature of 2 breast PDX models from mesoscopic PA images. Our results underscore the importance of evaluating the choice of segmentation method when applying mesoscopic PAI as a tool to evaluate vascular networks in vivo.

scholarly journals In Silico Predicted Antifungal Peptides: In Vitro and In Vivo Anti-Candida Activity

2021 ◽  
Vol 7 (6) ◽  
pp. 439
Author(s):  
Tecla Ciociola ◽  
Walter Magliani ◽  
Tiziano De Simone ◽  
Thelma A. Pertinhez ◽  
Stefania Conti ◽  
...  
Keyword(s):  
In Silico ◽  
Mammalian Cells ◽  
Galleria Mellonella ◽  
Ex Vivo ◽  
Consensus Sequence ◽  
In Silico Analysis ◽  
Significant Activity ◽  
Synthetic Antibody

It has been previously demonstrated that synthetic antibody-derived peptides could exert a significant activity in vitro, ex vivo, and/or in vivo against microorganisms and viruses, as well as immunomodulatory effects through the activation of immune cells. Based on the sequence of previously described antibody-derived peptides with recognized antifungal activity, an in silico analysis was conducted to identify novel antifungal candidates. The present study analyzed the candidacidal and structural properties of in silico designed peptides (ISDPs) derived by amino acid substitutions of the parent peptide KKVTMTCSAS. ISDPs proved to be more active in vitro than the parent peptide and all proved to be therapeutic in Galleria mellonella candidal infection, without showing toxic effects on mammalian cells. ISDPs were studied by circular dichroism spectroscopy, demonstrating different structural organization. These results allowed to validate a consensus sequence for the parent peptide KKVTMTCSAS that may be useful in the development of novel antimicrobial molecules.

Synthesis and characterization of Chitosan-Catechol conjugates: Development and in vitro, in silico and in vivo evaluation of mucoadhesive pellets of lafutidine

2021 ◽  
pp. 088391152199784
Author(s):  
Loveleen Kaur ◽  
Ajay Kumar Thakur ◽  
Pradeep Kumar ◽  
Inderbir Singh
Keyword(s):  
Drug Release ◽  
In Silico ◽  
Ex Vivo ◽  
Strong Interactions ◽  
Dissolution Time ◽  
Sem Images ◽  
In Vivo Evaluation ◽  
Release Studies

Present study was aimed to synthesize and characterize Chitosan-Catechol conjugates and to design and develop mucoadhesive pellets loaded with lafutidine. SEM images indicated the presence of fibrous structures responsible for enhanced mucoadhesive potential of Chitosan-Catechol conjugates. Thermodynamic stability and amorphous nature of conjugates was confirmed by DSC and XRD studies respectively. Rheological studies were used to evaluate polymer mucin interactions wherein strong interactions between Chitosan-Catechol conjugate and mucin was observed in comparison to pristine chitosan and mucin. The mucoadhesion potential of Chitosan-Catechol (Cht-C) versus Chitosan (Cht) was assessed in silico using molecular mechanics simulations and the results obtained were compared with the in vitro and ex vivo results. Cht-C/mucin demonstrated much higher energy stabilization (∆E ≈ −65 kcal/mol) as compared to Cht/mucin molecular complex. Lafutidine-loaded pellets were prepared from Chitosan (LPC) and Chitosan-Catechol conjugates (LPCC) and were evaluated for various physical properties viz. flow, circularity, roundness, friability, drug content, particle size and percent mucoadhesion. In vitro drug release studies on LPC and LPCC pellets were performed for computing t50%, t90% and mean dissolution time. The values of release exponent from Korsmeyer-Peppas model was reported to be 0.443 and 0.759 for LPC and LPCC pellets suggesting Fickian and non-Fickian mechanism representing drug release, respectively. In vivo results depicted significant controlled release and enhanced residence of the drug after being released from the chitosan-catechol coated pellets. Chitosan-Catechol conjugates were found to be a promising biooadhesive polymer for the development of various mucoadhesive formulations.

A Dual-Biotic System for the Concurrent Delivery of Antibiotics and Probiotics: In Vitro, Ex Vivo, In Vivo and In Silico Evaluation and Correlation

2016 ◽  
Vol 33 (12) ◽  
pp. 3057-3071 ◽  
Author(s):  
Mershen Govender ◽  
Yahya E. Choonara ◽  
Sandy van Vuuren ◽  
Pradeep Kumar ◽  
Lisa C. du Toit ◽  
...  
Keyword(s):  
In Silico ◽  
Ex Vivo

scholarly journals How Can Biomolecules Improve Mucoadhesion of Oral Insulin? A Comprehensive Insight using Ex-Vivo, In Silico, and In Vivo Models

Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 675 ◽  
Author(s):  
Mariana Amaral ◽  
Ana Sofia Martins ◽  
José Catarino ◽  
Pedro Faísca ◽  
Pradeep Kumar ◽  
...  
Keyword(s):  
In Silico ◽  
Ex Vivo ◽  
Polymeric Nanoparticles ◽  
Spherical Shape ◽  
Diabetic Rats ◽  
Laser Scattering ◽  
In Vivo Models ◽  
Mean Size

Currently, insulin can only be administered through the subcutaneous route. Due to the flaws associated with this route, it is of interest to orally deliver this drug. However, insulin delivered orally has several barriers to overcome as it is degraded by the stomach’s low pH, enzymatic content, and poor absorption in the gastrointestinal tract. Polymers with marine source like chitosan are commonly used in nanotechnology and drug delivery due to their biocompatibility and special features. This work focuses on the preparation and characterization of mucoadhesive insulin-loaded polymeric nanoparticles. Results showed a suitable mean size for oral administration (<600 nm by dynamic laser scattering), spherical shape, encapsulation efficiency (59.8%), and high recovery yield (80.6%). Circular dichroism spectroscopy demonstrated that protein retained its secondary structure after encapsulation. Moreover, the mucoadhesive potential of the nanoparticles was assessed in silico and the results, corroborated with ex-vivo experiments, showed that using chitosan strongly increases mucoadhesion. Besides, in vitro and in vivo safety assessment of the final formulation were performed, showing no toxicity. Lastly, the insulin-loaded nanoparticles were effective in reducing diabetic rats’ glycemia. Overall, the coating of insulin-loaded nanoparticles with chitosan represents a potentially safe and promising approach to protect insulin and enhance peroral delivery.

scholarly journals ADAM22/LGI1 complex as a new actionable target for breast cancer brain metastasis

BMC Medicine ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Sara Charmsaz ◽  
Ben Doherty ◽  
Sinéad Cocchiglia ◽  
Damir Varešlija ◽  
Attilio Marino ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Metastatic Breast Cancer ◽  
Brain Metastasis ◽  
In Silico ◽  
Ex Vivo ◽  
Metastatic Breast ◽  
Peptide Mimetic ◽  
Breast Cancer Brain Metastasis

Abstract Background Metastatic breast cancer is a major cause of cancer-related deaths in woman. Brain metastasis is a common and devastating site of relapse for several breast cancer molecular subtypes, including oestrogen receptor-positive disease, with life expectancy of less than a year. While efforts have been devoted to developing therapeutics for extra-cranial metastasis, drug penetration of blood–brain barrier (BBB) remains a major clinical challenge. Defining molecular alterations in breast cancer brain metastasis enables the identification of novel actionable targets. Methods Global transcriptomic analysis of matched primary and metastatic patient tumours (n = 35 patients, 70 tumour samples) identified a putative new actionable target for advanced breast cancer which was further validated in vivo and in breast cancer patient tumour tissue (n = 843 patients). A peptide mimetic of the target’s natural ligand was designed in silico and its efficacy assessed in in vitro, ex vivo and in vivo models of breast cancer metastasis. Results Bioinformatic analysis of over-represented pathways in metastatic breast cancer identified ADAM22 as a top ranked member of the ECM-related druggable genome specific to brain metastases. ADAM22 was validated as an actionable target in in vitro, ex vivo and in patient tumour tissue (n = 843 patients). A peptide mimetic of the ADAM22 ligand LGI1, LGI1MIM, was designed in silico. The efficacy of LGI1MIM and its ability to penetrate the BBB were assessed in vitro, ex vivo and in brain metastasis BBB 3D biometric biohybrid models, respectively. Treatment with LGI1MIM in vivo inhibited disease progression, in particular the development of brain metastasis. Conclusion ADAM22 expression in advanced breast cancer supports development of breast cancer brain metastasis. Targeting ADAM22 with a peptide mimetic LGI1MIM represents a new therapeutic option to treat metastatic brain disease.

scholarly journals Predição computacional de alvos moleculares de um complexo metálico de rutênio com epiisopiloturina e óxido nítrico

2020 ◽  
Vol 11 (1) ◽  
pp. 42-48
Author(s):  
Joabe Lima Araújo ◽  
Gardênia Taveira Santos ◽  
Ruan Sousa Bastos ◽  
Francisco das Chagas Alves Lima ◽  
Jefferson Almeida Rocha
Keyword(s):  
In Silico ◽  
Ex Vivo ◽  
Óxido Nítrico

A Leishmaniose é uma doença infecciosa que ocasiona a morte de 26.000 a 65.000 pessoas anualmente, estima-se que no ano de 2019 houve 700.000 a 1 milhão de novos casos. Estes dados são preocupantes e está relacionado à falta de saneamento básico que favorece a proliferação dos vetores, além da ausência de medicamentos eficientes com mecanismos de ação alternativos e com menos efeitos colaterais. Em meio a essa necessidade de novos agentes inibitórios, este estudo teve como objetivo realizar uma predição computacional de alvos moleculares de Leishmania para um complexo metálico de rutênio com epiisopiloturina e óxido nítrico (Epiruno2). O processo de docking molecular foi realizado empregando-se o software Autodock Tools (ADT) versão 1.5.6. As proteínas alvos foram consideradas rígidas, enquanto que o Epiruno2 foi considerado flexível. A glicoproteína GP63 (1lml) representa mais de 1% da proteína total do parasito tendo em vista que a 1lml é uma metaloprotease que predomina grupos funcionais em seu sítio ativo, torna-se um alvo atrativo em estudos de atividade inibitória. O docking molecular entre o Epiruno2 e a 1lml resultou na melhor conformação de encaixe deste estudo, com energia de Gbinda de -8,05 Kcal.mol-1 e uma constante de inibição de 1,26 µM. Também foi observada a formação de quatro pontes de hidrogênio, demonstrando ser um forte candidato a fármaco antileishmania. Concluindo-se que o composto epiruno2 é clinicamente atrativo para estudos experimentais futuros ex vivo, in vitro e in vivo, pois seus resultados in sílico apresentaram boas interações moleculares para todas as proteínas alvo deste estudo.

scholarly journals Drug connectivity mapping and functional analysis reveals therapeutic small molecules that differentially modulate myelination

2020 ◽  
Author(s):  
F Pieropan ◽  
AD Rivera ◽  
G Williams ◽  
F Calzolari ◽  
AM Butt ◽  
...  
Keyword(s):  
Small Molecules ◽  
In Silico ◽  
Therapeutic Potential ◽  
Ex Vivo ◽  
Transcriptional Profiling ◽  
Drug Repurposing ◽  
Oligodendrocyte Progenitor Cells ◽  
Regulatory Pathways ◽  
Myelin Repair

AbstractOligodendrocytes are the myelin forming cells of the central nervous system (CNS) and are generated from oligodendrocyte progenitor cells (OPCs). Disruption or loss of oligodendrocytes and myelin has devastating effects on CNS function and integrity, which occurs in diverse neurological disorders, including Multiple Sclerosis (MS), Alzheimer’s disease (AD) and neuropsychiatric disorders. Hence, there is a need to develop new therapies that promote oligodendrocyte regeneration and myelin repair. A promising approach is drug repurposing, but most agents have potentially contrasting biological actions depending on the cellular context and their dose-dependent effects on intracellular regulatory pathways. Here, we have used a combined drug connectivity systems biology and neurobiological approach to identify compounds that exert positive and negative effects on oligodendroglia, depending on concentration. Notably, LY294002, a potent inhibitor of PI3K/Akt signalling, was the most highly ranked small molecule for both pro- and anti-oligodendroglial effects. We validated these in silico findings in multiple in vivo and ex vivo neurobiological models and demonstrate that low and high doses of LY294002 have a profoundly bipartite effect on the generation of OPCs and their differentiation into myelinating oligodendrocytes. Finally, we employed transcriptional profiling and signalling pathway activity assays to determine cell-specific mechanisms of action of LY294002 on oligodendrocytes and resolve optimal in vivo conditions required to promote myelin repair. These results demonstrate the power of multifactorial neurobiological and in silico strategies in determining the therapeutic potential of small molecules in neurodegenerative disorders.One-sentence summaryDrug discovery and CNS myelination

scholarly journals Removal of Protein-Bound Uremic Toxins Using Binding Competitors in Hemodialysis: A Narrative Review

Toxins ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 622
Author(s):  
Vaibhav Maheshwari ◽  
Xia Tao ◽  
Stephan Thijssen ◽  
Peter Kotanko
Keyword(s):  
Fatty Acids ◽  
In Silico ◽  
Membrane Separation ◽  
Ex Vivo ◽  
In Silico Analysis ◽  
Free Fraction ◽  
Uremic Toxins ◽  
Novel Method ◽  
Reactive Membrane

Removal of protein-bound uremic toxins (PBUTs) during conventional dialysis is insufficient. PBUTs are associated with comorbidities and mortality in dialysis patients. Albumin is the primary carrier for PBUTs and only a small free fraction of PBUTs are dialyzable. In the past, we proposed a novel method where a binding competitor is infused upstream of a dialyzer into an extracorporeal circuit. The competitor competes with PBUTs for their binding sites on albumin and increases the free PBUT fraction. Essentially, binding competitor-augmented hemodialysis is a reactive membrane separation technique and is a paradigm shift from conventional dialysis therapies. The proposed method has been tested in silico, ex vivo, and in vivo, and has proven to be very effective in all scenarios. In an ex vivo study and a proof-of-concept clinical study with 18 patients, ibuprofen was used as a binding competitor; however, chronic ibuprofen infusion may affect residual kidney function. Binding competition with free fatty acids significantly improved PBUT removal in pre-clinical rat models. Based on in silico analysis, tryptophan can also be used as a binding competitor; importantly, fatty acids or tryptophan may have salutary effects in HD patients. More chemoinformatics research, pre-clinical, and clinical studies are required to identify ideal binding competitors before routine clinical use.

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