Radiofrequency Ablation by a 21-Gauge Internally Cooled Electrode: Ex Vivo and In Vivo Evaluation by Rat Liver

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.

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Perivascular vital cells in the ablation center after multibipolar radiofrequency ablation in an in vivo porcine model

Scientific Reports ◽

10.1038/s41598-021-93406-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

F. G. M. Poch ◽

C. A. Neizert ◽

B. Geyer ◽

O. Gemeinhardt ◽

S. M. Niehues ◽

...

Keyword(s):

Radiofrequency Ablation ◽

Early Stage ◽

Pringle Maneuver ◽

Vessel Diameter ◽

Inflow Occlusion ◽

White Zone ◽

Cell Vitality ◽

Internally Cooled ◽

Hepatic Vessels

AbstractMultibipolar radiofrequency ablation (RFA) is an advanced ablation technique for early stage hepatocellular carcinoma and liver metastases. Vessel cooling in multibipolar RFA has not been systematically investigated. The objective of this study was to evaluate the presence of perivascular vital cells within the ablation zone after multibipolar RFA. Multibipolar RFA were performed in domestic pigs in vivo. Three internally cooled bipolar RFA applicators were used simultaneously. Three experimental settings were planned: (1) inter-applicator-distance: 15 mm; (2) inter-applicator-distance: 20 mm; (3) inter-applicator-distance: 20 mm with hepatic inflow occlusion (Pringle maneuver). A vitality staining was used to analyze liver cell vitality around all vessels in the ablation center with a diameter > 0.5 mm histologically. 771 vessels were identified. No vital tissue was seen around 423 out of 429 vessels (98.6%) situated within the central white zone. Vital cells could be observed around major hepatic vessels situated adjacent to the ablation center. Vessel diameter (> 3.0 mm; p < 0.05) and low vessel-to-ablation-center distance (< 0.2 mm; p < 0.05) were identified as risk factors for incomplete ablation adjacent to hepatic vessels. The vast majority of vessels, which were localized in the clinically relevant white zone, showed no vital perivascular cells, regardless of vessel diameter and vessel type. However, there was a risk of incomplete ablation around major hepatic vessels situated directly within the ablation center. A Pringle maneuver could avoid incomplete ablations.

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Effect of Processing on Fish Protein Antigenicity and Allergenicity

Foods ◽

10.3390/foods10050969 ◽

2021 ◽

Vol 10 (5) ◽

pp. 969

Author(s):

Xingyi Jiang ◽

Qinchun Rao

Keyword(s):

Fish Species ◽

Protein Denaturation ◽

Ex Vivo ◽

Protein Solubility ◽

Future Research ◽

Food Protein ◽

In Vivo Evaluation ◽

Fish Allergy

Fish allergy is a life-long food allergy whose prevalence is affected by many demographic factors. Currently, there is no cure for fish allergy, which can only be managed by strict avoidance of fish in the diet. According to the WHO/IUIS Allergen Nomenclature Sub-Committee, 12 fish proteins are recognized as allergens. Different processing (thermal and non-thermal) techniques are applied to fish and fishery products to reduce microorganisms, extend shelf life, and alter organoleptic/nutritional properties. In this concise review, the development of a consistent terminology for studying food protein immunogenicity, antigenicity, and allergenicity is proposed. It also summarizes that food processing may lead to a decrease, no change, or even increase in fish antigenicity and allergenicity due to the change of protein solubility, protein denaturation, and the modification of linear or conformational epitopes. Recent studies investigated the effect of processing on fish antigenicity/allergenicity and were mainly conducted on commonly consumed fish species and major fish allergens using in vitro methods. Future research areas such as novel fish species/allergens and ex vivo/in vivo evaluation methods would convey a comprehensive view of the relationship between processing and fish allergy.

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Pivotal role of Acitretin nanovesicular gel for effective treatment of psoriasis: ex vivo–in vivo evaluation study

International Journal of Nanomedicine ◽

10.2147/ijn.s156412 ◽

2018 ◽

Vol Volume 13 ◽

pp. 1059-1079 ◽

Cited By ~ 17

Author(s):

Irhan Abu Hashim ◽

Noha Abo El-Magd ◽

Ahmed El-Sheakh ◽

Mohammed Hamed ◽

Abd El-Gawad Abd El-Gawad

Keyword(s):

Effective Treatment ◽

Ex Vivo ◽

Evaluation Study ◽

Pivotal Role ◽

In Vivo Evaluation

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In Vitro and In Vivo Evaluation of Human Adenovirus Type 49 as a Vector for Therapeutic Applications

Viruses ◽

10.3390/v13081483 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1483

Author(s):

Emily A. Bates ◽

John R. Counsell ◽

Sophie Alizert ◽

Alexander T. Baker ◽

Natalie Suff ◽

...

Keyword(s):

Viral Vector ◽

Ex Vivo ◽

Human Adenovirus ◽

Adenovirus Type ◽

Cell Types ◽

In Vivo Evaluation ◽

In Vivo Biodistribution ◽

Adenovirus Type 5

The human adenovirus phylogenetic tree is split across seven species (A–G). Species D adenoviruses offer potential advantages for gene therapy applications, with low rates of pre-existing immunity detected across screened populations. However, many aspects of the basic virology of species D—such as their cellular tropism, receptor usage, and in vivo biodistribution profile—remain unknown. Here, we have characterized human adenovirus type 49 (HAdV-D49)—a relatively understudied species D member. We report that HAdV-D49 does not appear to use a single pathway to gain cell entry, but appears able to interact with various surface molecules for entry. As such, HAdV-D49 can transduce a broad range of cell types in vitro, with variable engagement of blood coagulation FX. Interestingly, when comparing in vivo biodistribution to adenovirus type 5, HAdV-D49 vectors show reduced liver targeting, whilst maintaining transduction of lung and spleen. Overall, this presents HAdV-D49 as a robust viral vector platform for ex vivo manipulation of human cells, and for in vivo applications where the therapeutic goal is to target the lung or gain access to immune cells in the spleen, whilst avoiding liver interactions, such as intravascular vaccine applications.

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