scholarly journals Design Collimator and Dosimetry of in Vitro and in Vivo Test Using MCNP-X Code

2016 ◽  
Vol 1 (1) ◽  
pp. 14
Author(s):  
Sri Yuniarti ◽  
Yohannes Sardjono ◽  
Bilalodin Bilalodin

Studies were carried out to collimator modelling and dosimetry BNCT of in vitro and in vivo test using MCNP-X code. Collimator modelling performed to obtain neutron beam as required by the International Atomic Energy Agency (IAEA). Dosimetry calculations performed to obtain the results of the dose calculation (dosimetry) in the application of BNCT.  Collimator modelling and dosimetry simulations performed with MCNPX program. Neutron sources used for simulation, namely cyclotrons HM-30, energy 30 MeV, the current is 1.1 mA. Collimator modelling utilizes to program MCNPX covers cells target as beryllium, collimator wall (reflector), moderate, filter, gamma-ray shielding, and aperture. The simulation results of the modelling are Φ<sub>epi </sub>1.02241x10<sup>10</sup> n/cm2 s, D<sub>f</sub>/Φ<sub>epi </sub>2.36487x10<sup>-11 </sup>Gy-cm<sup>2</sup>/n, D<sub>γ</sub>/Φ<sub>epi</sub> 4.68416x10<sup>-12</sup> Gy-cm<sup>2</sup>/n, Φ<sub>th</sub>/Φ<sub>epi </sub>3.76285x10<sup>-01</sup>, J/Φ<sub>epi </sub>8.37678x10<sup>3</sup>. Based on the calculation of the dose rate that has been done, the result that the optimal dose rate at a depth of 1cm.

1992 ◽  
Vol 67 (06) ◽  
pp. 660-664 ◽  
Author(s):  
Virgilio Evangelista ◽  
Paola Piccardoni ◽  
Giovanni de Gaetano ◽  
Chiara Cerletti

SummaryDefibrotide is a polydeoxyribonucleotide with antithrombotic effects in experimental animal models. Most of the actions of this drug have been observed in in vivo test models but no effects have been reported in in vitro systems. In this paper we demonstrate that defibrotide interferes with polymorphonuclear leukocyte-induced human platelet activation in vitro. This effect was not related to any direct interaction with polymorphonuclear leukocytes or platelets, but was due to the inhibition of cathepsin G, the main biochemical mediator of this cell-cell cooperation. Since cathepsin G not only induces platelet activation but also affects some endothelial cell functions, the anticathepsin G activity of defibrotide could help to explain the antithrombotic effect of this drug.


Biomolecules ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 360
Author(s):  
Pieterjan Debie ◽  
Noemi B. Declerck ◽  
Danny van Willigen ◽  
Celine M. Huygen ◽  
Bieke De Sloovere ◽  
...  

Intraoperative guidance using targeted fluorescent tracers can potentially provide surgeons with real-time feedback on the presence of tumor tissue in resection margins. To overcome the limited depth penetration of fluorescent light, combining fluorescence with SPECT/CT imaging and/or gamma-ray tracing has been proposed. Here, we describe the design and preclinical validation of a novel bimodal nanobody-tracer, labeled using a “multifunctional single attachment point” (MSAP) label, integrating a Cy5 fluorophore and a diethylenetriaminepentaacetic acid (DTPA) chelator into a single structure. After conjugation of the bimodal MSAP to primary amines of the anti-HER2 nanobody 2Rs15d and 111In-labeling of DTPA, the tracer’s characteristics were evaluated in vitro. Subsequently, its biodistribution and tumor targeting were assessed by SPECT/CT and fluorescence imaging over 24 h. Finally, the tracer’s ability to identify small, disseminated tumor lesions was investigated in mice bearing HER2-overexpressing SKOV3.IP1 peritoneal lesions. [111In]In-MSAP.2Rs15d retained its affinity following conjugation and remained stable for 24 h. In vivo SPECT/CT and fluorescence images showed specific uptake in HER2-overexpressing tumors with low background. High tumor-to-muscle ratios were obtained at 1h p.i. and remained 19-fold on SPECT/CT and 3-fold on fluorescence images over 24 h. In the intraperitoneally disseminated model, the tracer allowed detection of larger lesions via nuclear imaging, while fluorescence enabled accurate removal of submillimeter lesions. Bimodal nuclear/fluorescent nanobody-tracers can thus be conveniently designed by conjugation of a single-molecule MSAP-reagent carrying a fluorophore and chelator for radioactive labeling. Such tracers hold promise for clinical applications.


1998 ◽  
Vol 26 (5) ◽  
pp. 629-634
Author(s):  
Emiliana Falcone ◽  
Edoardo Vignolo ◽  
Livia Di Trani ◽  
Simona Puzelli ◽  
Maria Tollis

A reverse transcriptase polymerase chain reaction (RT-PCR) assay specific for identifying avian infectious bronchitis virus (IBV) in poultry vaccines, and the serological response to IBV induced by the inoculation of chicks with a Newcastle disease vaccine spiked with the Massachusetts strain of IBV, were compared for their ability to detect IBV as a contaminant of avian vaccines. The sensitivity of the IBV-RT-PCR assay provided results which were at least equivalent to the biological effect produced by the inoculation of chicks, allowing this assay to be considered a valid alternative to animal testing in the quality control of avian immunologicals. This procedure can easily be adapted to detect a number of contaminants for which the in vivo test still represents the only available method of detection.


Biomedicines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 181
Author(s):  
Loredana G. Marcu ◽  
Eva Bezak ◽  
Dylan D. Peukert ◽  
Puthenparampil Wilson

FLASH radiotherapy, or the administration of ultra-high dose rate radiotherapy, is a new radiation delivery method that aims to widen the therapeutic window in radiotherapy. Thus far, most in vitro and in vivo results show a real potential of FLASH to offer superior normal tissue sparing compared to conventionally delivered radiation. While there are several postulations behind the differential behaviour among normal and cancer cells under FLASH, the full spectra of radiobiological mechanisms are yet to be clarified. Currently the number of devices delivering FLASH dose rate is few and is mainly limited to experimental and modified linear accelerators. Nevertheless, FLASH research is increasing with new developments in all the main areas: radiobiology, technology and clinical research. This paper presents the current status of FLASH radiotherapy with the aforementioned aspects in mind, but also to highlight the existing challenges and future prospects to overcome them.


2015 ◽  
Vol 15 (1) ◽  
pp. 17
Author(s):  
Endang Sri Ratna ◽  
Kemas Usman ◽  
Indah Arastuti ◽  
Dadan Hindayana

Effect of gamma irradiation [60Co] against Bactrocera carambolae Drew & Hancock in vitro and in vivo. Bactrocera carambolae Drew & Hancock is one of the most important pests on guava fruit. According to a quarantine regulation in export-import commodities, irradiation treatment is a suitable methods for eradicating infested organism, which is relatively safe for the environment. The aim of this research was to determine mortality doses and an effective dose of [60Co] gamma ray irradiation for the eradication purpose, and its implication on the survival of fruit fly B. carambolae. Two irradiation methods of in vitro dan in vivo were carried out, by exposing egg and 3rd instar larvae of B. carambolae obtained from the laboratory reared insect. Eleven doses of gamma ray irradiation of 0, 30, 50, 75, 100, 125, 150, 175, 200, 300, 450, and 600 Gy were applied, respectively. The level of 99% fruit fly mortality was estimated by the value of LD99 using probit analysis and the number of larvae, pupae and adult survival were evaluated by analysis of variance (ANOVA), and the means compared by Tukey’s test, at 5% of significance level. These result showed that the effective lethal dose (LD99) of irradiation that could be successful to eradicate eggs and 3rd instar larvae in vitro were 2225 and 2343 Gy and in vivo were 3165 dan 3177 Gy, respectively. Almost all of the treated larvae survived and developed to pupae, therefore only the minimum irradiation dose of 30 Gy allowed the pupae to develop into adults.


2020 ◽  
Vol 8 (10) ◽  
pp. 285-291
Author(s):  
Budy Rahmat ◽  
Dedi Natawijaya ◽  
Endang Surahman

Liquid smoke is known to contain compounds that can control plant disease pathogens. This study aims to produce wood-waste liquid smoke and determine its effectiveness as a fungicide on plant pathogens. This research was conducted in two experimental stages, namely: (i) in vitro test as a preliminary test of the effectiveness of teak waste liquid smoke at concentrations of 0, 0.5, 1, 1.5, 2, and 2.5%; and (ii) in vivo test was arranged in randomized block design consisting of seven levels of liquid smoke concentration, namely 0, 1, 2, 3, 4, 5, and 6%, each of which was repeated four times. The results showed that the pyrolysis of 1 kg of wood waste was produced with the proportions of liquid smoke, charcoal and tar, respectively: 312 mL, 31 g, 367 g and the uncondensed gases. Treatment of liquid smoke in the in vivo test showed that a concentration of 1 to 2.5% liquid smoke was able to suppress the growth of the pathogenic fungus Sclerotium rolfsii 100%. The treatment of liquid smoke in the in vivo test showed an effect on inhibition of the growth diameter of fungal colonies, suppressing the disease occurance, and suppressing the lesion diameter.


Pharmaceutics ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 416 ◽  
Author(s):  
Schneider ◽  
Koziolek ◽  
Weitschies

More than 50 years ago, the first concepts for gastroretentive drug delivery systems were developed. Despite extensive research in this field, there is no single formulation concept for which reliable gastroretention has been demonstrated under different prandial conditions. Thus, gastroretention remains the holy grail of oral drug delivery. One of the major reasons for the various setbacks in this field is the lack of predictive in vitro and in vivo test methods used during preclinical development. In most cases, human gastrointestinal physiology is not properly considered, which leads to the application of inappropriate in vitro and animal models. Moreover, conditions in the stomach are often not fully understood. Important aspects such as the kinetics of fluid volumes, gastric pH or mechanical stresses have to be considered in a realistic manner, otherwise, the gastroretentive potential as well as drug release of novel formulations cannot be assessed correctly in preclinical studies. This review, therefore, highlights the most important aspects of human gastrointestinal physiology and discusses their potential implications for the evaluation of gastroretentive drug delivery systems.


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