scholarly journals Investigating the effect of micro-CT radiation dose on tumour growth in mice

2021 ◽  
Author(s):  
Kyle Foster

Micro-CT systems are used to obtain high-resolution CT images of small animals in vivo. The physical principals of x-ray CT require that the radiation dose delivered to the subject increase rapidly to achieve finer resolution while maintaining image quality. The effect of micro-CT imaging dose on tumour growth in mice was investigated in longitudinal imaging study. Four groups of tumour bearing mice were used: a control group that received no radiation, and three unique imaging groups that received low, medium and high dose scans respectively. The mice underwent their imaging protocols four times, once every four days starting the fourth day post inoculation. The results of an ANOVA test indicate the serial imaging did not cause a statistically significant difference in tumour growth among the four groups. The notion that serial imaging causes an effect equivalent to radiotherapy treatment can confidently be rejected (α + 0.1, β = 0.1).

2021 ◽  
Author(s):  
Kyle Foster

Micro-CT systems are used to obtain high-resolution CT images of small animals in vivo. The physical principals of x-ray CT require that the radiation dose delivered to the subject increase rapidly to achieve finer resolution while maintaining image quality. The effect of micro-CT imaging dose on tumour growth in mice was investigated in longitudinal imaging study. Four groups of tumour bearing mice were used: a control group that received no radiation, and three unique imaging groups that received low, medium and high dose scans respectively. The mice underwent their imaging protocols four times, once every four days starting the fourth day post inoculation. The results of an ANOVA test indicate the serial imaging did not cause a statistically significant difference in tumour growth among the four groups. The notion that serial imaging causes an effect equivalent to radiotherapy treatment can confidently be rejected (α + 0.1, β = 0.1).


Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1670 ◽  
Author(s):  
Wölfle-Roos JV ◽  
Katmer Amet B ◽  
Fiedler J ◽  
Michels H ◽  
Kappelt G ◽  
...  

Background: Uncemented implants are still associated with several major challenges, especially with regard to their manufacturing and their osseointegration. In this study, a novel manufacturing technique—an optimized form of precision casting—and a novel surface modification to promote osseointegration—calcium and phosphorus ion implantation into the implant surface—were tested in vivo. Methods: Cylindrical Ti6Al4V implants were inserted bilaterally into the tibia of 110 rats. We compared two generations of cast Ti6Al4V implants (CAST 1st GEN, n = 22, and CAST 2nd GEN, n = 22) as well as cast 2nd GEN Ti6Al4V implants with calcium (CAST + CA, n = 22) and phosphorus (CAST + P, n = 22) ion implantation to standard machined Ti6Al4V implants (control, n = 22). After 4 and 12 weeks, maximal pull-out force and bone-to-implant contact rate (BIC) were measured and compared between all five groups. Results: There was no significant difference between all five groups after 4 weeks or 12 weeks with regard to pull-out force (p > 0.05, Kruskal Wallis test). Histomorphometric analysis showed no significant difference of BIC after 4 weeks (p > 0.05, Kruskal–Wallis test), whereas there was a trend towards a higher BIC in the CAST + P group (54.8% ± 15.2%), especially compared to the control group (38.6% ± 12.8%) after 12 weeks (p = 0.053, Kruskal–Wallis test). Conclusion: In this study, we found no indication of inferiority of Ti6Al4V implants cast with the optimized centrifugal precision casting technique of the second generation compared to standard Ti6Al4V implants. As the employed manufacturing process holds considerable economic potential, mainly due to a significantly decreased material demand per implant by casting near net-shape instead of milling away most of the starting ingot, its application in manufacturing uncemented implants seems promising. However, no significant advantages of calcium or phosphorus ion implantation could be observed in this study. Due to the promising results of ion implantation in previous in vitro and in vivo studies, further in vivo studies with different ion implantation conditions should be considered.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 386
Author(s):  
Tung-Hu Tsai ◽  
Yu-Jen Chen ◽  
Li-Ying Wang ◽  
Chen-Hsi Hsieh

This study was performed to evaluate the interaction between conventional or high-dose radiotherapy (RT) and the pharmacokinetics (PK) of regorafenib in concurrent or sequential regimens for the treatment of hepatocellular carcinoma. Concurrent and sequential in vitro and in vivo studies of irradiation and regorafenib were designed. The interactions of RT and regorafenib in vitro were examined in the human hepatoma Huh-7, HA22T and Hep G2 cell lines. The RT–PK phenomenon and biodistribution of regorafenib under RT were confirmed in a free-moving rat model. Regorafenib inhibited the viability of Huh-7 cells in a dose-dependent manner. Apoptosis in Huh-7 cells was enhanced by RT followed by regorafenib treatment. In the concurrent regimen, RT decreased the area under the concentration versus time curve (AUC)regorafenib by 74% (p = 0.001) in the RT2 Gy × 3 fraction (f’x) group and by 69% (p = 0.001) in the RT9 Gy × 3 f’x group. The AUCregorafenib was increased by 182.8% (p = 0.011) in the sequential RT2Gy × 1 f’x group and by 213.2% (p = 0.016) in the sequential RT9Gy × 1 f’x group. Both concurrent regimens, RT2Gy × 3 f’x and RT9Gy × 3 f’x, clearly decreased the biodistribution of regorafenib in the heart, liver, lung, spleen and kidneys, compared to the control (regorafenib × 3 d) group. The concurrent regimens, both RT2Gy × 3 f’x and RT9Gy × 3 f’x, significantly decreased the biodistribution of regorafenib, compared with the control group. The PK of regorafenib can be modulated both by off-target irradiation and stereotactic body radiation therapy (SBRT).


Author(s):  
Meilinah Hidayat ◽  
Sijani Prahastuti ◽  
Estherolita Dewi ◽  
Dewi Safitri ◽  
Siti Farah Rahmawati ◽  
...  

ABSTRACTObjective: As an antiobesity therapy, combination extracts of Detam 1 soybean and Jati Belanda will be consumed for a long time; therefore, theirtoxicities to the liver need to be investigated. To determine the effect of subchronic toxicity test of combination of ethanol extract of Detam 1 soybean(EEDS) and ethanol extract of Jati Belanda (EEJB) on liver function with parameters: Alanine transaminase (ALT), macroscopic, and histopathologicalof liver.Methods: This study was conducted on 120 Wistar rats (60 males and 60 females), 90 days (treatment group) and 120 days (satellite group). Ratswere divided into six treatment groups (3 test materials, 1 control, and 2 satellites); each group included 10 males and 10 females.Results: ALT levels of treatment groups (low dose, medium, and high), both males and females were lower than the control group (p<0.05). Thetreatment groups demonstrated a good effects effect on liver function. Liver weight of all groups showed no significant difference compared with thecontrol group (p>0.05). Results of histopathological score interpretation of male and female liver rats of low dose groups were not disturbed; middledose groups were slightly disturbed and high dose groups were damaged. Satellite high doses of male groups were disrupted, while female groupswere not.Conclusion: The combination of EEDS and EEJB has a good effect on liver function, did not lead to change organ weight and at low doses did not causerenal histopathology damage in rats after 90 days administration.Keywords: Combination of soybean Jati Belanda, Toxicity subchronic test, Function, Weight, Histopathology, Liver.


2014 ◽  
Vol 39 (1) ◽  
pp. 30-34 ◽  
Author(s):  
SG Tulsani ◽  
N Chikkanarasaiah ◽  
S Bethur

Objectives: Biopure MTAD™, a new root canal irrigant has shown promising results against the most common resistant microorganism, E. faecalis, in permanent teeth. However, there is lack of studies comparing its antimicrobial effectiveness with NaOCl in primary teeth. The purpose of this study was to compare the in vivo antimicrobial efficacy of NaOCl 2.5% and Biopure MTAD™ against E. faecalis in primary teeth. Study design: Forty non vital single rooted primary maxillary anterior teeth of children aged 4-8 years, were irrigated either with NaOCl 2.5% (n=15), Biopure MTAD™ (n=15) and 0.9% Saline (n=10, control group). Paper point samples were collected at baseline (S1) and after chemomechanical preparation (S2) during the pulpectomy procedure. The presence of E. faecalis in S1 & S2 was evaluated using Real time Polymerase Chain Reaction. Results: Statistical significant difference was found in the antimicrobial efficacy of NaOCl 2.5 % and BioPure MTAD™ when compared to saline (p&gt;0.05). However, no statistical significant difference was found between the efficacies of both the irrigants. Conclusions: NaOCl 2.5% and BioPure MTAD™, both irrigants are equally efficient against E. faecalis in necrotic primary anterior teeth. MTAD is a promising irrigant, however clinical studies are required to establish it as ideal root canal irrigant in clinical practice.


2008 ◽  
Vol 74 (7) ◽  
pp. 1997-2003 ◽  
Author(s):  
Mathieu Millette ◽  
Gilbert Cornut ◽  
Claude Dupont ◽  
François Shareck ◽  
Denis Archambault ◽  
...  

ABSTRACT This study demonstrated the capacity of bacteriocin-producing lactic acid bacteria (LAB) to reduce intestinal colonization by vancomycin-resistant enterococci (VRE) in a mouse model. Lactococcus lactis MM19 and Pediococcus acidilactici MM33 are bacteriocin producers isolated from human feces. The bacteriocin secreted by P. acidilactici is identical to pediocin PA-1/AcH, while PCR analysis demonstrated that L. lactis harbors the nisin Z gene. LAB were acid and bile tolerant when assayed under simulated gastrointestinal conditions. A well diffusion assay using supernatants from LAB demonstrated strong activity against a clinical isolate of VRE. A first in vivo study was done using C57BL/6 mice that received daily intragastric doses of L. lactis MM19, P. acidilactici MM33, P. acidilactici MM33A (a pediocin mutant that had lost its ability to produce pediocin), or phosphate-buffered saline (PBS) for 18 days. This study showed that L. lactis and P. acidilactici MM33A increased the concentrations of total LAB and anaerobes while P. acidilactici MM33 decreased the Enterobacteriaceae populations. A second in vivo study was done using VRE-colonized mice that received the same inocula as those in the previous study for 16 days. In L. lactis-fed mice, fecal VRE levels 1.73 and 2.50 log10 CFU/g lower than those in the PBS group were observed at 1 and 3 days postinfection. In the P. acidilactici MM33-fed mice, no reduction was observed at 1 day postinfection but a reduction of 1.85 log10 CFU/g was measured at 3 days postinfection. Levels of VRE in both groups of mice treated with bacteriocin-producing LAB were undetectable at 6 days postinfection. No significant difference in mice fed the pediocin-negative strain compared to the control group was observed. This is the first demonstration that human L. lactis and P. acidilactici nisin- and pediocin-producing strains can reduce VRE intestinal colonization.


2007 ◽  
Vol 7 (3) ◽  
pp. 212-217 ◽  
Author(s):  
Sabaheta Hasić ◽  
Radivoj Jadrić ◽  
Emina Kiseljaković ◽  
Zakira Mornjaković ◽  
Mira Winterhalter-Jadrić

In our investigation, we used short-time model of myocardial infarction of rats induced by high dose of isoproterenol (ISP). We investigated cardiac troponin T blood level (cTnT) and histological characteristics of rat myocardium. ISP, single, intraperitoneal dose 250 mg/kg was given to male, adult, Wistar rats (n=12). Rats were distributed depending on their body weight in subgroups: ISP I (BW 260-280g) and ISP II (BW 250-400g). Control group (n=9) was treated with intraperitoneal dose of 0,95% NaCl. Cardiac TnT was measured by electrochemiluminiscence (ECLA) sandwich immunoassay in rat serum 4 hours after ISP application. Rats’ hearts were dissected and examined by qualitative histological method (HE). Statistical significance was set at 0,05. There was significant difference in cTnT of ISP II (p=0,0001) vs. control and ISP I (p<0,05) vs. control. Significant difference was beetween ISP I and ISP II subgroups (p<0.001). The accent of histological changes of myocardium was on nuclei of cell. Cells showed acydophilic changes and nuclei disappearance as signs of coagulative necrosis development. Extensivity of histological changes were different beetween ISP I and ISP II subgroup. Used dose of ISP induced development of myocardial necrosis in rats. Suben-docardial portion of myocardium was more vulnerability than subepicardial portion. Rats of ISP II had more extensive histological changes than these in ISP I. Administered doses of ISP enabled cTnT utilization as a marker of myocardial necrosis.


2015 ◽  
Vol 1 (1) ◽  
pp. 25
Author(s):  
Laila Fitrotuz Zahroh ◽  
Rahmawati Sri Praptiningsih ◽  
Moh. Baehaqi

Background: Oral mucosa ulceration which often occurs usually in the form of white-yellowish spot with concave surface, reddish edge and pain. Based on previous research, Aloe vera process anti-inflammation substance that could help quickening ulceration healing process. This research aims to know the effect of Aloe vera flesh extract on Male wistar rats oral mucosa ulceration in-vivo. Method: this research was quasi experimental research with the post-test only control group design using Male wistar rats as the testing animal. In the research, there were three treatment groups: The first groups which was given aquadest treatment, second groups with Aloe vera flesh extract, and third groups which was given chlorhexidine gluconate 0,2% treatment. The data collecting was based on histopathology observation concerning the increase of fibroblast quantity. Result: The research result based on comparison test among the three groups with One Way Anova showed that on Day 3th, the average quantity of fibroblast didn't have significant difference between the treatment group and control group positive that was p>0,05, meanwhile on Day 7th every group showed significant difference p<0,05. Conclusion: It concluded that Aloe vera flesh extract has influence on the healing of Male wistar rats oral mucosa ulceration as shown by fibroblast increasing quantity.


2021 ◽  
Vol 15 (1) ◽  
pp. 532-538
Author(s):  
Mostafa M. El-Bialy ◽  
Magdy M. Ali ◽  
Engy M. Kataia ◽  
Reham S. El Nemr ◽  
Reham Hassan

Background: The interaction between the root canal system and the oral cavity caused by iatrogenic perforations significantly affects the treatment outcome and tooth survival. Objectives: This study was directed to compare the biocompatibility of an experimental tricalcium phosphate cement versus biodentine and mineral Trioxide aggregate used for furcation perforation repair in dogs. Methods: Perforations were done in 60 teeth (premolars and molars) of six adult dogs. Animals were divided randomly into 3 equal groups of 2 animals each according to the post-operative evaluation period of 1 week, 1 month, and 3-months. Each group was further subdivided into 4 subgroups according to either being repaired with the experimental tricalcium phosphate cement (n=6), or Biodentine (n=6), Mineral Trioxide Aggregate (MTA) (n=6), and positive control(n=2). After evaluation periods, tissue blocks were harvested and histologically examined. Results: No statistically significant difference was found regarding bone deposition scores and inflammatory reaction in the three groups after 1 week, 1 month, or 3 months. All three groups showed a statistically significant difference between all three time periods. Regardless of the repair material used, inflammation scores at 1-week showed the highest scores, decreasing over time except for the control group. Conclusion: The experimental material could be considered as a successful treatment option for repairing furcation perforation.


Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2520 ◽  
Author(s):  
Eun-Bin Bae ◽  
Ji-Hyun Yoo ◽  
Sung-In Jeong ◽  
Min-Su Kim ◽  
Youn-Mook Lim ◽  
...  

This study aimed to evaluate the titanium (Ti) implants coated with collagen type Ⅰ crosslinked using gamma-irrigation or glutaraldehyde (GA). The in vitro surface observations, quantification assay, and cell studies using human mesenchymal stem cells (hMSCs) were conducted. For in vivo experiments, the implants were divided into three groups and inserted into the rat tibias: control group (non-treated Ti implant), GA group (Ti implants coated with GA-crosslinked collagen) and 25 kGy group (Ti implants coated with gamma-radiation-crosslinked collagen at dose of 25 kGy). The animals were sacrificed at 4 weeks after implantation and the tissue sections were obtained. New bone volume (mm3) and bone-to-implant contact (BIC, %) within the region of interest (ROI) was measured. The in vitro results showed the highest osteogenic differentiation and levels of osteogenesis-related gene expressions in the 25 kGy group without cytotoxicity. The new bone volume of GA group was significantly higher than the control (p < 0.05). In the result of the BIC, the 25 kGy group was significantly higher than the control (p < 0.05). However, there was no significant difference between the experimental groups. Within the limitations of this study, Ti implant coated with gamma-radiation-crosslinked collagen has potential utility without side effects from chemical agents.


Sign in / Sign up

Export Citation Format

Share Document