Cancer recurrence is often associated with the acquisition of radioresistance by cancer tissues due to failure in radiotherapy. The underlying mechanism leading to the development of acquired ...radioresistance in the EMT6 mouse mammary carcinoma cell line and the potential pathway involved was investigated by comparing differential gene expressions between parental and acquired radioresistance cells. EMT6 cell line was exposed to 2 Gy/per cycle of gamma-ray and the survival fraction between EMT6-treated and parental cells was compared. EMT6
(acquired radioresistance) cells was developed after 8 cycles of fractionated irradiation. The development of EMT6
cells was confirmed with further irradiation at different doses of gamma-ray, and both the survival fraction and migration rates were measured. Higher survival fraction and migration rates were obtained in EMT6
cells after exposure to 4 Gy and 8 Gy gamma-ray irradiations compared to their parental cells. Gene expression between EMT6
and parental cells was compared, and 16 genes identified to possess more than tenfold changes were selected and validated using RT-PCR. Out of these genes, 5 were significantly up-regulated i.e., IL-6, PDL-1, AXL, GAS6 and APCDD1. Based on pathway analysis software, the development of acquired radioresistance in EMT6
was hypothesized through JAK/STAT/PI3K pathway. Presently, CTLA-4 and PD-1 were determined to be associated with JAK/STAT/PI3K pathway, where both their expressions were significantly increased in EMT6
compared to parental cells in the 1st, 4th and 8th cycle of radiation. As a conclusion, the current findings provided a mechanistic platform for the development of acquired radioresistance in EMT6
through overexpression of CTLA-4 and PD-1, and novel knowledge on therapeutic targets for recurrent radioresistant cancers.
Abstract
Background
Intrapleural fibrinolytic therapy (IPFT) is one of the treatment options for complex pleural effusion. In this study, the IPFT agent used was alteplase, a tissue plasminogen ...activator (t-PA). This study aims to determine the difference in the outcome of patients with complex pleural effusion between IPFT and surgery in terms of radiological improvement, inflammatory parameters, length of stay, and post-intervention complications.
Methods
A retrospective review of patients with complex pleural effusion treated at Universiti Kebangsaan Malaysia Medical Center from January 2012 to August 2020 was performed. Patient demographics, chest imaging, drainage chart, inflammatory parameters, length of hospital stay, and post-intervention and outcome were analyzed.
Results
Fifty-eight patients were identified (surgical intervention,
n
= 18; 31% and IPFT,
n
= 40, 69%). The mean age was 51.7 ± 18.2 years. Indication for surgical intervention was pleural infection (
n
= 18; 100%), and MPE (
n
= 0). Indications for IPFT was pleural infection (
n
= 30; 75%) and MPE (
n
= 10; 25%). The dosages of t-PA were one to five doses of 2–50 mg. The baseline chest radiograph in the IPFT group was worse than in the surgical intervention group. (119.96 ± 56.05 vs. 78.19 ± 55.6;
p
= 0.029) At week 1, the radiological success rate for IPFT and surgical intervention were 27% and 20%, respectively, and at weeks 4–8, the success rate was 56% and 80% respectively. IPFT was associated with lesser complications; fever (17.5%), chest pain (10%), and non-life-threatening bleeding (5%).
Conclusion
IPFT was comparable to surgery in radiological outcome, inflammatory parameters, and length of stay with lesser reported complications.
This study aims to analyze students' self-efficacy using STEM-based Project Based Learning (PjBL) learning models. The research design uses a quasi experiment consisting of two groups, namely the ...experimental group and the control group. The experimental group got the treatment in the form of STEM PjBL learning while the control class used conventional learning. The self-efficacy instruments used in this study were divided into five categories. Quantitative data obtained from the study were analyzed using an independent sample t-test to see whether there were differences in self-efficacy in the two classes. The effectiveness of the treatment given in both classes was analyzed using the average Gain (N-Gain) value obtained by both classes. The results showed that the students' self-efficacy increased after the learning of STEM PjBL was given. In addition, the increase in the average N-Gain score obtained by the experimental group is better than the control group.Abstrak: Penelitian ini bertujuan menganalisis efikasi diri siswa menggunakan model pembelajaran Project Based Learning (PjBL) berbasis STEM. Desain penelitian menggunakan eksperimen kuasi yang terdiri dari dua kelompok yaitu kelompok eksperimen dan kelompok kontrol. Kelompok eksperimen mendapatkan treatment berupa pembelajaran PjBL STEM sedangkan kelompok kontrol menggunakan pembelajaran konvensional. Instrumen efikasi diri yang digunakan pada penelitian ini terbagi menjadi lima kategori. Data kuantitatif yang diperoleh dari penelitian dianalisis menggunakan independent sample t – test untuk mengetahui ada tidaknya perbedaan efikasi diri pada kedua kelompok. Efektivitas treatment yang diberikan pada kedua kelompok dianalisis menggunakan nilai Gain (N – Gain) rata – rata yang dicapai kedua kelompok. Berdasarkan analisis yang dilakukan, diperoleh bahwa efikasi diri siswa mengalami kenaikan setelah pembelajaran PjBL STEM diberikan. Selain itu, peningkatan skor rata – rata N-Gain yang diperoleh kelompok eksperimen lebih baik dibandingkan kelompok kontrol.
► Evaluation of corrosion mechanism and solidification behavior of Mg–
xCa. ► Microstructure of Mg–
xCa alloys were characterized by XRD, OM, SEM and EDS. ► Thermal analysis of alloys was carried out ...by computer aided cooling curve analysis. ► The addition of Ca content increase Mg
2Ca lead to increasing corrosion rate.
The calcium content in binary Mg–
xCa alloys affects the microstructure, corrosion and solidification behavior of the alloys. In this study, binary Mg–
xCa alloys with various Ca contents from 0.5 to 10
wt.% were produced by casting process. Microstructural evolutions were characterized by optical microscopy, X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. Solidification behavior was assessed via two thermocouple thermal analysis method. The corrosion resistance was examined in vitro by potentiodynamic polarization and immersion test in Kokubo solution at room temperature. The results revealed that the grain size and dendrite cell size decreased significantly with rising Ca content, whilst the content of Mg
2Ca intermetallic phase in grain boundaries increased with increasing Ca content. Potentiodynamic polarization tests in simulated body fluid (SBF) indicated that corrosion rates of Mg–
xCa alloy increased significantly with rising Ca content. Immersion tests in Kokubo solution also showed that dissolution rate of Mg–
xCa alloy increased with increasing Mg
2Ca content which lead to an increase in pH value. It was observed that corrosion damage in specimens with lower Ca content was more moderate and uniform than higher Ca content. Thermal analysis results showed that the fraction of primary α-Mg at dendrite coherency point
(
f
α
DCP
)
decreased with increasing Ca content but the liquid fraction
f
L increased causing the rise in eutectic Mg
2Ca intermetallic phase in grain boundaries, thus increasing the corrosion rate. Our analyses showed that Mg–0.5Ca alloy is a promising alloy to be used as biodegradable implants.
PDF
