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.
The effect of multi-step tempering on retained austenite content and mechanical properties of low alloy steel used in the forged cold back-up roll was investigated.Microstructural evolutions were ...characterized by optical microscope,X-ray diffraction,scanning electron microscope and Feritscope,while the mechanical properties were determined by hardness and tensile tests.The results revealed that the content of retained austenite decreased by about 2% after multi-step tempering.However,the content of retained austenite increased from 3.6% to 5.1% by increasing multi-step tempering temperature.The hardness and tensile strength increased as the austenitization temperature changed from 800 to 920 ℃,while above 920 ℃,hardness and tensile strength decreased.In addition,the maximum values of hardness,ultimate and yield strength were obtained via triple tempering at 520 ℃,while beyond 520 ℃,the hardness,ultimate and yield strength decreased sharply.
► The effect of Ca and Zn addition on Mg–Ca and Mg–Ca–Zn were investigated. ► Ca and Zn addition decreased solid fraction at coherency point. ►
T
N–
T
DCP increased by adding Ca and Zn in Mg–Ca and ...Mg–Ca–Zn, respectively. ► Three reactions were detected when Zn/Ca atomic ratio less than 1.25 in Mg–Ca–Zn. ► A new peak Mg
51Zn
20 was identified in Mg–0.5Ca–9Zn in addition of other peaks.
This research described the identification phases by thermal analysis and microscopy inspection of Mg–
xCa and Mg–0.5%Ca–
xZn alloys that were solidified at slow cooling rate. Analysis of cooling curve after Ca addition shows the evolution of the Mg
2Ca intermetallic phase at around 520
°C in addition to α-Mg phase. First derivative curves of alloys after the addition of Zn to Mg–0.5Ca alloy reveals three peaks related to α-Mg, Mg
2Ca and Ca
2Mg
6Zn
3 for alloys that have Zn/Ca atomic ratio less than 1.23. The peak of Mg
2Ca reaction on the first derivative curves disappeared for alloys containing Zn/Ca ratio more than 1.23. A new peak was also observed at 330
°C for Mg–0.5Ca–9Zn which was identified as Mg
51Zn
20. Solid fraction at coherency point decreased with increasing Ca and Zn elements. However, coherency time and difference between the nucleation and coherency temperatures (
T
N–
T
DCP) increased by adding Ca and Zn in Mg–Ca and Mg–Ca–Zn systems.
The influence of hydrofluoric acid (HF) treatment on the corrosion behavior of the Mg-0.5Ca alloys was investigated by immersion specimen in sodium hydroxide and HF solutions with various ...concentrations and durations at room temperature. Microstructural evolutions of the specimens were characterized by atomic force microscopy, X-ray diffraction, field-emission scanning electron microscopy. The corrosion resistance was examined through potentiodynamic polarization and immersion test in Kokubo solution. The results revealed that the fluoride treated Mg-0.5Ca alloys produced by immersion in 40% HF provided more uniform, dense and thicker coating layer (12.6 μm) compared with the 35% HF treated specimen. The electrochemical test showed that the corrosion resistance of fluoride treated specimen was 35 times higher compared with the untreated Mg-0.5Ca alloy specimen in Kokubo solution. In vitro degradation rate of the fluoride treated specimens was much lower than untreated Mg-0.5Ca alloy in Kokubo solution. After immersion test the surface of 40% HF treated sample showed a few corrosion dots, while untreated specimens were fully covered by corrosion products and delamination. Fluoride treated Mg-0.5Ca alloy with 40% HF is a promising candidate as biodegradable implants due to its low degradation kinetics and good biocompatibility.
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