Answer:Objective: To determine the combined effect of oxygen level and glucose concentration on cell viability, ATP production, and matrix synthesis of temporomandibular joint (TMJ) disc cells.
Design: TMJ disc cells were isolated from pigs aged 6-8 months and cultured in a monolayer. Cell cultures were preconditioned for 48 h with 0, 1.5, 5, or 25 mM glucose DMEM under 1%, 5%, 10%, or 21% O2 level, respectively. The cell viability was measured using the WST-1 assay. ATP production was determined using the Luciferin-Luciferase assay. Collagen and proteoglycan synthesis were determined by measuring the incorporation of [2, 3-(3)H] proline and [(35)S] sulfate into the cells, respectively.
Results: TMJ disc cell viability significantly decreased (P < 0.0001) without glucose. With glucose present, decreased oxygen levels significantly increased viability (P < 0.0001), while a decrease in glucose concentration significantly decreased viability (P < 0.0001). With glucose present, decreasing oxygen levels significantly reduced ATP production (P < 0.0001) and matrix synthesis (P < 0.0001). A decreased glucose concentration significantly decreased collagen synthesis (P < 0.0001). The interaction between glucose and oxygen was significant in regards to cell viability (P < 0.0001), ATP production (P = 0.00015), and collagen (P = 0.0002) and proteoglycan synthesis (P < 0.0001).
Conclusions: Although both glucose and oxygen are important, glucose is the limiting nutrient for TMJ disc cell survival. At low oxygen levels, the production of ATP, collagen, and proteoglycan are severely inhibited. These results suggest that steeper nutrient gradients may exist in the TMJ disc and it may be vulnerable to pathological events that impede nutrient supply.
Explanation: The evaluations a Mainly in the oganic responses
Answer:
Find the explanation below.
Explanation:
1. The study carried out by Saavedra and Silverman was aimed at evaluating the cause of button phobia, and the possibility of treating the button phobia using exposure-based, cognitive-behavioral therapy.
This study was necessitated by a phobia for buttons experienced by a nine-year-old boy. This feeling started at the age of five when the class performed an activity with buttons, and later a bowl filled with buttons fell on the boy. He began avoiding things with buttons.
2. The boy was treated by in vivo gradual exposure to buttons, and imagery exposure therapy. It was concluded that;
a. Imagery exposure therapy reduces the feeling of disgust which cause phobia.
b. Proper evaluation and incorporation of emotions are vital in the treatment of phobia.
Stability, consumption of the vehicle as well as the main purpose of the vehicle.
Answer:
D. its relevance to his argument regarding advances in peace preservation efforts
Explanation:
