instruction:
Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
question:
Context: Photodynamic therapy (PDT) is linked with oxidative damage of biomolecules causing significant impairment of essential cellular functions that lead to cell death. It is the reason why photodynamic therapy has found application in treatment of different oncological, cardiovascular, skin and eye diseases. Efficacy of PDT depends on combined action of three components; sensitizer, light and oxygen. In the present study, we examined whether higher partial pressure of oxygen increases lethality in HeLa cell lines exposed to light in the presence of chloraluminium phthalocyanine disulfonate (ClAlPcS2).', 'ClAlPcS2- sensitized HeLa cells incubated under different oxygen conditions were exposed to PDT. Production of singlet oxygen ((1)O2) and other forms of reactive oxygen species (ROS) as well as changes in mitochondrial membrane potential were determined by appropriately sensitive fluorescence probes. The effect of PDT on HeLa cell viability under different oxygen conditions was quantified using the standard methylthiazol tetrazolium (MTT) test.', 'At the highest oxygen concentration of 28 ± 2 mg/l HeLa cells were significantly more sensitive to light-activated ClAlPcS2 (EC50=0.29 ± 0.05 μM) in comparison to cells incubated at lower oxygen concentrations of 8 ± 0.5 and 0.5 ± 0.1 mg/l, where the half maximal effective concentration was 0.42 ± 0.06 μM and 0.94 ± 0.14 μM, respectively. Moreover, we found that the higher presence of oxygen is accompanied with higher production of singlet oxygen, a higher rate of type II photodynamic reactions, and a significant drop in the mitochondrial membrane potential.
Answer: These results demonstrate that the photodynamic effect in cervical cancer cells utilizing ClAlPcS2 significantly depends on oxygen level.
answer:
Does high oxygen partial pressure increase photodynamic effect on HeLa cell lines in the presence of chloraluminium phthalocyanine?


question:
Context: The objective of this study was to investigate the long-term effect of intraoperative application of steroid suspension and coating of the electrode contacts with a thin film of iridium oxide on the intracochlear impedance development after cochlear implantation and on the impedance difference before and after stimulation.', 'Time-dependent development of intracochlear impedances was investigated in 4 different groups of adult patients up to 4 years after implantation. Additionally, during rehabilitation period just after first fitting, impedances before and after stimulation were measured as to investigate the influence of electrical stimulation on the impedances. Results from standard Nucleus 24 Contour (control), standard Nucleus 24 Contour with intraoperative application of steroids, iridium-coated Nucleus 24 Contour, and iridium-coated Nucleus 24 Contour with intraoperative application of steroids were compared.', 'Steroid application reduced impedances significantly throughout the observation period of up to 4 years after implantation. Iridium oxide coating had no effect. Differences between the groups were mainly found on the basal and middle parts of the cochlea, but not close to the tip of the array, also indicating that postoperative fibrous tissue growth is stronger in the basal region of the cochlea. Group mean values of the stimulation effect were not influenced by the different treatments. Nevertheless, only in both steroid-treated groups a correlation between the impedance before stimulation and the stimulation effect was found.
Answer: Although the differences between control and steroid-treated groups decrease with time, single intraoperative intracochlear steroid deposition was proven to lower postoperative impedances during first 3 to 4 years after implantation probably because of reduction of fibrous tissue growth.
answer:
Do the long-term effects of modified electrode surfaces and intracochlear corticosteroids on postoperative impedances in cochlear implant patients?


question:
Context: The purpose of this study was to evaluate the role of capsular closure after hip arthroscopy in reduction of the incidence of heterotopic ossification (HO).', 'One hundred (50 study group, 50 control group) consecutive hip arthroscopy procedures with radiographic follow-up of more than 9 weeks were included in the study. The study group consisted of 50 patients in whom capsular closure with 2 No. 1 polydioxanone (PDS) sutures was performed, and a control group consisted of 50 patients in whom the capsule remained open after capsulotomy. HO was assessed by radiographs using the Brooker classification. Statistical analysis of the data was carried out with the χ-square or Fisher exact test and Student t test, when appropriate, at a significance level of .05.', 'Thirty-six (36%) patients had radiographic evidence of postoperative HO (14 patients in the capsular closure group). No significant difference was found regarding sex, side of operation, age, or HO rate between the study and the control groups (P = .778, P = .123, P = .744, and P = .144, respectively). Furthermore, no significant difference was found in the rate of HO with potential clinical significance (Brooker classification > I) between the control and study groups (P = .764).
Answer: Capsular closure did not seem to alter the rate of HO when compared with a control group of patients in whom the capsulotomy was not repaired.
answer:

Does capsular closure affect development of heterotopic ossification after hip arthroscopy?