Given a passage, 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.

Q: To determine whether activin A concentrations are altered in chronic fetal hypoxemia and intrauterine fetal growth restriction (IUGR).', 'In vivo animal experimental model.', 'Department of Physiology, Monash University.', 'Chronically catherised fetal sheep in late pregnancy.', 'Chronic fetal hypoxia and IUGR were experimentally induced by single umbilical artery ligation (SUAL) in catheterised fetal sheep. Maternal and fetal blood samples and amniotic fluid (AF) samples were collected during surgery and thereafter on alternate days, until the time of delivery for analyte measurement. Fetal blood gas parameters were measured daily.', 'Plasma and AF was used to analyse activin A, prostaglandin E2 (PGE2) and cortisol and fetal blood gas analysis was undertaken in whole blood.', 'SUAL produced asymmetric IUGR and non-acidaemic chronic fetal hypoxia and resulted in preterm labour (129 [3] days). AF activin A concentrations were 10-fold higher in the SUAL group than in controls whereas levels in the fetal and maternal circulations were similar between groups.

A: Does chronic fetal hypoxia increase activin A concentrations in the late-pregnant sheep?
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Q: To investigate the role of nitric oxide (NO)-induced autophagy in human dental pulp cells (HDPCs) and the involvement of AMP-activated protein kinase (AMPK) pathway.', "The MTT assay was used to determine the cytotoxic effect of the NO donor sodium nitroprusside (SNP) in HDPCs. Apoptosis was detected by means of the terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, and apoptosis- or autophagy-related signal molecules were observed by Western blot analysis. Acidic autophagolysosomal vacuoles were stained with acridine orange to detect autophagy in the presence of 3-methyladenine (3MA) used to inhibit autophagy. To explore the mechanism underlying autophagy and its protective role against apoptosis, compound C, the chemical AMPK inhibitor, was used. Statistical analysis was performed using Student's t-test or analysis of variance (ANOVA) followed by the Student-Newman-Keuls test (p<0.05).", 'SNP decreased viability of the HDPCs in a dose- and time-dependent manner. Exposing the HDPCs to SNP increased the levels of p62 and LC3-II, the typical markers of autophagy, and increased the number of acidic autophagolysosomal vacuoles, indicating the appearance of autophagy as detected by acridine orange staining (p<0.05). Pretreatment with 3MA decreased cell viability but increased cleaved poly (ADP-ribose) polymerase (PARP) and caspase-3, apoptosis indicators, in the SNP-treated HDPCs (p<0.05). SNP activated AMPK/ULK signaling, while the inhibition of AMPK by compound C enhanced apoptotic cell death induced by SNP in the HDPCs (p<0.05).

A: Do nitric oxide-induced autophagy and the activation of AMPK pathway protect against apoptosis in human dental pulp cells?
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Q: Recent research has revealed that classically trained tenors tend to constrict epilaryngeal structures when singing in and above the passaggio (ie, the frequency region where register events typically occur). These constrictions complicate visibility of vocal fold oscillatory patterns with transoral rigid high-speed video endoscopy, thus limiting the current understanding of laryngeal dynamics in the passaggio region of tenors.', 'This investigation analyzed seven professionally trained western classical tenors using high-speed digital imaging (HSDI) at 20,000 frames per second via transnasal flexible endoscopy. The participants produced transitions (a) from modal to falsetto register and (b) from modal to stage voice above the passaggio (SVaP) during ascending pitch glides from A3 (220\u2009Hz) to A4 (440\u2009Hz) on vowel /i/. HSDI data were complemented by simultaneous acoustic and electroglottographic recordings.', 'For many subjects both transition types were associated with constrictions of the epilaryngeal structures during the pitch glide. These constrictions appeared to be more distinct for the SVaP than for falsetto. No major irregularities of vocal fold oscillations in the sense of fundamental frequency jumps were observed for either transition type. However, during the transitions, the open quotient derived from the glottal area waveform (OQ

A:
Does oscillatory Characteristics of the Vocal fold Across the Tenor Passaggio?
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