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]: Tubuloglomerular feedback (TGF) is an important mechanism in control of signal nephron glomerular filtration rate. The oxidative stress in the macula densa, primarily determined by the interactions between nitric oxide (NO) and superoxide (O2-), is essential in maintaining the TGF responsiveness. However, few studies examining the interactions between and amount of NO and O2- generated by the macula densa during normal and hypertensive states.', 'In this study, we used isolated perfused juxtaglomerular apparatus to directly measure the amount and also studied the interactions between NO and O2- in macula densa in both physiological and slow pressor Angiotensin II (Ang II)-induced hypertensive mice.', 'We found that slow pressor Ang II at a dose of 600ng kg(-1) min(-1) for two weeks increased mean arterial pressure by 26.1 5.7mmHg. TGF response increased from 3.40.2m in control to 5.20.2m in hypertensive mice. We first measured O2- generation by the macula densa and found it was undetectable in control mice. However, O2- generation by the macula densa increased to 21.42.5 unit min(-1) in Ang II-induced hypertensive mice. We then measured NO generation and found that NO generation by the macula densa was 138.59.3 unit min(-1) in control mice. The NO was undetectable in the macula densa in hypertensive mice infused with Ang II.
[A]: Does oxidative status in the macula densa modulate tubuloglomerular feedback responsiveness in angiotensin II-induced hypertension?

[Q]: Cervical carcinoma is the second most common malignancy in females and most of the cases are found in developing countries. The objectives of the present study were (a): to demonstrate the antiproliferative and apoptotic effects of Achillea falcata (A.falcata) extract in human cervical cancer cells (HeLa), and (b): to study the effect of the extract on cellular morphology, cell cycle phase distribution and mitochondrial membrane potential.', 'MTT assay was used to evaluate the anticancer effect of the extract on HeLa cells. Phase contrast, fluorescence microscopy and transmission electron microscopy (TEM) were used to investigate the morphological changes in these cancer cells after extract treatment. Flow cytometry was used to evaluate the effects of the extract on cell cycle and mitochondrial membrane potential.', 'The results revealed that A. falcata extract led to a significant antiproliferative effect in HeLa cancer cells. The extract induced cellular shrinkage, chromatin condensation and appearance of apoptotic bodies which are the hallmarks of cellular apoptosis. TEM results showed that extract-treated cells had nuclear membrane which was hemispherical and the nuclear chromatin was concentrated and bundled on the inner border of karyotheca. The endoplasmic reticulum also became enlarged in the inner segment. The extract also induced G2/M phase cell cycle arrest along with loss of mitochondrial membrane potential.
[A]: Are antiproliferative and apoptotic effects of the ethanolic herbal extract of Achillea falcata in human cervical cancer cells mediated via cell cycle arrest and mitochondrial membrane potential loss?

[Q]: Obstructive sleep apnea (OSA) has been linked with erectile dysfunction (ED), but it is unknown whether this association is maintained in the presence of other risk factors for ED.', 'The aim of this study was to evaluate the relationship between ED/sexual dysfunction and polysomnographic measures of sleep apnea in patients with known risk factors for ED.', 'Prospective cross-sectional analysis of 401 male patients undergoing in-lab polysomnography for suspected OSA. Erectile (EF) and sexual function were assessed by the 15-item International Index of Erectile Function (IIEF-15) questionnaire.', 'Severity of OSA via apnea-hypopnea index (AHI) and mean/lowest nocturnal oxygen saturation (SaO(2)). The IIEF-15 including the sexual domains: EF, intercourse satisfaction, orgasmic function, sexual desire, and overall satisfaction.', 'OSA (AHI > 5/h) was diagnosed in 92% of patients. ED (EF subdomain < or = 25) was present in 69% of patients with, and 34% of patients without OSA (P < 0.001). Multivariate stepwise regression analyses including known risk factors for ED, such as age, obesity, coronary heart disease, peripheral occlusive disease, hypertension, diabetes, prostate surgery, and beta-blocker treatment, and measures of sleep apnea identified mean nocturnal SaO(2) as independently associated with ED (P = 0.002; mean [95% CI] normalized slope 0.126 [0.047; 0.205]). Age (P < 0.001), peripheral occlusive disease (P = 0.001), prostate surgery (P = 0.018), and hypertension (P = 0.021) were confirmed as risk factors for ED, but did not abolish the sleep apnea-associated risk. Similar results were obtained for sexual dysfunction. Logistic regression analysis using the diagnosis of ED (EF subdomain < or = 25) as binary dependent variable confirmed that mean nocturnal SaO(2) (P = 0.012), as well as age (P < 0.001) were independently associated with ED.
[A]:
Is sleep apnea an independent correlate of erectile and sexual dysfunction?