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: Cyclosporine causes intrarenal vasoconstriction, which may account for its nephrotoxic side effects. Plasma levels of the vasoconstrictor peptide endothelin-1 are increased after cyclosporine administration, and endothelin-1 has been shown to cause renal vasoconstriction. In this study we used in vivo microscopy to investigate the role of endothelin-1 in cyclosporine-induced vasoconstriction.', 'Hydronephrotic kidneys in decerebrate rats were suspended in an environmentally controlled tissue bath with neurovascular supply intact. Interlobular, afferent, and efferent arteriolar diameters and flow were measured by videomicroscopy and Doppler velocimetry. Cyclosporine was added to the tissue bath, and measurements were repeated for 60 minutes. In study groups endogenous endothelin-1 was blocked by infusion of either specific endothelin antiserum or an endothelin-1 receptor antagonist.', 'Cyclosporine caused constriction of the interlobular artery by 20% +/- 2% and a corresponding decrease in blood flow by 66% +/- 4%. The afferent and efferent arterioles constricted to a similar degree. This vasoconstriction was entirely prevented by infusion of either the endothelin antiserum or the receptor antagonist. The antagonist reagents alone had no effect on hemodynamic parameters or renal microvessel diameters.
Answer: The acute renal vasoconstriction induced by cyclosporine is mediated by endothelin-1. Endogenous endothelin-1 has little role in maintaining basal vascular tone.
answer:
Is acute cyclosporine-induced renal vasoconstriction mediated by endothelin-1?


question:
Context: Obstetric cholestasis is a cholestatic disease usually commencing in the third trimester of pregnancy and characterized by pruritus, elevation of liver enzymes, and increase in bile acids. The objective of this study was to compare the first trimester serum indicators of obstetric cholestasis with normal pregnancies.', 'Thirty-five patients diagnosed with obstetric cholestasis in a three-year period with first trimester biochemical assessment available were included in the study. Seventy patients with concordant pregnancy weeks, matched-age normal pregnancies were included as the control group. Pregnancy-associated plasma protein A (PAPP-A) and free beta-human chorionic gonadotropin (beta-hCG) levels were analyzed.', 'No difference was observed between the two groups in terms of age and week of pregnancy. While the mean PAPP-A level was 0.76 ± 0.31 multiples of the medians (MoM) in the obstetric cholestasis group, it was determined to be 1.5 ± 0.84 in the control group (p = 0.0001). Among the two groups, the hCG levels were found to be higher in the obstetric cholestasis group (1.2 ± 0.79 MoM vs. 0.98 ± 0.53, p = 0.041).
Answer: In this study, the first trimester PAPP-A levels in the obstetric cholestasis cases were found to be significantly lower than the control group. Low PAPP-A levels should be a warning for obstetric cholestasis.
answer:
Are pregnancy-associated plasma protein a levels decreased in obstetric cholestasis?


question:
Context: Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females.', 'To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners.', 'Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05).', 'Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (p<0.05). Flexible females (36.7±7.4º) exhibited more hip flexion than inflexible females (27.9±4.6º, p<0.01) and flexible males (30.1±9.5º, p<0.05). No differences existed for knee angle at initial contact, peak knee angle, peak hip angle, or peak hip moment.
Answer: Hamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners.
answer:

Do male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility?