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.

[Q]: Context: To study the effect of Cleistocalyx nervosum extract (CE) on diethylnitrosamine (DEN) and phenobarbital (PB) induced oxidative stress in early stages of rat hepatocarcinogenesis.', 'Male Wistar rats were divided into 4 groups, with Group 1 as a negative control and Group 2 was a positive control receiving DEN injections once a week and PB in drinking water for 6 weeks. Two weeks before DEN initiation and PB treatment, Groups 3 and 4, were fed with 500 and 1000 mg/kg of CEs, respectively, for 8 weeks.', 'A number of GST-P-positive foci, preneoplastic lesions, in the liver were markedly increased in carcinogen administered rats, but was comparatively decreased in rats treated with 1000 mg/kg of CE. The CE reduced malondialdehyde in serum and in the livers of rats treated with DEN and PB. Moreover, CE significantly increased the activities of glutathione peroxidase and catalase in rat liver.
Answer: CE appeared to exert its chemopreventive effects by modulating antioxidant status during DEN and PB induced early stages of hepatocarcinogenesis in rats.
[A]: Does cleistocalyx nervosum extract ameliorate chemical-induced oxidative stress in early stages of rat hepatocarcinogenesis?

[Q]: Context: Recently, the Arg389Gly beta1-adrenoceptor (beta1AR) gene polymorphism has been detected. The Arg variant exhibited increased responsiveness to agonist-induced stimulation in vitro. Functional studies in isolated human atrial muscle strips and in-vivo studies revealed contradictory results regarding the functional relevance of this polymorphism. We sought to characterize the functional consequences of the Arg389Gly beta1-AR polymorphism in 30 consecutive healthy male volunteers in vivo.', 'beta1-AR genotype was determined by PCR and restriction analysis, which was confirmed by DNA sequencing. We compared heart rate, blood pressure, and contractile response of the various genotype carriers with a modified dobutamine stress echocardiography protocol.', 'Subjects homozygous for the Arg389 beta1AR showed a significantly higher increase in fractional shortening upon cumulative doses of dobutamine as compared to subjects carrying one or two copies of the Gly389 allele. A statistically significant difference was observed at a dobutamine dose of 10 microg/kg/min (46.5 +/- 1.3 vs. 41.8 +/- 1.0 %; P = 0.023) and was maximal at 40 microg/kg/min (61.9 +/- 1.4 vs. 52.8 +/- 1.6; P = 0.001). As a result, the systolic blood pressure response to dobutamine was significantly enhanced in individuals homozygous for the Arg389 allele, whereas the effect on heart rate did not differ between the two groups. Normalization for changing afterload conditions by calculating the pressure-dimension ratio revealed similar effects, indicating that the beta1AR-mediated effects are mainly a result of increased myocardial inotropy.
Answer: These data indicate that the Arg389Gly beta1AR polymorphism is functionally relevant in vivo and determines contractile responsiveness to catecholamines in humans.
[A]: Does the Arg389Gly beta1-adrenoceptor gene polymorphism determine contractile response to catecholamines?

[Q]: Context: Partial DiGeorge syndrome (pDGS) is caused by deletion of the 22q11.2 region. Within this region lies CrK-like (CRKL), a gene encoding an adapter protein belonging to the Crk family that is involved in the signaling cascade of IL-2, stromal cell-derived factor 1, and type I interferon. Although recurrent infections can be observed in patients with deletion of chromosome 22 syndrome, the immune pathogenesis of this condition is yet not fully understood.', 'We aimed to investigate the role of CRKL in T-cell functional responses in patients affected with pDGS.', 'Protein expression levels and phosphorylation of CRKL were evaluated in patients with pDGS. T-cell functional assays invitro and gene-silencing experiments were also performed.', 'CRKL protein expression, as well as its phosphorylation, were reduced in all patients with pDGS, especially on IL-2 stimulation. Moreover, Tcells presented impaired proliferation and reduced IL-2 production on anti-CD3/CD28 stimulation and decreased c-Fos expression. Finally, CRKL silencing in Jurkat Tcells resulted in impaired T-cell proliferation and reduced c-Fos expression.
Answer: The impaired T-cell proliferation and reduction of CRKL, phosphorylated CRKL, and c-Fos levels suggest a possible role of CRKL in functional deficiencies of Tcells in patients with pDGS.
[A]:
Is reduction of CRKL expression in patients with partial DiGeorge syndrome associated with impairment of T-cell functions?