TASK DEFINITION: In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
PROBLEM: Context: Reduction-oxidation (redox) signaling, the translation of an oxidative intracellular environment into a cellular response, is mediated by the reversible oxidation of specific cysteine thiols. The latter can result in disulfide formation between protein hetero- or homodimers that alter protein function until the local cellular redox environment has returned to the basal state. We have previously shown that this mechanism promotes the nuclear localization and activity of the Forkhead Box O4 (FOXO4) transcription factor.', 'In this study, we sought to investigate whether redox signaling differentially controls the human FOXO3 and FOXO4 paralogs.', 'We present evidence that FOXO3 and FOXO4 have acquired paralog-specific cysteines throughout vertebrate evolution. Using a proteome-wide screen, we identified previously unknown redox-dependent FOXO3 interaction partners. The nuclear import receptors Importin-7 (IPO7) and Importin-8 (IPO8) form a disulfide-dependent heterodimer with FOXO3, which is required for its reactive oxygen species-induced nuclear translocation. FOXO4 does not interact with IPO7 or IPO8.\Question: Does evolutionary acquisition of cysteines determine FOXO paralog-specific redox signaling?

SOLUTION: IPO7 and IPO8 control the nuclear import of FOXO3, but not FOXO4, in a redox-sensitive and disulfide-dependent manner. Our findings suggest that evolutionary acquisition of cysteines has contributed to regulatory divergence of FOXO paralogs, and that phylogenetic analysis can aid in the identification of cysteines involved in redox signaling.

PROBLEM: Context: Our previous work demonstrated altered messenger RNA expression of integrin -5 and -8, using an in silico analysis of publically available data from patients with biliary atresia (BA); however, we were unable to demonstrate statistically significant differences in protein expression because of sample size. In the present study, we repeated the analysis of liver fibrosis and protein expression of the integrins in a larger cohort of patients with BA and compared them with patients undergoing liver biopsy for other diagnoses, with the hypothesis that 1 of the integrins would be differentially expressed.', 'Liver specimens were obtained at 2 collaborating institutions. Samples from infants with BA (n = 23) were compared with samples from those who underwent liver biopsy for neonatal hepatitis (n = 9). All of the specimens were analyzed by 2 pathologists (C.R. and R.A.), who were blinded to the diagnoses. Standard Ishak scoring was performed to evaluate fibrosis and inflammation, and immunohistochemical (IHC) positivity was graded from 0 to 4. Comparisons between the IHC positivity and Ishak scoring for the BA and control groups were performed using the Student t test with P < 0.01 considered significant because of the multiple comparisons. Interobserver variability was assessed by intraclass correlation (ICC).', 'Pooled analysis from specimens from patients with BA showed significantly more fibrosis than controls based on Ishak scores (3.21 1.82 vs 1.17 1.00, P < 0.005). IHC evaluation showed increased integrin 8 protein expression when compared with controls (2.67 0.81 vs 1.72 0.62, P < 0.005); however, there were no significant differences in integrin 5 (1.93 0.84 vs 1.50 0.90, P = 0.23) or integrin 6 (0.85 1.20 vs 0.94 0.85, P = 0.82) expression. These data were confirmed on individual analysis. Interobserver agreement was fair for integrin 5 (ICC 0.52), good for integrin 6 (ICC 0.72), and excellent for integrin 8 (ICC 0.79) and fibrosis (ICC 0.89).\Question: Is integrin -8 , but not -5 or -6 , protein expression increased in livers of children with biliary atresia?

SOLUTION: Our data show that integrin 8, but not integrin 5 or integrin 6, protein expression is increased in liver specimens of patients with BA. These data support the mounting evidence that transforming growth factor- (TGF-) activation is responsible for the fibrosis found in BA. Anti-integrin 8 or more global integrin blocking strategies may be therapeutic options in BA, but further work is clearly needed.

PROBLEM: Context: Severe malaria (SM) is classically associated with Plasmodium falciparum infection. Little information is available on the contribution of P. vivax to severe disease. There are some epidemiological indications that P. vivax or mixed infections protect against complications and deaths. A large morbidity surveillance conducted in an area where the four species coexist allowed us to estimate rates of SM among patients infected with one or several species.', 'This was a prospective cohort study conducted within the framework of the Malaria Vaccine Epidemiology and Evaluation Project. All presumptive malaria cases presenting at two rural health facilities over an 8-y period were investigated with history taking, clinical examination, and laboratory assessment. Case definition of SM was based on the World Health Organization (WHO) criteria adapted for the setting (i.e., clinical diagnosis of malaria associated with asexual blood stage parasitaemia and recent history of fits, or coma, or respiratory distress, or anaemia [haemoglobin < 5 g/dl]). Out of 17,201 presumptive malaria cases, 9,537 (55%) had a confirmed Plasmodium parasitaemia. Among those, 6.2% (95% confidence interval [CI] 5.7%-6.8%) fulfilled the case definition of SM, most of them in children <5 y. In this age group, the proportion of SM was 11.7% (10.4%-13.2%) for P. falciparum, 8.8% (7.1%-10.7%) for P. vivax, and 17.3% (11.7%-24.2%) for mixed P. falciparum and P. vivax infections. P. vivax SM presented more often with respiratory distress than did P. falciparum (60% versus 41%, p = 0.002), but less often with anaemia (19% versus 41%, p = 0.0001).\Question: Are plasmodium vivax and mixed infections associated with severe malaria in children : a prospective cohort study from Papua New Guinea?

SOLUTION:
P. vivax monoinfections as well as mixed Plasmodium infections are associated with SM. There is no indication that mixed infections protected against SM. Interventions targeted toward P. falciparum only might be insufficient to eliminate the overall malaria burden, and especially severe disease, in areas where P. falciparum and P. vivax coexist.