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: Bronchopulmonary carcinoid tumors can be divided into typical and atypical carcinoids according to their histologic and clinical features. Atypical carcinoids tend to have less predictable biologic behavior and are associated with a worse prognosis than typical carcinoids. The authors examined apoptosis and the expression of apoptosis regulating proteins Bcl-2, Bax, Bak, and Mcl-1 in 21 typical and 10 atypical bronchopulmonary carcinoid tumors. To find features distinguishing the growth of these types of tumors, the expression of p53 protein and the proliferation marker Ki-67 were also investigated. Finally, the parameters were compared with clinical follow-up data.', "Thirty-one bronchopulmonary carcinoid tumors were examined by using in situ 3'-end labeling of DNA (TUNEL) for apoptosis and immunohistochemical staining methods for Bcl-2, Bax, Bak, Mcl-1, p53, and Ki-67 in formalin fixed, paraffin embedded tissue specimens.", 'The apoptotic indices (AIs) were low in general (mean 0.18%), but higher AIs (> 0.5%) were observed significantly more often in atypical than in typical carcinoids (P < 0.008) in association with shortened survival (P < 0. 008). No relation between apoptosis and Bcl-2, Bax, Bak, or Mcl-1 expression was found. Expression of p53 protein was detected in only three atypical carcinoids, which also had significantly higher AIs than p53 negative tumors (P < 0.03). Proliferation rates measured by Ki-67 index were unusually low; the highest proliferation rates were observed in atypical carcinoids. There was a positive correlation between AI and Ki-67 indices (P < 0.01).\Question: Do atypical bronchopulmonary carcinoids show a tendency toward increased apoptotic and proliferative activity?

SOLUTION: This study suggests that the extent of apoptosis in bronchopulmonary carcinoid tumors is low. This, together with a low proliferation rate and an apparent absence of p53 mutation, enables a benign growth pattern. Some atypical carcinoids with enhanced apoptosis are associated with shortened survival, clearly deviating from typical carcinoids.

PROBLEM: Context: Cystic ovarian disease is an important cause of infertility that affects bovine, ovine, caprine and porcine species and even human beings. Alterations in the ovarian micro-environment of females with follicular cysts could alter the normal processes of proliferation and programmed cell death in ovarian cells. Thus, our objective was to evaluate apoptosis and proliferation in ovarian cystic follicles in rats in order to investigate the cause of cystic follicle formation and persistence.', 'We compared the number of in situ apoptotic cells by TUNEL assay, expression of active caspase-3 and members of Bcl-2 family by immunohistochemistry; and cell proliferation by the expression of the proliferation markers: PCNA and Ki-67.', 'The proliferation index was low in granulosa of tertiary and cystic follicles of light exposed rats when compared with tertiary follicles of control animals, while in theca interna only cystic follicles presented low proliferation index when compared with tertiary follicles (p < 0.05). The granulosa of cysts exhibited a similar cell DNA fragmentation to early atretic follicles. In the granulosa and theca interna, active caspase-3 shown similar immunostaining levels in tertiary and cystic follicles (p < 0.05). The granulosa cells presented high expression of Bcl-2, Bcl-xL and Bcl-w in the tertiary and cystic follicles with diminishing intensity in the atretic follicles, except with Bcl-w where the intensity was maintained in the atretic follicles (p < 0.05). The expression of Bax was weak in the healthy and cystic follicles. In the theca interna, Bcl-2 expression was the same as the pattern found in the granulosa; no differences were found between tertiary and cystic follicles from both groups for Bcl-xL and Bcl-w. The expression of Bax in this layer was higher in the tertiary follicles of the treated animals (p < 0.05) while the values for cystic follicles were similar to those in the tertiary follicles of controls. The theca externa showed low expression of the pro and anti-apoptotic proteins.\Question: Does an imbalance between apoptosis and proliferation contribute to follicular persistence in polycystic ovaries in rats?

SOLUTION: These results show that the combination of weak proliferation indices and low apoptosis observed in follicular cysts, could explain the cause of the slow growth of cystic follicles and the maintenance of a static condition without degeneration, which leads to their persistence. These alterations may be due to structural and functional modifications that take place in these cells and could be related to hormonal changes in animals with this condition.

PROBLEM: Context: Brassica napus (AACC) is self-compatible, although its ancestor species Brassica rapa (AA) and Brassica oleracea (CC) are self-incompatible. Most B.napus accessions have dominant self-compatibility (SC) resulting from an insertion of 3.6 kb in the promoter region of BnSCR-1 on the A genome, while recessive SC in B.napus has rarely been observed. Expression and cloning of SRK and SCR genes and genetic analysis were carried out to dissect bases of recessive SC in B.napus.', 'Eleven accessions were screened to identify stable recessive SC and had the S genotype BnS-7 on the A genome and BnS-6 on the C genome similarly to BrS-29 and BoS-15, respectively. In eight SC accessions, BnSCR-7 and BnSCR-6 were nearly undetectable and harbored no structural mutations in the promoters, while SRK genes were expressed at normal levels and contained intact CDS, with the exception of BnSRK-7 in line C32. SRK and SCR genes were expressed normally but their CDSs had no mutations in three SC accessions. In self-incompatible S-1300 and 11 F1 hybrids, SRK genes and BnSCR-1300 transcripts were present at high levels, while expression of the BnSCR-7 and BnSCR-6 were absent. Plants of S genotype S1300S1300 were completely SI, while SI phenotypes of SBnS-7SBnS-7 and S1300SBnS-7 plants were segregated in BC1 and F2 populations.\Question: Do gene expression and genetic analysis reveal diverse causes of recessive self-compatibility in Brassica napus L?

SOLUTION:
The recessive SC in eight accessions is caused by the loss of function of BnSCR-7 and BnSCR-6 in pollen. Translational repression contributes to the recessive SC in three accessions, whose SRK and SCR genes were expressed normally and had identical CDSs to BrS-29 or BoS-15. SI in 11 F1 hybrids relies on the expression of BnSCR-1300 rather than SRK genes. Other factor(s) independent of the S locus are involved in recessive SC. Therefore, diverse causes underlie recessive SC in B. napus, yielding insight into these complex mechanisms.