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.

Example Input: Context: Somatic cells in vitro have a finite life expectancy before entering a state of senescence, but it is unclear whether this state occurs in vivo in kidney development, growth, and aging. We previously showed that human kidney cortex displays telomere shortening with age. In this study, we compared the structural and functional changes in rat kidney with age to phenomena associated with cellular senescence in vitro.', 'We assessed the changes in Fischer 344 rat kidneys from age 1 to 9 months to define growth and development and from age 9 to 24 months to define aging.', 'Rat kidney telomeres were approximately 35 to 40 kb long and did not shorten significantly. Expression of mRNA for p16INK4a, a characteristic senescence gene in vitro, was undetectable in most young rats but rose 27 fold during growth and a further 72-fold during aging. p16INK4a protein was localized to the nucleus and increased with age. p16INK4a mRNA also increased in other tissues. Lipofuscin and senescence-associated beta-galactosidase increased in epithelium with growth and aging and their occurrence was significantly associated with each other. Lipofuscin was particularly found in atrophic nephrons.\Question: Does cell senescence in rat kidneys in vivo increase with growth and age despite lack of telomere shortening?
Example Output: We conclude that cell senescence occurs in both growth and aging in rat kidney and may contribute to the age-related pathology. These changes are not due to telomere shortening, but may reflect cumulative environmental stress.

Example Input: Context: Strontium ranelate reduces fracture risk in postmenopausal women with osteoporosis. Evidence from non-clinical studies and analyses of bone markers in phase III trials indicate that this is due to an increase in osteoblast formation and a decrease of osteoclastic resorption. The aim of this work was to investigate, in human cells, the mechanisms by which strontium ranelate is able to influence the activities of osteoblasts and osteoclasts.', 'Human primary osteoblasts were used to examine effects of strontium ranelate on replication (thymidine incorporation), differentiation (Runx2 and alkaline phosphatase) and cell survival (cell counts and caspase activity). Osteoprotegerin (OPG) was measured by quantitative reverse transcription PCR (qRT-PCR) and elisa and receptor activator of NFkappaB ligand (RANKL) by qRT-PCR and Western blot. As strontium ranelate has been proposed as an agonist of the calcium-sensing receptor (CaSR), the involvement of CaSR in the effects of strontium ranelate on OPG and RANKL expression, and cell replication was examined using siRNA.', 'Strontium ranelate increased mRNA and protein levels of OPG and suppressed those of RANKL. Strontium ranelate also stimulated osteoblast replication and differentiation and increased cell survival under stress. Knocking down CaSR suppressed strontium ranelate-induced stimulation of OPG mRNA, reduction of RANKL mRNA, and increase in replication, indicating the involvement of CaSR in these responses.\Question: Do osteoblasts play key roles in the mechanisms of action of strontium ranelate?
Example Output: Our results demonstrate that osteoblasts play a key role in the mechanism of action of the anti-fracture agent, strontium ranelate by mediating both its anabolic and anti-resorptive actions, at least in part, via activation of CaSR.

Example Input: Context: The microbial etiology of periradicular lesions is recognized; however, the bacterial profile of these lesions is not well elucidated. The purpose of this study was to determine the frequency of bacterial colonization in these lesions and to characterize the bacterial community present in root ends and periradicular lesions.', 'Thirty-four adult patients who presented for apicoectomy of persistent periradicular lesions after endodontic therapy were selected for the study and samples of periradicular tissue and resected root ends collected. Total bacterial levels were estimated for 34 paired periradicular lesions and root ends using real-time polymerase chain reaction with universal bacterial primers. Sixteen pairs of these samples were analyzed using ribosomal 16S cloning and sequencing for bacterial identification.', 'Bacteria were detected more consistently and at higher levels in root ends. Periradicular lesions exhibited a diverse microbial profile with many uncultivated phylotypes. Enterococcus faecalis and Burkholderia cepacia predominated in both samples. Campylobacter gracilis and Streptococcus gordonii were associated with root ends, whereas Atopobium rimae, Peptostreptococcus micros, Streptococcus genomospecies C8, Dialister sp E2_20 E1, and Eubacterium strain A35MT were associated with periradicular lesions.\Question: Does molecular analysis of persistent periradicular lesions and root end reveals a diverse microbial profile?
Example Output:
Persistent periradicular lesions are polymicrobial infections with many as-yet-uncultivated and unknown bacterial species. The bacterial load and microbial profile of root ends is significantly different from the soft-tissue lesion, indicating the presence of diverse bacterial populations in these tissues.