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.

Context: Bacteria often form multicellular, organized communities known as biofilms, which protect cells from a variety of environmental stresses. During biofilm formation, bacteria secrete a species-specific matrix; in Bacillus subtilis biofilms, the matrix consists of protein polymers and exopolysaccharide. Many domesticated strains of B. subtilis have a reduced ability to form biofilms, and we conducted a two-month evolution experiment to test whether laboratory culturing provides selective pressure against biofilm formation in B. subtilis.', 'Bacteria grown in two-month-long batch culture rapidly diversified their biofilm-forming characteristics, exhibiting highly diverse colony morphologies on LB plates in the initial ten days of culture. Generally, this diversity decreased over time; however, multiple types of colony morphology remained in our final two-month-old populations, both under shaking and static conditions. Notably, while our final populations featured cells that produce less biofilm matrix than did the ancestor, cells overproducing biofilm matrix were present as well. We took a candidate-gene approach to identify mutations in the strains that overproduced matrix and found point mutations in the biofilm-regulatory gene sinR. Introducing these mutations into the ancestral strain phenocopied or partially phenocopied the evolved biofilm phenotypes.
Answer: Our data suggest that standard laboratory culturing conditions do not rapidly select against biofilm formation. Although biofilm matrix production is often reduced in domesticated bacterial strains, we found that matrix production may still have a fitness benefit in the laboratory. We suggest that adaptive specialization of biofilm-forming species can occur through mutations that modulate biofilm formation as in B. subtilis.
Is sinR a mutational target for fine-tuning biofilm formation in laboratory-evolved strains of Bacillus subtilis?

Context: The modulation of intracortical inhibition is thought to be impaired in older adults, which may contribute to their reduced fine motor control, particularly during lengthening muscle contractions.', 'To quantify the magnitude of intracortical inhibition and movement performance during postural, shortening and lengthening contractions of a hand muscle in young and old adults.', 'In 18 young (23.2 4.2) and 16 old (70.6 6.5) subjects, paired-pulse transcranial magnetic stimulation (TMS) was used to assess short-interval intracortical inhibition (SICI) and long-interval intracortical inhibition (LICI) during a movement task involving the first dorsal interosseous muscle. The task required a constant load (50 g) to be slowly lifted and lowered using the index finger while single- or paired-pulse TMS was delivered during the shortening or lengthening contraction.', 'Relative to postural contractions, SICI during shortening contractions was reduced by 29% in young subjects (P < 0.0001) and 43% in old subjects (P < 0.0001), whereas SICI during lengthening contractions was reduced by 11% in young subjects (P = 0.0004) and 33% in old subjects (P < 0.0001). Furthermore, SICI was significantly less in older adults during lengthening contractions (P-values < 0.01). For LICI, inhibition was not influenced by contraction type in old subjects, but was increased by 11% during shortening contractions (P < 0.0001) and by 9% during lengthening contractions in young subjects (P = 0.0008). In addition, old subjects showed significantly less LICI than young subjects in each movement phase (both P-values < 0.05).
Answer: Shortening and lengthening contractions with a constant load are associated with a modulation of GABAergic inhibition that is altered by healthy ageing.
Is intracortical Inhibition Assessed with Paired-Pulse Transcranial Magnetic Stimulation Modulated during Shortening and Lengthening Contractions in Young and Old Adults?

Context: Despite recent advances in prostate cancer diagnostics and therapeutics, the overall survival rate still remains low. This study was aimed to assess potential anti-cancer activity of maysin, a major flavonoid of corn silk (CS, Zea mays L.), in androgen-independent human prostate cancer cells (PC-3).', 'Maysin was isolated from CS of Kwangpyeongok, a Korean hybrid corn, via methanol extraction and preparative C18 reverse phase column chromatography. Maysin cytotoxicity was determined by either monitoring cell viability in various cancer cell lines by MTT assay or morphological changes. Apoptotic cell death was assessed by annexin V-FITC/PI double staining, depolarization of mitochondrial membrane potential (MMP), expression levels of Bcl-2 and pro-caspase-3 and by terminal transferase mediated dUTP-fluorescein nick end labeling (TUNEL) staining. Underlying mechanism in maysin-induced apoptosis of PC-3 cells was explored by evaluating its effects on Akt and ERK pathway.', 'Maysin dose-dependently reduced the PC-3 cell viability, with an 87% reduction at 200 g/ml. Maysin treatment significantly induced apoptotic cell death, DNA fragmentation, depolarization of MMP, and reduction in Bcl-2 and pro-caspase-3 expression levels. Maysin also significantly attenuated phosphorylation of Akt and ERK. A combined treatment with maysin and other known anti-cancer agents, including 5-FU, etoposide, cisplatin, or camptothecin, synergistically enhanced PC-3 cell death.
Answer: These results suggested for the first time that maysin inhibits the PC-3 cancer cell growth via stimulation of mitochondria-dependent apoptotic cell death and may have a strong therapeutic potential for the treatment of either chemo-resistant or androgen-independent human prostate cancer.
Does corn silk maysin induce apoptotic cell death in PC-3 prostate cancer cells via mitochondria-dependent pathway?