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: Critical size defects (CSDs) of bone are defined as defects that do not heal spontaneously to new bone during the lifetime of an adult individual. In contrast, immature animals are capable to heal defects of identical size. It was our hypothesis that age-related paracrine effects are relevant for this difference in regeneration.', 'The pooled supernatant of primary rat calvarial osteoblast-like cell cultures (POBC) derived from prenatal or postnatal donors was concentrated and applied into CSDs of adult recipient organisms (n = 10). In addition, the supernatant of POBC derived from prenatal donors was pooled and purified by reverse-phase chromatography. Each pre-purified fraction was tested in a proliferation indicating bioassay. Peptide fractions containing proliferative activities were re-chromatographed and re-tested in a bioassay. Finally, a proliferative activity was purified, identified by sequence analysis and applied into CSDs of adult recipients.', 'The application of POBC derived from prenatal donors resulted in osseous regeneration of a CSD in adult recipients, while the supernatant of postnatal donors had much smaller effects. The morphologic features resembled the spontaneous osseous healing of calvarial defects of the same size in immature organisms. The polypeptide "tissue inhibitor of metalloproteinases type II"(TIMP-2) was isolated from the supernatant of cultures of POBC derived from prenatal donors by measuring the induction of their proliferation. Additionally, the application of human TIMP-2 injected into calvarial CSDs of adult organisms resulted in osseous healing.
Answer: We conclude that one component responsible for the healing effect of CSDs of POBC supernatants derived from prenatal donors is TIMP-2.
[A]: Is tissue inhibitor of metalloproteinases II ( TIMP-2 ) an osteoanabolic factor in vitro and in vivo?

[Q]: Context: To develop a method for quick identification of sun-dried and sulfur-fumigated Cimicifugae Rhizoma by Fourier transform infrared spectroscopy (FTIR).', 'The alcoholic and aqueous extracts of sun-dried and sulfur-fumigated Cimicifugae Rhizoma were analyzed and compared by FTIR combined with second derivative infrared spectroscopy.', 'FTIR spectra showed that there were some differences in the positions of infrared absorption peaks and the relative intensities in the alcoholic and aqueous extracts of sun-dried and sulfur-fumigated Cimicifugae Rhizoma, and the second derivative IR spectra clearly enhanced the spectral resolution of their differences. FTIR spectra showed that the new absorption peaks of Cimicifugae Rhizoma appeared and a part of original absorption peaks disappeared after sulfur-fumigation in aqueous extracts, while a lot of new absorption peaks appeared and the intensities of almost all absorption peaks significantly decreased after sulfur-fumigation in alcoholic extracts. Second derivative IR spectra showed that both sun-dried and sulfur-fumigated Cimicifugae Rhizoma extracted by water differed significantly from each other ranging from about 3 950 to 3 940 cm(-1), 3 850 to 3 800 cm(-1), 1 800 to 1 750 cm(-1), as well as from 1 400 to 1 350 cm(-1); Differences also existed between sun-dried and sulfur-fumigated Cimicifugae Rhizoma extracted by ethanol ranging from about 3 980 to 3 960 cm(-1), 3 850 to 3 800 cm(-1), and 1 500 to 1 460 cm(-1).
Answer: The FTIR method combined with the second derivative IR spectrum can be used to analyze and distinguish sun-dried and sulfur-fumigated Cimicifugae Rhizoma quickly and accurately. The developed method provides an efficient approach for the quality control of Chinese herbal medicines with its simplicity and strong specificity.
[A]: Do [ Quick identification and discrimination of sun-dried and sulfur-fumigated cimicifugae rhizoma by Fourier transform infrared spectroscopy ]?

[Q]: Context: Although trastuzumab improves the outcome of patients with human epidermal growth factor receptor2 (HER2)-overexpressing gastric or gastroesophageal junction adenocarcinoma (collectively referred to as "gastroesophageal adenocarcinoma"; GEA), no clinical response is observed in a substantial population of patients. A predictive biomarker of trastuzumab response is required. The aim of this study was to evaluate whether the hyperactivation of the downstream phosphatidylinositol 3-kinase pathway, due to phosphatase and tensin homolog (PTEN) loss or PIK3CA mutations, could provide trastuzumab resistance in GEA.', 'Expression of HER2 and PTEN, and PIK3CA gene mutations were screened in 264 surgically resected GEA specimens. The effects of PTEN knockdown on the response to trastuzumab on cell viability, HER2 downstream signaling, apoptosis, and cell cycle were evaluated in HER2-overexpressing NCI-N87 gastric adenocarcinoma and OE19 esophageal adenocarcinoma cell lines. Inhibition of xenograft tumor growth by trastuzumab was investigated in OE19 cells with or without PTEN knockdown. The PTEN expression and objective response were analyzed in 23 GEA patients who received trastuzumab-based therapy.', 'PTEN loss was identified in 34.5% of HER2-overexpressing GEA patients, whereas PIK3CA mutations were rare (5.6%). Trastuzumab-mediated growth suppression, apoptosis, and G
Answer: PTEN loss was frequently found in HER2-overexpressing tumors, and was associated with a poor response to trastuzumab-based therapy in patients with GEA.
[A]:
Is pTEN loss associated with a poor response to trastuzumab in HER2-overexpressing gastroesophageal adenocarcinoma?