TASK DEFINITION: In this task, you are given an abstract of article. Your task is to generate label "True" if abstract is structured, otherwise generate "False". A structured abstract is composed of a topic sentence (or key sentence), relevant supporting sentences, and a closing (or transition) sentence. This structure is key to keeping your abstract focused on the main idea and creating a clear and concise image.
PROBLEM: There is a growing interest in the cell-cell communication roles in cancer mediated by secreted vesicles termed exosomes. In this study, we examined whether exosomes produced by cancer cells could transmit information to normal stromal fibroblasts and trigger a cellular response. We found that some cancer-derived exosomes could trigger elevated -smooth muscle actin expression and other changes consistent with the process of fibroblast differentiation into myofibroblasts. We show that TGF- is expressed at the exosome surface in association with the transmembrane proteoglycan betaglycan. Although existing in a latent state, this complex was fully functional in eliciting SMAD-dependent signaling. Inhibiting either signaling or betaglycan expression attenuated differentiation. While the kinetics and overall magnitude of the response were similar to that achieved with soluble TGF-, we identified important qualitative differences unique to the exosomal route of TGF- delivery, as exemplified by a significant elevation in fibroblast FGF2 production. This hitherto unknown trigger for instigating cellular differentiation in a distinctive manner has major implications for mechanisms underlying cancer-recruited stroma, fibrotic diseases, and wound-healing responses.

SOLUTION: False

PROBLEM: This study examines factors associated with caregiver burden in 82 HIV-positive (HIV+) and 162 HIV-negative (HIV-) partners of men with AIDS. We expected HIV+ caregivers to report more burden than HIV- caregivers because of the toll of their disease on their resources. HIV+ caregivers did report more burden and, compared with the HIV- caregivers, they were more religious or spiritual, had less income, and coped by using more positive reappraisal and cognitive escape-avoidance and by seeking social support. Comparisons of HIV+ caregivers with 61 HIV+ partners of healthy men indicated that most differences between HIV+ and HIV- caregivers were associated with HIV seropositivity rather than caregiving. However, of the variables associated with HIV seropositivity, only religiosity or spirituality contributed independently to burden in HIV+ caregivers, suggesting a relatively weak link between HIV seropositivity and caregiver burden. The model explained 62% of the variance in burden in HIV+ caregivers and 36% of the variance in HIV- caregivers.

SOLUTION: False

PROBLEM: OBJECTIVE To investigate the antimicrobial property of mangrove plant Sonneratia alba (S. alba).
METHODS The antimicrobial activity was evaluated using disc diffusion and microdilution methods against six microorganisms. Soxhlet apparatus was used for extraction with a series of solvents, n-hexane, ethyl acetate and methanol in sequence of increasing polarity.
RESULTS Methanol extract appeared to be the most effective extract while n-hexane extract showed no activity. The antimicrobial activities were observed against the gram positive bacteria Staphylococcus aureus (S. aureus) and Bacillus cereus (B. cereus), the gram negative Escherichia coli (E. coli) and the yeast Cryptococcus neoformans. Pseudomonas aeruginosa and Candida albicans appeared to be not sensitive to the concentrations tested since no inhibition zone was observed. E. coli (17.5 mm) appeared to be the most sensitive strain followed by S. aureus (12.5 mm) and B. cereus (12.5 mm).
CONCLUSIONS From this study, it can be concluded that S. alba exhibits antimicrobial activities against certain microorganisms.

SOLUTION:
True