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Abstract Background Long‐term survival can be achieved with radical local therapy in some cases of postoperative recurrence of non‐small cell lung cancer (NSCLC). Here, we evaluated post‐recurrence survival (PRS) after treatment of postoperative recurrent epidermal growth factor receptor (EGFR) mutated NSCLC and examined the effectiveness of radical local therapy. Methods This multicenter prospective cohort study was conducted in 14 hospitals. The inclusion criteria for this study were patients with recurrence after radical resection for NSCLC. Information about the patient characteristics at recurrence, tumor‐related variables, primary surgery, and treatment for recurrence was collected. After registration, follow‐up data (e.g., treatment and survival outcomes) were obtained and analyzed. Results From 2010 to 2015, 505 patients with recurrent NSCLC were enrolled into the study, and 154 EGFR mutation‐positive cases were included. As the initial treatment for recurrence, 111 patients (72%) received chemotherapy, 14 (9%) received chemoradiotherapy, 14 (9%) received definitive radiotherapy, and seven (5%) received surgical resection. The remaining eight patients (5%) received supportive care. The median PRS and 5‐year survival rates for all cases were 64 months and 53.2%, respectively. The 5‐year survival rate according to the initial treatment was as follows: supportive care, 0%; chemotherapy, 53.3% and radical local therapy, 60.1%. The six patients who received radical local treatment remained recurrence‐free for more than 3 years after recurrence with only initial treatment. Conclusions Although radical local therapy may be curative in some patients, chemotherapy including EGFR‐TKI treatment is expected to provide long‐term survival comparable to that of radical local therapy.

We analyzed low molecular weight organic acids and aldehydes in throughfall under pine forest, and organic acids in dew on chemically inert surfaces and pine needle surfaces at urban- and mountain-facing sites of pine forest in western Japan. Low molecular weight organic acids and aldehydes accounted for less than 5% of the dissolved organic carbon in throughfall at both sites. Formaldehyde at both sites and formate at the mountain-facing site were found at significantly lower concentrations in throughfall than in rainfall, which may be explained by the degradation and/or retention of these components by the pine canopy as the incident precipitation passed through it. The oxalate concentration in throughfall was significantly higher than those in rainfall at both sites, suggesting that oxalate was derived from leaching from the pine foliage. At both sites, organic acid concentrations were higher in dew on the pine needles than in throughfall or dew on chemically inert surfaces. This could be due to the long contact time of dew on pine needles, during which leached substances from pine needles and dry deposits accumulated on their surfaces can dissolve into the small volume of dew. The role of enhanced concentrations of oxalate in an aqueous phase on the plant surfaces (e.g., dew) is discussed in relation to hydroxyl radical formation via the photo-Fenton reaction.

The effects of various fractions of copper (Cu) and zinc (Zn) on soil bacteria were evaluated by the heavy metal tolerance level of the bacterial community (IC50) in soil samples collected near a mine. The IC50 values had no relationship with the total concentrations of Zn and Cu in the soils, but were weakly correlated with the 0.05 M CaCl2-extractable form of each metal in the soils (Cu: R2 = 0.670, p < 0.01; Zn: R2 = 0.453, p < 0.05). It was found that the IC50 correlated strongly with the total concentration of each metal in the extracts from water-saturated soil samples, described below as "soil solution" (Cu: R2 = 0.789, p < 0.01; Zn: R2 = 0.617, p < 0.01). The speciation of these metals in the soil solutions was estimated using an equilibrium thermodynamic computer model, SOILCHEM. Simulated free Cu ion ranged from 18 to 98% of total Cu, and organic complexes of Cu ranged from < 1 to 56%. In all samples, Zn existing as the free ion was estimated to be more than 80% of total Zn in the soil solutions. The IC50 values were also correlated with the estimated free metal ion activities, but with slightly lower correlation coefficients than found for total concentration in the soil solutions (Cu: R2 = 0.735, p < 0.01; Zn: R2 = 0.610, p < 0.01). The results suggest that not only high metal ion activities, but also total dissolved metal concentrations in soil solutions may affect the bacterial community.