Experimental study on the purification capacity of potted plants on low-concentration carbon monoxide in indoor environment.

Indoor low-concentration carbon monoxide (CO) exposure is widespread worldwide, and potted plants may be a potential means for CO purification. The objective is to evaluate common indoor plants' CO purification and tolerance capacities. Epipremnum aureum (Linden ex André) G.S.Bunting, Chlorophytum comosum (Thunb.) Jacques, Spathiphyllum kochii Engl. & K.Krause, and Sansevieria trifasciata Hort. ex Prain with similar sizes were tested in the glass chamber with initial CO concentrations of 10, 25, 50, 100, 200, and 400 ppm, respectively. (1) The CO purification capacity of the four potted plants is ranked as Epipremnum aureum (Linden ex André) G.S.Bunting > Chlorophytum comosum (Thunb.) Jacques > Spathiphyllum kochii Engl. & K.Krause > Sansevieria trifasciata Hort. ex Prain. Under the purification effect of each plant, the CO concentration in the chamber decreases linearly and significantly (p < 0.05), and within a specific time period, the time-weighted average (TWA) CO concentrations can be reduced to below the corresponding permissible exposure limits specified by some countries and organizations. (2) With the increase of the stomatal number of each plant and the increase in CO concentration, the hourly and cumulative absorbed CO of each plant increase linearly and significantly (p < 0.05). (3) With the increase in CO concentration, the CO purification efficiency of each plant decreases exponentially and significantly (p < 0.05). (4) When the CO concentration was ≤ 50 ppm, all plants could effectively purify CO without damage. When the CO concentration was in the range of 100 ~ 400 ppm, within 2 weeks after the 48-h experiment, the leaf tips of Chlorophytum comosum (Thunb.) Jacques and Epipremnum aureum (Linden ex André) G.S.Bunting were damaged one after another, and the damaged leaf area increased with the increase of CO concentration. However, each plant as a whole still survived. This study demonstrated that different species of potted plants can effectively absorb low concentrations of CO to varying degrees, but higher concentrations of CO will damage the survival of specific species of potted plants.

Pyloric stent insertion in malignant gastric outlet obstruction: moving beyond palliation.

BACKGROUND: Self-expandable metallic stents have not only largely replaced surgical gastrojejunostomy for unresectable gastric cancers, but their role as bridging therapy for resectable obstructing tumours is also evolving. OBJECTIVE: To evaluate the efficacy and safety of pyloric stents in gastric outlet obstruction in patients with gastric cancer and assess survival in patients with resectable obstructing gastric tumours in whom stents were inserted as a bridge to surgery. METHODS: We retrospectively reviewed the electronic medical records of patients who underwent self-expandable metallic stent insertion for gastric outlet obstruction due to gastric cancer from January 2014 to March 2019. RESULTS: Out of 161 patients, clinical improvement was observed in 159 (99%) and 156 (97%) at 1 and 12 weeks of stent placement, respectively. None of these patients experienced serious complications, such as perforation or aspiration pneumonia. Of these 161 patients, enteral stents were placed as bridging therapy prior to surgery in 40 (24.8%). Among these, 35 (87.5%) of 40 underwent neo-adjuvant chemotherapy followed by curative surgery. Of the 35 patients, 3 failed to follow-up. One-year survival following curative surgery was 87.5%. Stent helped to reduce vomiting and improve nutrition, measured by the body mass index (p = 0.36) and serum albumin (p = 0.05), over a 4-week period following stent insertion. CONCLUSION: Pyloric stents are useful in relieving malignant gastric outlet obstruction, maintaining nutrition during neo-adjuvant treatment and improving survival without additional risk of postoperative complications. They have traditionally been used for palliation, but should also be considered as bridging therapy for obstructing resectable gastric tumours during neo-adjuvant treatment.