You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Outcome", "Participant", "Intervention"].

Please return the output as a JSON object of the format: {"Participant" : ["patients with COPD", ...], "Intervention" : ["Atenolol", ...], "Outcome" : ["blood pressure", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

The effect of L-arginine and citrulline on endothelial function in patients in heart failure with preserved ejection fraction . BACKGROUND To evaluate the effect of the amino acids L-arginine and citrulline on endothelial function in patients in stable diastolic and right heart failure using photoplethysmography . METHODS Thirty patients from the Heart Failure Clinic of the Instituto Nacional de Ciencias Médicas y Nutrición " Salvador Zubirán " underwent photoplethysmography using the hyperemia technique . Index finger flow was assessed at baseline and after ischemia every 30 s by maximum amplitude time ( MAT ) , total time of the curve ( TT ) and the index of the two ( MAT/TT < 30 = normal ) before and after the administration of L-arginine ( 8 g/day in two doses , n = 15 ) or citrulline ( 3 g/day in one dose , n = 15 ) for 60 days in addition to optimal pharmacological treatment . RESULTS There were no statistically significant differences between the two groups at baseline . After the intervention , the MAT/TT index of all patients normalized in each evaluation period with statistically significant differences . Basal L-arginine group = 38.75 ± 11.52 , final 23.32 ± 6.08 , p = 0.007 and basal citrulline group = 41.4 ± 13.47 , final 23.65 ± 6.74 , p = 0.007 at 60-90 s. Post-ischemia : basal L-arginine 36.60 ± 11.51 , final 18.81 ± 15.13 , p = 0.004 and basal citrulline = 49.51 ± 15.17 , final 27.13 ± 7.87 , p = 0.003 . CONCLUSIONS The administration of L-arginine and citrulline has a beneficial effect on endothelial function as shown by the normalized MAT/TT index . It probably improves systemic and pulmonary hemodynamics , which could help in the treatment of diastolic heart failure .
{"Intervention": ["amino acids L-arginine and citrulline", "L-arginine and citrulline"], "Outcome": ["endothelial function"], "Participant": ["treatment of diastolic heart", "patients in stable diastolic and right heart failure", "Thirty patients", "Heart Failure Clinic of the Instituto Nacional de Ciencias M\u00e9dicas y Nutrici\u00f3n \" Salvador Zubir\u00e1n \" underwent photoplethysmography using the hyperemia technique", "patients in heart failure with preserved ejection fraction"]}