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Case Presentation: A 37-year-old woman presented with a 2-month history of recurrent hemoptysis and coughing. Her symptoms started 2 months after the delivery of her third child. In total, she endured four episodes of hemoptysis. All pregnancies were induced by intracytoplasmic sperm injections. She lacked a pulmonary or smoking history and had no history of foreign body aspiration or intubation. There was no dyspnea, dysphagia, fever, or chest pain, and the patient did not complain of purulent sputum. She currently did not use medication and was generally in good health., (Copyright © 2019 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

The mannopeptimycins (MPPs) are potent glycopeptide antibiotics that contain both D and L forms of the unique, arginine-derived amino acid beta-hydroxyenduracididine (betahEnd). The product of the mppO gene in the MPP biosynthetic cluster resembles several non-heme iron, alpha-ketoglutarate-dependent oxygenases, such as VioC and clavaminate synthase. The role of MppO in betahEnd biosynthesis was confirmed through inactivation of mppO, which yielded a strain that produced dideoxy-MPPs, indicating that mppO is essential for generating the beta-hydroxy functionality for both betahEnd residues. Characterization in vitro of recombinant His6-MppO expressed in E. coli revealed that MppO selectively hydroxylates the beta carbon of free L-enduracididine.

Background: Acetazolamide and medroxyprogesterone acetate (MPA) are two respiratory stimulants that can be used in patients with stable hypercapnic COPD., Design and Methods: The effects of acetazolamide, 250 mg bid, and MPA, 30 mg bid, on daytime and nighttime blood gas values and the influences on the hypercapnic and hypoxic ventilatory and mouth occlusion pressure (P(0.1)) at 100 ms response were studied in a crossover design in 12 hypercapnic patients with stable COPD (FEV(1), 33 +/- 4% predicted [mean +/- SEM])., Results: Daytime PaCO(2) decreased from 47.3 +/- 0.8 mm Hg (placebo) to 42.0 +/- 1.5 mm Hg during acetazolamide treatment (p < 0.05) and to 42.8 +/- 1.5 mm Hg during MPA treatment (p < 0.05). Daytime PaO(2) improved with acetazolamide from 65.2 +/- 2.3 to 75.0 +/- 3.0 mm Hg (p < 0.05), whereas no significant changes were seen with MPA. Mean nocturnal end-tidal carbon dioxide tension decreased with both treatments, from 42.0 +/- 2.3 to 35.3 +/- 2.3 mm Hg with acetazolamide (p < 0.05) and to 34.5 +/- 0.8 mm Hg with MPA (p < 0.05). The percentage of time that the nocturnal arterial oxygen saturation was < 90% was reduced significantly with acetazolamide, from 34.9 +/- 10.7% to 16.3 +/- 7.5% (p < 0.05). Mean nocturnal saturation did not change with MPA. Resting minute ventilation increased significantly only with MPA from 9.6 +/- 0.7 to 10.8 +/- 0.8 L/min (p < 0.05). The slope of the hypercapnic ventilatory response did not change during acetazolamide and MPA therapy. The hypoxic ventilatory response increased from - 0.2 +/- 0.05 to - 0.4 +/- 0.1 L/min/% during acetazolamide (p < 0.05) and to - 0.3 +/- 0.1 L/min/% during MPA (p < 0.05). The hypoxic P(0.1) response improved with acetazolamide treatment from - 0.05 +/- 0.008 to - 0.15 +/- 0.02 mm Hg/% (p < 0.05)., Conclusions: This study shows that acetazolamide and MPA both have favorable effects on daytime and nighttime blood gas parameters in ventilatory-limited patients with stable COPD. However, the use of acetazolamide is preferred because of its extra effect on nocturnal saturation.