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Objectives: To explore the knowledge, attitudes, and beliefs related to pessary use in Spanish-speaking women along the US-Mexico border., Methods: Spanish-speaking women with symptoms of vaginal bulge were recruited from the urogynecology/gynecology clinics at Texas Tech University Health Sciences Center El Paso to participate in moderated focus groups. Discussion topics included knowledge of prolapse/pessaries, pros/cons of pessaries, alternatives, and prolapse surgery. Audio-recorded group discussions were transcribed verbatim, and qualitative analysis completed by independent review using grounded theory methodology. Common themes were identified and then aggregated to form consensus concepts, agreed upon by the reviewers., Results: Twenty-nine Spanish-speaking women participated in 6 focus group discussions. Approximately half of women reported little or no prior knowledge about pessaries. Three main themes were identified from analysis: knowledge/perceptions, misinformation/misconceptions, and surgery-related concerns. Concepts identified from common themes included limited knowledge of pessaries, confusing "pessary" with "mesh," willingness to try pessaries in order to avoid surgery, desire to try pessary if it was recommended by physician, limited efficacy or complications of surgery, and mesh-related concerns. Interestingly, some women reported that pessaries appear to be a treatment more often offered in the United States rather than in Mexico., Conclusions: Most participants showed a willingness to try a pessary for symptoms of pelvic organ prolapse in an effort to avoid surgery, despite expressing limited knowledge about this treatment. Physician recommendations and risks of pessary use influence their likelihood of trying a pessary. These concepts serve as focus points for effective pessary counseling to help improve education and informed decision making in this patient population., Competing Interests: The authors have declared they have no conflicts of interest., (Copyright © 2020 American Urogynecologic Society. All rights reserved.)

ATP synthesis and the acceleration of the decay of the carotenoid absorption band shift after single flash excitation of Rhodopseudomonas capsulata chromatophores were compared. The two processes behave similarly with respect to: (1) ADP and Pi concentration; (2) inhibition by efrapeptin and venturicidin, and (3) inhibition by valinomycin/K+ and by ionophores. Taken together with earlier evidence for the electrochromic nature of the carotenoid band shift the data support the contention that positive charge moves outwards across the chromatophore membrane during ATP synthesis and justify the method for determination of the H+/ATP ratio (Petty, K.M. and Jackson, J.B. (1979) FEBS Lett. 97, 367-372). The ability of nucleotide diphosphates in the presence of Pi and Mg2+ to give rise to the acceleration of the carotenoid shift decay closely correlates with the rate of phosphorylation of the nucleotides in steady-state light. Nucleotide triphosphates enhance the decay in parallel with their rate of hydrolysis. Adenylyl imidodiphosphate is itself without effect on the decay of the carotenoid shift and it does not prevent the ADP-induced acceleration. The analogue does prevent the ATP effect but only after repeated flashes.

The reduced minus oxidized extinction coefficients (delta epsilon-red-ox) of reaction center P605 when in the chromatophore is about 20% smaller than in the detergent-isolated state. Presumably the coupling of the reaction center protein to the antenna bacteriochlorophylls and carotenoids causes this hypochromism. The chromatophore values for P605 are 19.5 mM- minus 1 times cm- minus 1 with the spectrophotometer on single beam mode at 605 nm, and 29.8 mM- minus 1 times cm- minus 1 on dual wavelength mode set at 605--540 nm. Cytochrome c2, which is not affected by detergent, has a delta epsilon-red-ox value at 550--540 nm of 19.0 mM- minus 1 times cm- minus 1.2. The total bacteriochlorophyll to reaction center bacteriochlorophyll protein (P) ratio is about 100: 1. The cytochrome c2: reaction center protein ratio approaches 2. In current French press chromatophore preparations, about 70% of the reaction centers are each associated on a rapid kinetic basis with two cytochrome c2 molecules (intact P-c2 units). The remaining reaction center proteins are not associated with cytochrome c2 on a kinetically viable bais and may be the result of damage incurred during mechanical rupture of the cells. 3...

ATP synthesis was measured after chromatophores from Rhodopseudomonas capsulata had been subjected to illumination by single turnover flashes fired at variable frequencies. Three processes were examined, which under different conditions can limit the net yield of ATP. (1) A process with an apparent relaxation time of 10-20 ms. This reaction probably limits the rate of ATP synthesis in continuous illumination. It has similar time dependence to the stimulation of the carotenoid shift decay by ADP after a single flash. (2) An active state of the ATPase only persists when the chromatophores are excited more often than once in 10 s. This state decays with similar kinetics to the entire carotenoid shift decay. Full activation is achieved after two flashes. (1) and (2) are not significantly affected by concentrations of antimycin A sufficient to block electron flow through the cytochrome b/c2 oxidoreductase and abolish phase III in the generation of the carotenoid shift. (3) In the presence of antimycin A, after the third, fourth and subsequent flashes ATP synthesis is limited by the quantity of reducing equivalents transported through the reaction centre rather than by the level of the electrochemical proton gradient.