The photochemistry and photophysics of a series of S-nitrosothiols (RSNOs) have been studied computationally. The photocleavage mechanism of the model compound CH(3)SNO to release CH(3)S· and ·NO was studied at the CASPT2 level resulting in a barrierless process when irradiating in the visible region (S(1)), in the near UV region (S(2)) and for photosensitized (T(1)) reaction. The absorption energy required to initiate photocleavage was calculated at the CASPT2 and B3P86 levels showing the possibility of the modulation of NO release by RSNO photoactivation as a function of the substituent R. Good correlations between the wavelengths of the lowest energy (1)(n,π*) and (1)(π,π*) transitions of aryl S-nitrosothiols and the corresponding Hammett constants of the substituents have been obtained.
Percutaneous PTNS was effective in over 70% of patients in the present study with improvements in urgency, anal pressures and Wexner score.
A methodology for the prediction of excitation energies for substituted chromophores on the basis of ground state structures has been developed. The formalism introduces the concept of "structural substituent excitation energy effect" for the rational prediction and quantification of the substituent effect in the excitation energy of a chromophore to an excited electronic state. This effect quantifies exclusively the excitation energy variation due to the structural changes of the chromophore induced by the substituent. Therefore, excitation bathochromic and hypsochromic shifts of substituted chromophores can be predicted on the basis of known ground and excited potential energy surfaces of a reference unsubstituted chromophore, together with the ground state minimum energy structure of the substituted chromophore. This formalism can be applied if the chemical substitution does not affect the nature of the electronic excitation, where the substituent effect can be understood as a force acting on the chromophore and provoking a structural change on it. The developed formalism provides a useful tool for quantitative and qualitative determination of the excitation energy of substituted chromophores and also for the analysis and determination of the structural changes affecting this energy. The proposed methodology has been applied to the prediction of the excitation energy to the first bright state of several S-nitrosothiols using the potential energy surfaces of methyl-S-nitrosothiol as a reference unsubstituted chromophore.
BACKGROUND: Fistulotomy with immediate sphincteroplasty is a technique that can heal fistulas and decrease fecal incontinence more effectively than fistulotomy alone, in selected patients. OBJECTIVE: We aimed to perform a long-term evaluation of fecal incontinence after fistulotomy and immediate sphincteroplasty in patients with complex anal fistula. DESIGN: This prospective study included patients undergoing fistulotomy and immediate sphincteroplasty for complex anal fistula from January 2000 to December 2010. SETTINGS: The study was conducted by 2 colorectal surgeons in the coloproctology unit of the General Hospital of Elche. PATIENTS: We included patients aged ≥18 years with complex anal fistulas of cryptoglandular origin. MAIN OUTCOME MEASURES: Main outcomes were recurrence and continence after fistulotomy and immediate sphincteroplasty, according to fistula tract height and preoperative continence status. RESULTS: A total of 107 patients were included; 68.2% were men, with a mean age of 48 years and mean fistula duration of 12.8 months. The range and median follow-up period were 84 to 204 and 96 months. Thirty-seven fistulas were not primary. The overall healing rate was 84.1%. Primary fistulas healed by the end of follow-up in 58 (82.9%) of 70 patients; recurrent fistulas healed in 32 (86.5%) of 37; high tracts healed in 31 (83.8%) of 37, and nonhigh fistulas healed in 59 (84.3%) of 70. Male sex (OR = 0.66 (95% CI, 0.20–2.13); p > 0.05) and recurrent fistulas (OR = 0.43 (95% CI, 0.11–1.68); p > 0.05) could have a protective effect against postoperative fecal incontinence; however, more studies with larger sample sizes are necessary to confirm this result, whereas high fistulas showed a 4-fold increased risk of incontinence (range, 1.22–13.06; p < 0.01). One in 5 high-tracts patients experienced continence deterioration. LIMITATIONS: This was a prospective study, and randomized clinical trials with more patients and longer follow-up are needed to compare fistulotomy and immediate sphincteroplasty with other sphincter-preserving techniques. CONCLUSIONS: Fistulotomy and immediate sphincteroplasty are good options for treating complex anal fistulas, especially for recurrent fistulas, men, and patients with nonhigh tracts, with acceptable recurrence and incontinence rates. See Video Abstract at http://links.lww.com/DCR/B498. EVALUACIÓN A LARGO PLAZO DE LA FISTULOTOMÍA Y LA ESFINTEROPLASTIA INMEDIATA COMO TRATAMIENTO PARA LA FÍSTULA ANAL COMPLEJA ANTECEDENTES: La fistulotomía y la esfinteroplastia inmediata es una técnica que puede curar las fístulas y disminuir la incontinencia fecal de manera más efectiva que la fistulotomía sola, en pacientes seleccionados. OBJETIVO: Nuestro objetivo fue realizar una evaluación a largo plazo de la incontinencia fecal después de la fistulotomía y la esfinteroplastia inmediata en pacientes con fístula anal compleja. DISEÑO: Este estudio prospectivo incluyó pacientes sometidos a fistulotomía y esfinteroplastia inmediata por fístula anal compleja, desde enero d...
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