Changes in the function of the anal sphincter complex and generated anal pressure at different anatomical levels after elastic ligature application in patients with anal fistula

Purpose: The purpose of the present study was to measure by means of especially developed apparatus the anal and intrarectal pressure before and after different operations for perianal fistulas as well as to correlate the degree of incontinence evaluated by Fecal Incontinence Severity Index (FISI) with changes in the measured pressures and type of operation used.Material and methods: The study covered 311 patients with perianal fistulas who were operated with several methods. Anal canal pressures at 5 different levels were measured by the especially developed apparatus at rest, squeezing and cough, before and after 6 months of operation. FISI form was used for incontinence detection.Results: Resting, squeezing and cough pressures were higher in men before and after operations. Average reduction of anal rest pressure by 10-15%, at contraction by 20-25% and at cough by 5-10% resulted in mild incontinence according to FISI score. Average reduction of anal rest pressure by 20-25%, at contraction by 30-40% and at cough by 20-25% correlated with postoperative moderate degree of incontinence according to FISI score. No severe incontinence was registered by FISI examination. Usage of the method of elastic ligation of perianal fistulas, i.e. the method of Hippocrates-Thoma Junescu caused the highest percentage of postoperative mild degree incontinence (15,9%) and moderate one (4,3%) by FISI. No patients presented with severe degree of incontinence.Conclusion: The method of anal sphincter tonometry demonstrated a significant reduction of anal pressure after surgery for anal fistulas. This objective decrease of anal sphincter tone correlated with the higher FISI score arguing of postoperative incontinence. The method of Hippocrates-Thoma-Junescu resulted in the highest rate of incontinence (around 20%) and anal pressure reduction

Open lateral sphincterotomy - A method of choice in the treatment of chronic anal fissure. Indications and results

Aim: The key to the treatment of chronic anal fissures is the reduction of the abnormal values of anal resting pressure. The aim of the surgical treatment is to reduce the activity of the internal anal sphincter and to provide proper conditions for the fissure to cure, which can be achieved by internal sphincterotomy. In the modern surgical practice the internal sphincterotomy is performed away from the fissure, lateral of the last, using open or closed technique.Methods: In our study we performed open lateral internal sphincterotomy (OLST) of 82 patients with chronic anal fissure, compared to a control group of 231 patients, treated with different methods. Results: We didn`t register any recurrences in the sixth post-operative moth after OLST. 11% of patients with OLST were with registered incontinence after the sixth post-operative month compared with 4.4% in non-OLST patients. The data was statistically significant (p=0.032)Conclusion: Choosing an OLST as a method for treatment of chronic anal fissure requires careful selection of patients. It is not recommended for patients with a risk of incontinence like those with a previous birth trauma, age beyond 60 years, previous ano-rectal operations, neurological diseases and low values in anal resting pressure.Aim: The key to the treatment of chronic anal fissures is the reduction of the abnormal values of anal resting pressure. The aim of the surgical treatment is to reduce the activity of the internal anal sphincter and to provide proper conditions for the fissure to cure, which can be achieved by internal sphincterotomy. In the modern surgical practice the internal sphincterotomy is performed away from the fissure, lateral of the last, using open or closed technique.Methods: In our study we performed open lateral internal sphincterotomy (OLST) of 82 patients with chronic anal fissure, compared to a control group of 231 patients, treated with different methods. Results: We didn`t register any recurrences in the sixth post-operative moth after OLST. 11% of patients with OLST were with registered incontinence after the sixth post-operative month compared with 4.4% in non-OLST patients. The data was statistically significant (p=0.032)Conclusion: Choosing an OLST as a method for treatment of chronic anal fissure requires careful selection of patients. It is not recommended for patients with a risk of incontinence like those with a previous birth trauma, age beyond 60 years, previous ano-rectal operations, neurological diseases and low values in anal resting pressure

Deroofing - a method of choice in the treatment of suppurative perineal hidradenitis

Purpose: Suppurative hidradenitis is a chronic relapsing inflammatory disease that affects the apocrine sweat glands. Therefore, it is most often located in the axilla, groin and perianal area. Usually, people of working age affected. Perineal and perianal locations cover about 37% of the total morbidity rate and are more common in males. The objective of this study was to share our experience with the application of deroofing for the treatment of purulent perineal hidradenitis.Material and methods: This prospective interventional study covered 13 patients with suppurative fistulasing hidradenitis of perineum treated in Division of Coloproctology and Septic Surgery, Georgi Stranski University Hospital of Pleven for the period from 2008 till 2013.Results: The interval between the occurrence of disease and its surgical treatment was very long - from two to 36 years (average of 9,2 years). It resulted from the progression of the disease with enlarged soft tissue involvement. Sometimes, the disease was complicated by chroniosepsis. The average hospital stay was 13,5-day long. Operative wounds healed secondarily at an average of about 30 days. The patients were followedup for six months, one year and two years. Two patients with relapses on the sixth postoperative month were hospitalized again. The surgical intervention warranted good results.Conclusion: Treatment of suppurative hidradenitis of the perineum is complex, both in terms of local status and systematic violations resulting in chronic infection. There are numerous surgical techniques for treating this pathology. The advantages of deroofing are the following: minimal trauma to the patient, application by using local anesthesia at the early stage in order to minimize hospital stay, no need of special equipment, a lower recurrence rate than the other methods and formation of aesthetically acceptable scar

Site-Specific Bioconjugation of a Murine Dihydrofolate Reductase Enzyme by Copper(I)-Catalyzed Azide-Alkyne Cycloaddition with Retained Activity

Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is an efficient reaction linking an azido and an alkynyl group in the presence of copper catalyst. Incorporation of a non-natural amino acid (NAA) containing either an azido or an alkynyl group into a protein allows site-specific bioconjugation in mild conditions via CuAAC. Despite its great potential, bioconjugation of an enzyme has been hampered by several issues including low yield, poor solubility of a ligand, and protein structural/functional perturbation by CuAAC components. In the present study, we incorporated an alkyne-bearing NAA into an enzyme, murine dihydrofolate reductase (mDHFR), in high cell density cultivation of Escherichia coli, and performed CuAAC conjugation with fluorescent azide dyes to evaluate enzyme compatibility of various CuAAC conditions comprising combination of commercially available Cu(I)-chelating ligands and reductants. The condensed culture improves the protein yield 19-fold based on the same amount of non-natural amino acid, and the enzyme incubation under the optimized reaction condition did not lead to any activity loss but allowed a fast and high-yield bioconjugation. Using the established conditions, a biotin-azide spacer was efficiently conjugated to mDHFR with retained activity leading to the site-specific immobilization of the biotin-conjugated mDHFR on a streptavidin-coated plate. These results demonstrate that the combination of reactive non-natural amino acid incorporation and the optimized CuAAC can be used to bioconjugate enzymes with retained enzymatic activityope

Catalytically active single-chain polymeric nanoparticles: exploring their functions in complex biological media

Dynamic single-chain polymeric nanoparticles (SCPNs) are intriguing, bioinspired architectures that result from the collapse or folding of an individual polymer chain into a nanometer-sized particle. Here we present a detailed biophysical study on the behavior of dynamic SCPNs in living cells and an evaluation of their catalytic functionality in such a complex medium. We first developed a number of delivery strategies that allowed the selective localization of SCPNs in different cellular compartments. Live/dead tests showed that the SCPNs were not toxic to cells while spectral imaging revealed that SCPNs provide a structural shielding and reduced the influence from the outer biological media. The ability of SCPNs to act as catalysts in biological media was first assessed by investigating their potential for reactive oxygen species generation. With porphyrins covalently attached to the SCPNs, singlet oxygen was generated upon irradiation with light, inducing spatially controlled cell death. In addition, Cu(I)- and Pd(II)-based SCPNs were prepared and these catalysts were screened in vitro and studied in cellular environments for the carbamate cleavage reaction of rhodamine-based substrates. This is a model reaction for the uncaging of bioactive compounds such as cytotoxic drugs for catalysis-based cancer therapy. We observed that the rate of the deprotection depends on both the organometallic catalysts and the nature of the protective group. The rate reduces from in vitro to the biological environment, indicating a strong influence of biomolecules on catalyst performance. The Cu(I)-based SCPNs in combination with the dimethylpropargyloxycarbonyl protective group showed the best performances both in vitro and in biological environment, making this group promising in biomedical applications