A cost-utility study of elective haemorrhoidectomies in Canada.

AIM: The aim was to estimate the 10-year cost-utility of haemorrhoidectomy surgery with preference-based measures of health using Canadian health utility measures and costs. METHODS: Patients undergoing elective haemorrhoidectomies by general and colorectal surgeons in British Columbia, Vancouver, between September 2015 and November 2022, completed preoperatively and postoperatively the EuroQol five-dimension five-level health-related quality of life questionnaire (EQ-5D-5L). Quality-adjusted life years (QALYs) attributable to surgery were calculated by discounting preoperative and postoperative health utility values derived from the EQ-5D-5L. Costs were measured from a health system perspective which incorporated costs of hospital stay and specialists' fees. Results are presented in 2021 Canadian dollars. RESULTS: Of 94 (47%) patients who completed both the preoperative and postoperative questionnaires, the mean gain in QALYs 10 years after surgery was 1.0609, assuming a 3.5% annual discounting rate. The average cost of the surgery was $3166. The average cost per QALY was $2985 when benefits of the surgery were assumed to accrue for 10 years. The cost per QALY was higher for women ($3821) compared with men ($2485). Participants over the age of 70 had the highest cost per QALY ($8079/QALY). CONCLUSIONS: Haemorrhoidectomies have been associated with significant gains in health status and are inexpensive relative to the associated gains in quality of life based on patients' perspectives of their improvement in health and well-being.

Transanal versus conventional total mesorectal excision for rectal cancer using the IDEAL framework for implementation.

BACKGROUND: Transanal total mesorectal excision (TaTME) is an innovative technique for distal rectal cancer dissection. It has been shown to have similar short-term outcomes to conventional open and laparoscopic total mesorectal excision (cTME), but recent studies have raised concern about increased morbidity and local recurrence rates. The aim of this study was to assess outcomes after TaTME versus cTME for rectal cancer. METHODS: TaTME was implemented in 2014 using IDEAL principles in a single institution. The institution maintains databases for all patients undergoing rectal cancer surgery. This retrospective review compared data collected from all patients who had TaTME with those from a propensity-matched cohort of patients who underwent cTME. The primary outcome was a composite pathological measure combining margin status and quality of total mesorectal excision (TME). Short-term clinical and survival outcomes were also measured. RESULTS: Propensity matching created 109 matched pairs for analysis. Nine patients (8.3 per cent) undergoing TaTME had positive margins and/or incomplete TME, compared with 11 (10.5 per cent) undergoing cTME (P = 0.65). There were no significant differences in morbidity between the TaTME and cTME groups, including number of anastomotic leaks (13.8 versus 18.3 per cent; P = 0.37). The estimated 3-year local recurrence-free survival rate was 96.3 per cent in both groups (P = 0.39). Estimated 3-year overall (93.6 per cent for TaTME versus 94.5 per cent for cTME; P = 0.09) and disease-free (88.1 versus 76.1 per cent; P = 0.90) survival rates were similar. CONCLUSION: TaTME provided similar outcomes to cTME for rectal cancer with the application of IDEAL principles.

Transanal Endoscopic Microsurgery (TEM) for rectal GI stromal tumor.

BACKGROUND: Transanal endoscopic microsurgery (TEM) is effective in treating adenomas and select early rectal cancers. Our objective is to evaluate TEM in treating early rectal GISTs. METHODS: Patients were identified in a prospective database with pathology confirmed rectal GIST prior to TEM over 10 years. Demographic, pathologic, operative and follow-up data was analysed and presented with descriptive statistics. RESULTS: 7 cases of rectal GIST were treated with TEM with a follow-up time of 31 months (0-71). Median tumor distance from the anal verge was 4 cm (2.5-6) and median tumor size was 3 cm (2-5.7). Negative margins were achieved in 4/7 patients. Those with positive margins were treated with repeat TEM or imatinib. 1 patient had local recurrence successfully treated by TEM. CONCLUSIONS: Overall, TEM is safe for locally excising GISTs. As rectal GISTs are rare, a multicenter registry may better elucidate outcomes with this treatment.

Health and quality of life among a cohort of patients having lateral internal sphincterotomy for anal fissures.

AIM: The aim of this study is to report changes in health-related quality of life attributable to lateral internal sphincterotomy for treatment of anal fissure. There is very little evidence on whether the overall health-related quality of life of patients is detrimentally affected by the condition, or which aspects of self-perceived health status improve after lateral internal sphincterotomy. This study will articulate which aspects of health tend to improve and guide postoperative expectations appropriately. Knowledge gained from this study may also identify gaps in an individual patient's episode of care. METHOD: Patients were prospectively identified when they consented to surgical treatment of their anal fissure and were contacted by phone to participate. Participants completed a number of patient-reported outcomes preoperatively and 6 months postoperatively. Faecal incontinence-related quality of life, pain and depression were measured at both time points. The severity of faecal incontinence was measured at both times. RESULTS: Participants reported high levels of pain preoperatively. Postoperatively, improvement in pain exceeded the threshold of clinical relevance (P < 0.01). Thirty-five per cent of participants reported significant effects of faecal incontinence preoperatively, while 26% did so postoperatively. Participants with multiple comorbidities were more likely to report faecal incontinence postoperatively than preoperatively. CONCLUSION: This study reports that lateral internal sphincterotomy improved pain symptoms without adverse effects on continence. Not all domains of health-related quality of life were similarly positively affected by anal fissure repair.

Surgical site infection in elective colonic and rectal resections: effect of oral antibiotics and mechanical bowel preparation compared with mechanical bowel preparation only.

AIM: Surgical site infections are disproportionately common after colorectal surgery and may be largely preventable. The objective of this retrospective cohort study was to determine the effect of oral antibiotics and mechanical bowel preparation on surgical site infections. METHOD: A retrospective study of a consecutive series of elective colonic and rectal resections following an Enhanced Recovery After Surgery pathway, which also included mechanical bowel preparation, from 1 September 2014 to 30 September 2017. The addition of oral antibiotics (neomycin and metronidazole) to the mechanical bowel preparation procedure was assessed. Development of surgical site infections within 30 days was the main outcome measured. The secondary outcome was assessment of possible surgical site infection predictors. RESULTS: Seven-hundred thirty-two patients were included: 313 (43%) preintervention (mechanical bowel preparation only); and 419 (57%) postintervention (mechanical bowel preparation plus oral antibiotics). Surgical site infection rates preintervention and. postintervention were: overall, 20.8% vs 10.5%, P < 0.001; superficial, 10.9% vs 4.3%, P < 0.001; and organ space, 9.9% vs 6.2%, P = 0.03. Subgroup analysis of colonic resections revealed a significant reduction in overall (17.1% vs 6.8%), superficial (10.7% vs 4.3%) and organ space (6.4% vs. 2.6%) infections. Rectal resections had significant reduction in overall (26.2% vs 15.3%) and superficial (11.1% vs 4.4%) infection rates but not in organ space infections (15.1% vs 10.9%). Multivariate regression analysis revealed open vs minimally invasive surgery (P < 0.001) and omission of oral antibiotics (P = 0.004) as independent predictors of surgical site infections. CONCLUSION: Administration of oral antibiotics resulted in significant reduction of superficial and organ space infections after colonic resection; after rectal resection, significant reduction only of superficial infections was found.

A multi-centre randomized controlled trial of open vs closed management of the rectal defect after transanal endoscopic microsurgery.

AIM: Transanal endoscopic microsurgery (TEM) is a technically challenging strategy that allows expanded indications for local excision of rectal lesions. Transluminal suturing is difficult, so open management of the resultant defect is appealing. Expert opinion suggests there is more pain when the defect is left open. The aim of this study was to determine if closure of the defect created during full thickness excision of rectal lesions with TEM leads to less postoperative pain compared to leaving the defect open. METHOD: At the time of surgery, patients undergoing a full thickness TEM were randomized to sutured (TEM-S) or open (TEM-O) management of the rectal defect. At five Canadian academic colorectal surgery centres, experienced TEM surgeons enrolled patients ≥ 18 years treated by full thickness TEM. The primary outcome was postoperative pain measured by the visual analogue scale. Secondary outcomes included postoperative pain medication use and 30-day postoperative complications, including bleeding, infection and hospital readmission. RESULTS: Between March 2012 and October 2013, 50 patients were enrolled and randomized to sutured (TEM-S, n = 28) or open (TEM-O, n = 22) management of the rectal defect. There was no difference between the two study groups in postoperative pain on postoperative day 1 (2.8 vs 2.6, P = 0.76), day 3 (2.8 vs 2.1, P = 0.23) and day 7 (2.8 vs 1.7, P = 0.10). CONCLUSION: In this multicentre randomized controlled trial, there was no difference in postoperative pain between sutured or open defect management in patients having a full thickness excision with TEM.

Transanal endoscopic microsurgery as day surgery - a single-centre experience with 500 patients.

AIM: Transanal endoscopic microsurgery (TEM) is the current treatment of choice for rectal adenomas and early rectal cancer. Postoperative admission to hospital is common but possibly unnecessary. Our objective was to analyse predictors and outcomes of TEM patients having same day discharge (TEM-D) compared with those who were admitted to hospital (TEM-A). METHOD: At St Paul's Hospital (SPH), demographic, surgical, pathological and follow-up data have been collected prospectively since TEM was started in 2007. Trends in admission and readmission rates were analysed using the Cochran-Armitage trend test, and predictors of admission were analysed using univariate and multivariate logistic regressions. RESULTS: Between 2007 and 2016, 500 patients were treated by TEM at SPH. The overall admission rate was 29% (145/500), but this decreased to 19% in the last 3 years of the study (P < 0.001). The readmission rate was 5.2% (n = 26/500) and did not change significantly over the study period (P = 0.30). Reasons for admission included the following: surgeon discretion/monitoring (35%), urinary retention (26%), haemorrhage (10%), breach of peritoneal cavity (7%), infection (7%) and other (15%). The most common reasons for readmission were haemorrhage (54%, n = 14), pain (19%, n = 5) and infection (12%, n = 3). Factors associated with admission were as follows: tumour height (OR 1.09, 1.02-1.17), prolonged operative time (OR 1.25, 1.14-1.37), unsutured surgical defect (OR 1.99, 1.22-3.25) and surgeon experience (OR 4.62, 2.75-7.77). CONCLUSION: Outpatient TEM is safe and carries a low risk of readmission. In centres with an outpatient TEM strategy, predictors of hospital admission include proximal tumours, prolonged surgical time and open management of the surgical defect.

Salvage TME following TEM: a possible indication for TaTME.

BACKGROUND: Salvage surgery after transanal endoscopic microsurgery (TEM) has shown mixed results. Transanal total mesorectal excision (TaTME) might be advantageous in this population. The aim of this study was to assess the short-term oncologic and operative outcomes of salvage surgery after TEM, comparing TaTME to conventional salavge TME (sTME). METHODS: Consecutive patients treated with salvage surgery after TEM were identified. Patients who underwent TaTME were compared to those who had conventional sTME. The primary outcome was the ability to perform an appropriate oncologic procedure defined by a composite outcome (negative distal margins, negative radial margins and complete or near complete mesorectum specimen). RESULTS: During the study period, 41 patients had salvage surgery after TEM. Of those, 11 patients had TaTME while 30 patients had sTME. All patients in the TaTME group met the composite outcome of appropriate oncologic procedure compared to 76.7% for the conventional sTME group (p = 0.19). TaTME was associated with significantly higher rates of sphincter preservation (100 vs. 50%, p = 0.01), higher rates of laparoscopic surgery (100 vs. 23.3%, p < 0.001) and lower rates of conversion to open surgery (9.1 vs. 57%, p < 0.001). No difference was found in postoperative morbidity (36.3 vs. 36.7%, p = 0.77). CONCLUSIONS: The present study demonstrates that for patients requiring salvage surgery after TEM, TaTME is associated with significantly higher rates of sphincter-sparing surgery when compared to conventional transabdominal TME while producing adequate short-term oncologic outcomes. Salvage surgery after TEM might be a clear indication for TaTME rather than conventional surgery.

Randomized double-blind trial comparing the cosmetic outcome of cutting diathermy versus scalpel for skin incisions.

BACKGROUND: Controversy exists about whether cutting diathermy for skin incisions leads to a cosmetically inferior scar. Cosmetic outcomes were compared between skin incisions created with cutting diathermy versus scalpel. Wound infection rates and postoperative incisional pain were also compared. METHODS: This was a randomized double-blind trial comparing cutting diathermy and scalpel in patients undergoing bowel resection. Scar cosmesis was assessed at 6 months after surgery by a plastic surgeon and a research associate using the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scale (POSAS). Patients also used POSAS to self-evaluate their scars. Wound infections within 30 days were recorded, and incision pain scores were measured on the first 5 days after operation. RESULTS: A total of 66 patients were randomized to cutting diathermy (31) or scalpel (35). At 6 months, there was no significant difference between the diathermy and scalpel groups in mean(s.d.) VSS scores (4·9(2·6) versus 5·0(1·9); P = 0·837), mean POSAS total scores (19·2(8·0) versus 20·0(7·4); P = 0·684) or subjective POSAS total scores (20·2(12·1) versus 21·3(10·4); P = 0·725). Neither were there significant differences in wound infection rates between the groups (5 of 30 versus 5 of 32; P = 1·000). Pain scores on day 1 after operation were significantly lower in the diathermy group (mean 1·68 versus 3·13; P = 0·018), but were not significantly different on days 2-5. CONCLUSION: Cutting diathermy is a cosmetically acceptable technique for abdominal skin incisions. There is no increased risk of wound infection, and diathermy may convey benefit in terms of early postoperative wound pain. REGISTRATION NUMBER: NCT01496404 ( http://www.clinicaltrials.gov).

Development and Validation of Stability-indicating RP-HPLC Method for Estimation of Pamabrom in Tablets.

The present study depicts the development of a validated RP-HPLC method for the determination of the pamabrom in presence of degradation products or other pharmaceutical excipients. Stress study was performed on pamabrom and it was found that it degrade sufficiently in acidic, alkali and oxidative condition but less degradation was found in thermal and photolytic condition. The separation was carried out on Enable G 120 A(0) (250×4.6 mm, 5 µ) column having particle size 5 µ using methanol: water (75:25 v/v) with pH 4.0 adjusted with ortho phosphoric acid as mobile phase at flow rate of 1 ml/min. The wavelength of the detection was 280nm. A retention time (Rt) nearly 3.9 min was observed. The calibration curve for pamabrom was linear (r (2) = 0.9997) from range of 10-60 µg/ml with limit of detection and limit of quantification of 1.41 µg/ml and 4.28 µg/ml, respectively. Analytical validation parameter such as selectivity, specificity, linearity, accuracy and precision were evaluated and relative standard deviation value for all the key parameters were less than 2.0%. The recovery of the drug after standard addition was found to be 101.35%. Thus, the developed RP-HPLC method was found to be suitable for the determination of pamabrom in bulk as well as stability samples of tablets containing various excipients.

New encoded single-indicator sequences based on physico-chemical parameters for efficient exon identification.

The first step in gene identification problem based on genomic signal processing is to convert character strings into numerical sequences. These numerical sequences are then analysed spectrally or using digital filtering techniques for the period-3 peaks, which are present in exons (coding areas) and absent in introns (non-coding areas). In this paper, we have shown that single-indicator sequences can be generated by encoding schemes based on physico-chemical properties. Two new methods are proposed for generating single-indicator sequences based on hydration energy and dipole moments. The proposed methods produce high peak at exon locations and effectively suppress false exons (intron regions having greater peak than exon regions) resulting in high discriminating factor, sensitivity and specificity.

Cryptococcal choroid plexitis: rare imaging findings of central nervous system cryptococcal infection in an immunocompetent individual.

Central nervous system (CNS) cryptococcosis is a common opportunistic fungal infection in immunocompromised patients, and the imaging findings differ from those in immunocompetent patients. Here, we present the imaging findings in an immunocompetent woman of a rare case of central nervous system cryptococcal choroid plexitis with trapped temporal horns, enlarged enhancing bilateral choroid plexuses and multiple intraventricular choroid plexus cysts.

The mystery of oxygen evolution: analysis of structure and function of photosystem II, the water-plastoquinone oxido-reductase.

Photosystem II (PS II) of thylakoid membrane of photosynthetic organisms has drawn attention of researchers over the years because it is the only system on Earth that provides us with oxygen that we breathe. In the recent past, structure of PS II has been the focus of research in plant science. The report of X-ray crystallographic structure of PS II complex by the research groups of James Barber and So Iwata in UK is a milestone in the area of research in photosynthesis. It follows the pioneering and elegant work from the laboratories of Horst Witt and W. Saenger in Germany, and J. Shen in Japan. It is time to analyze the historic events during the long journey made by the researchers to arrive at this point. This review makes an attempt to critically review the growth of the advancement of concepts and knowledge on the photosystem in the background of technological development. We conclude the review with perspectives on research and technology that should reveal the complete story of PS II of thylakoid in the future.

Comparative modelling of tetramanganese cluster of Chaetosphaeridium globosum.

The DI protein of photosystem II (PS II) complex of a microalga Chaetosphaeridium globosum has been theoretically modelled from its sequence using comparative modeling with known backbone structure of DI protein from bacterium Thermosynechococcus vulcanus as template. The model is built with missing loops and all side chains, which are not resolved in the structure of the template. The structure of the tetramanganese cluster (TMC) and the ligand forming side chains have been subjected to modeling studies in order to gather more information useful to understanding of the water splitting reactions. Earlier models of TMC have been scrutinized and an insight into the manganese coordination sphere has been provided.

A model for the organization of chlorophyll-protein complex of photosystem II and analysis of its photochemical efficiency and excitation migration.

A model is proposed for the organization of chlorophyll-protein complex in photosystem II (PS II) of higher plants. The rates of exciton migration and exciton trapping have been computed using stochastic method to find out the photochemical efficiency of the dimeric PS II. Three dimeric PS II units are assumed to form a group, as transfer of the exciton to the light harvesting bed of the nearest neighbour on either side may only be effective. A relationship has been deduced between the fractions of the reaction centre traps closed and the number of jumps (J) required by the exciton for trapping. The photochemical efficiency and fluorescence quantum yield are computed using J as the parameter in an empirical equation.

Modelling a binuclear metal binding site in the photosynthetic reaction centre II.

Based on the experimental data and homologous sites in Protein Data Bank (PDB) a model for metal binding sites in D1/D2 heterodimer has been proposed. On searching for tetranuclear and binuclear Mn binding sites in the PDB, a suitable sequence homology in thermolysin and D1 could be observed. From the homology and site-directed mutagenesis data, a model for binuclear Mn-Ca or Mn-Mn has been built and it is extended to a tetranuclear Mn centre.

Coated silica tips for use in high-pressure, high-temperature, scanning tunneling microscopy.

A novel application of coated silica tips for use in high-pressure, high-temperature, scanning tunneling microscopy is introduced. Thermal drift is reduced in the Z-direction due to the low thermal expansion of silica. Virtually, any conducting material that can be evaporated or sputtered can be used as a tip material. Experimental results are shown for tips sputter coated with platinum, along with images obtained.