Reconstructive techniques following low anterior resection for carcinoma of the rectum: meta-analysis.

BACKGROUND: Multiple trials have compared reconstruction techniques used following the resection of distal rectal cancers, including straight colorectal anastomosis (SCA), colonic J pouch (CJP), side-to-end anastomosis (SEA), and transverse coloplasty (TCP). The latest meta-analysis on the subject concluded that all the reservoir techniques produce equally good surgical and functional outcomes compared with SCA. Numerous trials have been published in this regard subsequently. Hence, a network analysis (NMA) was performed to rank these techniques. METHODS: A literature search of MEDLINE, Embase, and the Cochrane Library from their inception until April 2021 was conducted to identify randomized trials. Functional and surgical outcome data were pooled. ORs and standardized mean differences (MDs) were used as pooled effect size measures. A frequentist NMA model was used. RESULTS: Thirty-two trials met the eligibility criteria comprising 3072 patients. CJP showed better functional outcomes, such as low stool frequency and better incontinence score, both in the short term (stool frequency, MD -2.06, P < 0.001; incontinence, MD -1.17, P = 0.007) and intermediate term (stool frequency, MD -0.81, P = 0.021; incontinence MD -0.56, P = 0.083). Patients with an SEA (long-term OR 4.37; P = 0.030) or TCP (long-term OR 5.79; P < 0.001) used more antidiarrheal medications constantly. The urgency and sensation of incomplete evacuation favoured CJP in the short term. TCP was associated with a higher risk of anastomotic leakage (OR 12.85; P < 0.001) and stricture (OR 3.21; P = 0.012). CONCLUSION: Because of its better functional outcomes, CJP should be the reconstruction technique of choice. TCP showed increased anastomotic leak and stricture rates, warranting judicious use.

Early versus delayed surgery following neoadjuvant chemoradiation for esophageal cancer: a systematic review and meta-analysis.

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) followed by surgery, is the mainstay of managing locally advanced esophageal cancer. However, the optimal timing of surgery after neoadjuvant therapy is not defined clearly. METHODS: A systematic search of PubMed, Embase and Cochrane databases was conducted. 6-8 weeks were used as a cut-off to define early and delayed surgery groups. Overall Survival (OS) was the primary outcome, whereas pathological complete resolution (pCR), R0 resection, anastomotic leak, perioperative mortality, pulmonary complications, and major complication (> Clavien-Dindo grade 2) rates were secondary outcomes. Cohort studies and national registry bases studies were analysed separately. Survival data were pooled as Hazard Ratio (HR) and the rest as Odds Ratio (OR). According to heterogeneity, fixed-effect or random-effect models were used. RESULTS: Twelve retrospective studies, one RCT, and six registry-based studies (13,600 participants) were included. Pooled analysis of cohort studies showed no difference in OS (HR 1.03, CI 0.91-1.16), pCR (OR 0.98, CI 0.80-1.20), R0 resection (OR 0.90, CI 0.55-I.45), mortality (OR 1.03, CI 0.59-1.77), pulmonary complications (OR 1.26, CI 0.97-1.64) or major complication rates (OR 1.29, CI 0.96-1.73). Delayed surgery led to increased leak (OR 1.48, CI 1.11-1.97). Analysis of registry studies showed that the delayed group had a better pCR rate (OR 1.12, CI 1.01-1.24), with no improvement in survival (HR 1.01, CI 0.92-1.10). Delayed surgery was associated with increased mortality (OR 1.35, CI 1.07-1.69) and major complication rate (OR 1.55, CI 1.20-2.01). Available RCT reported surgical outcomes only. CONCLUSION: National registry-based studies' analysis shows that delay in surgery is riskier and leads to higher mortality and major complication rates. Further, well-designed RCTs are required.

Formation of 6H-Ba3Ce0.75Mn2.25O9 during Thermochemical Reduction of 12R-Ba4CeMn3O12: Identification of a Polytype in the Ba(Ce,Mn)O3 Family.

The resurgence of interest in a hydrogen economy and the development of hydrogen-related technologies has initiated numerous research and development efforts aimed at making the generation, storage, and transportation of hydrogen more efficient and affordable. Solar thermochemical hydrogen production (STCH) is a process that potentially exhibits numerous benefits such as high reaction efficiencies, tunable thermodynamics, and continued performance over extended cycling. Although CeO2 has been the de facto standard STCH material for many years, more recently 12R-Ba4CeMn3O12 (BCM) has demonstrated enhanced hydrogen production at intermediate H2/H2O conditions compared to CeO2, making it a contender for large-scale hydrogen production. However, the thermo-reduction stability of 12R-BCM dictates the oxygen partial pressure (pO2) and temperature conditions optimal for cycling. In this study, we identify the formation of a 6H-BCM polytype at high temperature and reducing conditions, experimentally and computationally, as a mechanism and pathway for 12R-BCM decomposition. 12R-BCM was synthesized with high purity and then controllably reduced using thermogravimetric analysis (TGA). Synchrotron X-ray diffraction (XRD) data is used to identify the formation of a 6H-Ba3Ce0.75Mn2.25O9 (6H-BCM) polytype that is formed at 1350 °C under strongly reducing pO2. Density functional theory (DFT) total energy and defect calculations show a window of thermodynamic stability for the 6H-polytype consistent with the XRD results. These data provide the first evidence of the 6H-BCM polytype and could provide a mechanistic explanation for the superior water-splitting behaviors of 12R-BCM.

Reconstructive techniques following low anterior resection for carcinoma of the rectum.

INTRODUCTION: Multiple reconstructive techniques have been described for reconstruction after a low anterior resection for carcinoma rectum. Colonic J pouch (CJP), Side to end anastomosis (SEA), transverse coloplasty pouch (TCP) and Straight Colo-rectal/anal anastomosis were the most widely studied. EVIDENCE ACQUISITION: PubMed, Embase and Cochrane data base were searched for randomized, non-randomized studies and systematic reviews from inception of the databases till July 31st, 2023. EVIDENCE SYNTHESIS: Considerable heterogeneity existed among different study findings. Reservoir techniques, including CJP, SEA, and TCP, exhibited reduced stool frequency, decreased urgency, and improved continence status compared to SCA, particularly in the short term. CJP maintained this advantage into the intermediate term. Other functional outcomes were similar among the techniques. However, these functional improvements did not translate into enhanced Quality of Life (QoL). TCP was associated with an elevated risk of anastomotic leaks. Other surgical outcomes remained comparable across all four techniques. Sexual outcomes also exhibited no significant variation. Some studies suggested that the size of the side limb in CJP or SEA may not significantly impact functional outcomes, implying that neorectum capacity may not be the primary determinant of improved function. The precise physiological mechanism underlying these findings remains unknown. CONCLUSIONS: In the short and intermediate terms, reservoir techniques demonstrated superior functional outcomes, but long-term performance was comparable among all techniques. Notably, enhanced functional outcomes did not translate to improved Quality of Life. TCP, while effective, is linked to an increased risk of anastomotic complications, necessitating cautious utilization.

Successful Management of Aorto-Oesophageal Fistula Following Accidental Ingestion of Chicken Bone.

Accidental ingestion of foreign bodies is common in clinical practice. It is usually seen to pass through the gastrointestinal tract easily. However, in the case of impaction in the esophagus, it can lead to catastrophic conditions. Aorto-esophageal fistula is one such disastrous complication with a high fatality rate. Despite treatment, mortality rates of up to 80% have been reported in the literature, with the condition being uniformly fatal in untreated patients. We describe a case of aorto-esophageal fistula secondary to a chicken bone impaction presenting with sentinel hemorrhage and managed expeditiously and successfully with simultaneous endoscopic removal and surgical repair of the fistula.

Defect graph neural networks for materials discovery in high-temperature clean-energy applications.

We present a graph neural network approach that fully automates the prediction of defect formation enthalpies for any crystallographic site from the ideal crystal structure, without the need to create defected atomic structure models as input. Here we used density functional theory reference data for vacancy defects in oxides, to train a defect graph neural network (dGNN) model that replaces the density functional theory supercell relaxations otherwise required for each symmetrically unique crystal site. Interfaced with thermodynamic calculations of reduction entropies and associated free energies, the dGNN model is applied to the screening of oxides in the Materials Project database, connecting the zero-kelvin defect enthalpies to high-temperature process conditions relevant for solar thermochemical hydrogen production and other energy applications. The dGNN approach is applicable to arbitrary structures with an accuracy limited principally by the amount and diversity of the training data, and it is generalizable to other defect types and advanced graph convolution architectures. It will help to tackle future materials discovery problems in clean energy and beyond.

IgG4-Related Pancreato-Biliary Disease in the Disguise of Malignancy.

The Immunoglobulin G4-related disease (IgG4-RD) is a multisystem inflammatory condition. Pancreaticobiliary manifestations often present as mass lesions that mimic malignancies. The diagnosis is confirmed by histopathological examination, that shows lymphoplasmacytic infiltration, storiform fibrosis, obliterative phlebitis, and positive immunohistochemistry for IgG4. We encountered 3 such patients in a tertiary care hospital in India. Two patients presented with obstructive jaundice and the third with pain abdomen. They had resectable lesions involving the pancreatic head, the right hepatic duct, and gallbladder fundus, respectively, on imaging. Tumor markers were not significantly elevated in any of them. All 3 patients underwent radical surgeries, suspecting malignancy. Surgical specimens showed typical features of IgG4-RD on histomorphology. Serum IgG4 level was elevated in first 2 patients but was normal in sclerosing cholecystitis patient. To conclude, IgG4-RD is a malignant mimicker; hence, on clinical suspicion, liberal attempts for tissue diagnosis may avoid radical surgeries.

TVNViewer: an interactive visualization tool for exploring networks that change over time or space.

UNLABELLED: The relationship between genes and proteins is a dynamic relationship that changes across time and differs in different cells. The study of these differences can reveal various insights into biological processes and disease progression, especially with the aid of proper tools for network visualization. Toward this purpose, we have developed TVNViewer, a novel visualization tool, which is specifically designed to aid in the exploration and analysis of dynamic networks. AVAILABILITY: TVNViewer is freely available with documentation and tutorials on the web at http://sailing.cs.cmu.edu/tvnviewer. CONTACT: epxing@cs.cmu.edu.

Enhancing the usability and performance of structured association mapping algorithms using automation, parallelization, and visualization in the GenAMap software system.

BACKGROUND: Structured association mapping is proving to be a powerful strategy to find genetic polymorphisms associated with disease. However, these algorithms are often distributed as command line implementations that require expertise and effort to customize and put into practice. Because of the difficulty required to use these cutting-edge techniques, geneticists often revert to simpler, less powerful methods. RESULTS: To make structured association mapping more accessible to geneticists, we have developed an automatic processing system called Auto-SAM. Auto-SAM enables geneticists to run structured association mapping algorithms automatically, using parallelization. Auto-SAM includes algorithms to discover gene-networks and find population structure. Auto-SAM can also run popular association mapping algorithms, in addition to five structured association mapping algorithms. CONCLUSIONS: Auto-SAM is available through GenAMap, a front-end desktop visualization tool. GenAMap and Auto-SAM are implemented in JAVA; binaries for GenAMap can be downloaded from http://sailing.cs.cmu.edu/genamap.

Colon perforation during percutaneous renal surgery: a 10-year experience in a single endourology centre.

The use of percutaneous renal surgery has been recently revolutionised with novel endourological instruments and techniques. However, the incidence, prevention and management of severe complications such as colon perforation still lack consensus. By presenting our 10-year experience, we would like to highlight the diagnosis and management of the rare complication of colon perforation.

Tenofovir-induced distal renal tubular acidosis: A rare cause of recurrent hypokalaemic paralysis.

Tenofovir disoproxil fumarate was the first nucleotide analogue reverse transcriptase inhibitor to be approved for treatment of human immunodeficiency virus infection. It is a relatively safe drug but can present with nephrotoxicity. We report a case of 36-year-old male who presented with acute onset flaccid paraparesis. He was a diagnosed case of acquired immunodeficiency syndrome for 9 years ago and was on tenofovir-based antiretroviral therapy for last 6 months. As the patient had normal anion gap metabolic acidosis, hypokalaemia and urine pH > 5.5, distal renal tubular acidosis (RTA) was suspected. He improved dramatically within 24 h of hospitalisation after potassium correction to regain normal power. Tenofovir-induced distal RTA presenting as hypokalaemic paralysis is a very rare complication of tenofovir; hence, we are reporting this case. In addition, we suggest regular follow-up of patients taking tenofovir with urine analysis and serum potassium to detect this complication earlier as it is reversible.

Correction: The importance of phase equilibrium for doping efficiency: iodine doped PbTe.

Correction for 'The importance of phase equilibrium for doping efficiency: iodine doped PbTe' by James Male et al., Mater. Horiz., 2019, 6, 1444-1453, DOI: 10.1039/C9MH00294D.

Primary Definitive Treatment versus Ureteric Stenting in the Management of Acute Ureteric Colic: A Cost-Effectiveness Analysis.

Objectives: To analyze the differences in cost-effectiveness between primary ureteroscopy and ureteric stenting in patients with ureteric calculi in the emergency setting. Patients and Methods: Patients requiring emergency intervention for a ureteric calculus at a tertiary centre were analysed between January and December 2019. The total secondary care cost included the cost of the procedure, inpatient hospital bed days, emergency department (A&E) reattendances, ancillary procedures and any secondary definitive procedure. Results: A total of 244 patients were included. Patients underwent ureteric stenting (62.3%) or primary treatment (37.7%), including primary ureteroscopy (URS) (34%) and shock wave lithotripsy (SWL) (3.6%). The total secondary care cost was more significant in the ureteric stenting group (GBP 4485.42 vs. GBP 3536.83; p = 0.65), though not statistically significant. While mean procedural costs for primary treatment were significantly higher (GBP 2605.27 vs. GBP 1729.00; p < 0.001), costs in addition to the procedure itself were significantly lower (GBP 931.57 vs. GBP 2742.35; p < 0.001) for primary treatment compared to ureteric stenting. Those undergoing ureteric stenting had a significantly higher A&E reattendance rate compared with primary treatment (25.7% vs. 10.9%, p = 0.02) and a significantly greater cost per patient related to revisits to A&E (GBP 61.05 vs. GBP 20.87; p < 0.001). Conclusion: Primary definitive treatment for patients with acute ureteric colic, although associated with higher procedural costs than ureteric stenting, infers a significant reduction in additional expenses, notably related to fewer A&E attendances. This is particularly relevant in the COVID-19 era, where it is crucial to avoid unnecessary attendances to A&E and reduce the backlog of delayed definitive procedures. Primary treatment should be considered concordance with clinical judgement and factors such as patient preference, equipment availability and operator experience.

Emergency Primary Ureteroscopy for Acute Ureteric Colic-From Guidelines to Practice.

OBJECTIVE: To review the factors that may influence the ability to achieve the present guidelines' recommendations in a well-resourced tertiary centre. According to current National Institute for Health and Care Excellence (NICE) guidelines, definitive treatment (primary ureteroscopy (URS) or shock wave lithotripsy (ESWL)) should be offered to patients with symptomatic renal colic that are unlikely to pass the stone within 48 h of diagnosis. METHODS: Retrospective review of all patients presenting to the emergency department between January and December 2019 with a ureteric or renal stone diagnosis. The rate of emergency intervention, risk factors for intervention and outcomes were compared between patients who were treated by primary definitive surgery vs. primary symptom relief by urethral stenting alone. RESULTS: A total of 244 patients required surgical management for symptomatic ureteric colic without symptoms of urinary infection. Of those, 92 patients (37.7%) underwent definitive treatment by either primary URS (82 patients) or ESWL (9 patients). The mean time for the procedure was 25.5 h (range: 1-118). Patients who underwent primary definitive treatment were likelier to have smaller and distally located stones than the primary stenting group. Primary ureteroscopy was more likely to be performed in a supervised setting than emergency stenting. CONCLUSIONS: Although definitive treatment carries high success rates, in a high-volume tertiary referral centre, it may not be feasible to offer it to all patients, with emergency stenting providing a safe and quick interim measure. Factors determining the ability to provide definitive treatment are stone location, stone size and resident supervision in theatre.

Factors Predicting Outcomes of Supine Percutaneous Nephrolithotomy: Large Single-Centre Experience.

Objective: Percutaneous nephrolithotomy (PCNL) is the treatment of choice for large renal calculi. The prone position has been considered the preferred position to obtain renal access. However, the supine position has recently gained popularity, which confers several potential advantages. The current study analyses the prognostic factors for successful supine PCNL procedures in a larger tertiary centre. Subjects: Prospective data were collected from all patients undergoing PCNL in the Galdako modified Valdivia position at our institution between February-2007 and September-2020. Surgical outcomes variables collected included: the rate of Endoscopic-combined intra-renal surgery (ECIRS), operative times, surgical effectiveness (no residuals <2 mm stone fragments) and complications. Results: A total of 592 patients underwent PCNL with a median age of 56 years (IQR: 42−67). The median stone size was 17 mm (IQR: 13−23). Of those, 79% of patients had an effective procedure. Stone size (p < 0.001), location (p < 0.001) and Guys-Stone Score (GSS) (p < 0.001) were associated with effectiveness. A Percutaneous nephrostomy tube was sited at the completion of the procedure in 97.3% of patients and a simultaneous double-J stent in 45.3%. Stent insertion was associated with larger stones (p < 0.001), the performance of ECIRS (p < 0.001) and higher GSS (p < 0.001). The overall complication rate was 21.7%. The main type of complication was an infection in 26.2 of the cases followed by the need for repeated nephrostogram in 12.7%. Conclusions: We demonstrate that PCNL in a high-volume centre is safe and efficacious in the Galdalko modified Valdivia position. Patients with smaller stones in the renal pelvis and a low GSS have the highest chance of a successful procedure.

Uncommon complication of feeding jejunostomy: A case report.

Feeding jejunostomy is a common surgical procedure performed for patients who cannot take oral feeds. Although a minor procedure, it is not without complications. However, distal migration of the tube into the bowel is extremely rare. A 50-year-old woman with corrosive stricture of the esophagus because of feeding jejunostomy feeds presented with internal dislodgement of the feeding tube. Abdominal X-ray and ultrasonogram could not locate the tube. On computed tomography, the feeding tube was found in the descending colon. She was managed conservatively, and the tube was expelled after three days. Internal dislodgement of tube usually does not produce any symptom. Computed tomography (CT) scan is diagnostic.

The importance of phase equilibrium for doping efficiency: iodine doped PbTe.

Semiconductor engineering relies heavily on doping efficiency and dopability. Low doping efficiency may cause low mobility and failure to reach target carrier concentrations or even the desired carrier type. Semiconducting thermoelectric materials perform best with degenerate carrier concentrations, meaning high performance in new materials might not be realized experimentally without a route to optimal doping. Doping in the classic PbTe thermoelectric system has been largely successful but reported doping efficiencies can vary, raising concerns about reproducibility. Here, we stress the importance of phase equilibria considerations during synthesis to avoid undesired intrinsic defects leading to sub-optimal doping. By saturation annealing at 973 K, we decidedly fix the composition in single crystal iodine-doped PbTe samples to be Pb-rich or Te-rich without introducing impurity phases. We show that, regardless of iodine concentration, degenerate n-type carrier concentrations with ideal doping efficiency require Pb-rich compositions. Electrons in Te-rich samples are heavily compensated by charged intrinsic Pb vacancy defects. From Hall effect measurements and a simple defect model supported by modern defect calculations, we map out the 973 K ternary Pb-Te-I phase diagram to explicitly link carrier concentration and composition. Furthermore, we discuss unintentional composition changes due to loss of volatile Te during synthesis and measurements. The methods and concepts applied here may guide doping studies on other lead chalcogenide systems as well as any doped, complex semiconductor.

Seminal thrombin-activatable fibrinolysis inhibitor: a regulator of liquefaction.

Several active components of the haemostatic system have been identified in human semen. Here we investigated the presence of thrombin-activatable fibrinolysis inhibitor (TAFI) in seminal plasma. Using an enzyme-linked immunosorbent assay, TAFI levels were measured in 36 semen specimens obtained from subfertile, normally fertile, fertile sperm donor and vasectomized individuals. TAFI was detectable in human semen. Its levels were highest in vasectomized individuals compared with the other groups, including a pooled normal semen parameter stratification group (by World Health Organization criteria). This elevation in the vasectomy group was found to be statistically significant in comparison with the normally fertile (P < 0.01) and the pooled normal semen parameter groups (P < 0.05). Seminal TAFI levels showed a significant positive correlation with total sperm count and sperm density. In contrast, a negative association was observed with semen volume, days of sexual abstinence and liquefaction time. The highly motile sperm group showed low TAFI levels. Our results establish the presence of TAFI in seminal plasma with a probable role in the protection of the seminal clot against lysis. It also suggests a downstream (post-testicular) source for its production. This reinforces the involvement of the conventional haemostatic system in the coagulation and liquefaction properties of human semen.

Supine Percutaneous Nephrolithotomy in the Galdako-Modified Valdivia Position: A High-Volume Single Center Experience.

OBJECTIVE: To describe the technique and outcomes of supine percutaneous nephrolithotomy (PCNL) in the Galdako-modified Valdivia position. MATERIALS AND METHODS: Prospective data were collected from 303 patients undergoing PCNL in the Galdako-modified Valdivia position at our institution between 2007 and 2015. We report our technique with outcomes of operative times, stone-free rate (SFR), and complications. RESULTS: A total of 202 solitary stones with a mean size of 17.19 ± 5.82 mm, 42 stones in multiple calices, and 57 staghorns were treated. Mean operative time was 79.79 ± 35.72 minutes. A total of 244/303 (80.5%) patients had clearance or <2 mm stone on postoperative CT. Minor complications (Clavien-Dindo Classification [CDC] 1-2) occurred in 59 (19.5%) cases and major complications (CDC ≥3) occurred in 22 (7.3%) cases. Five (1.7%) cases required postoperative blood transfusion for bleeding complications. CONCLUSION: We demonstrate that PCNL in a high-volume center to be safe and efficacious in the Galdalko-modified Valdivia position. We show equivalent SFR and complication rates to large studies of prone PCNL, with potential to decrease operative time. In particular, supine position is optimum for obese or high-risk patients with complex stone disease, because of ease of positioning and lower theoretical risk of anesthetic complications.

Multimarker risk stratification approach and cardiovascular outcomes in patients with stable coronary artery disease undergoing elective percutaneous coronary intervention.

AIMS: We studied the utility of multimarker risk stratification approach to predict cardiovascular outcomes in patients with stable coronary artery disease, undergoing elective percutaneous coronary intervention (PCI). METHODS: We prospectively evaluated 302 consecutive patients with stable coronary artery disease and normal CPK-MB and cardiac troponin T levels, and who underwent elective PCI at our institution. The following cardiac biomarkers were measured before and between 12 and 24h post-procedure: CK-MB, cardiac troponin T, hs-CRP, and NT-ProBNP. Patients were followed up for a minimum of 6 months. RESULTS: Post-PCI, CPK-MB levels were elevated but below myocardial infarction (MI) range in 70 patients (23%), and in the MI range in 6 patients (2%). Troponin T levels were detectable but below the 99th percentile (microleak) in 32 patients (10.6%) and elevated above the 99th percentile (periprocedural MI) in 104 patients (34.4%). At 9 months' follow-up, 1% died, 2% had stable angina, 10.3% had non-fatal MI, and 87.7% remained asymptomatic. There was no significant difference in clinical events among groups stratified by elevation of one biomarker or multiple biomarkers. CONCLUSION: Single or multiple biomarker strategy in patients with normal baseline biomarkers failed to predict major cardiac events after PCI over medium-term follow-up.