Retrospective cohort study of 925 OAGB procedures. The UK MGB/OAGB collaborative group

BACKGROUND

Mini-One Anastomosis Gastric Bypass is a new operation that provides comparable outcomes to the common bariatric procedures. Revisional surgery is still needed after a number of MGB-OAGB procedures. The aim of this study is to report the causes and management of these revisions.

METHODS

From 2010 to 2018, 925 MGB-OAGB operations were performed at 7 bariatric units across the United Kingdom and included in this retrospective cohort study. The data was retrospectively collected and analysed. The primary end point was the identification of the causes and management of revisions. Follow up ranged from 6 months to 3 years.

RESULTS

Twenty-two patients [2.3%] required revisional surgery after MGB-OAGB. Five patients [0.5%] developed severe diarrhoea managed by shortening the bilio-pancreatic limb to 150 cm. Four patients [0.4%] developed afferent loop syndrome and bile reflux was reported in another 3 [0.3%] cases; all were managed by either conversion to Roux en Y Gastric Bypass or a Braun anastomosis. Postoperative bleeding was controlled laparoscopically in 3 patients [0.3%]. Liver decompensation that was reported in 2 patients [0.2%] was treated by shortening the BPL in one patient and a reversal to normal anatomy in another. The liver failure resolved in both patients. Other indications for revision included two gastro-jejunal stenosis [0.2%], one perforated ulcer [0.1%], one patient [0.1%] with excessive weight loss and one case [0.1%] of protein malnutrition. None of the 22 patients undergoing revisional surgery after MGB-OAGB died. Lost to follow up rate was 0.2%.

CONCLUSION

Complications requiring revisional surgery after MGB-OAGB are uncommon [2.3%] and the majority can be managed by bilio-pancreatic limb shortening, the addition of a Braun side-to-side anastomosis or conversion to RYGB. Bilio-pancreatic limb length of 200 cm or more resulted in serious complications of liver failure, protein malnutrition, excessive weight loss and diarrhoea.

Variation between hospitals in outcomes following cardiac surgery in the UK

INTRODUCTION

We examine the influence of variations in provision of cardiac surgery in the UK at hospital level on patient outcomes and also to assess whether there is an inequality of access and delivery of healthcare. Cardiothoracic surgery has pioneered the reporting of surgeon-specific outcomes, which other specialties have followed. We set out to identify factors other than the individual surgeon, which can affect outcomes and enable other surgical specialties to adopt a similar model.

MATERIALS AND METHODS

A retrospective analysis of prospectively collected data of patient and hospital level factors between 2013 and 2016 from 16 cardiac surgical units in the UK were analysed through the Society for Cardiothoracic Surgery of Great Britain and Ireland and the Royal College of Surgeons Research Collaborative. Patient demographic data, risks factors, postoperative complications and in-hospital mortality, as well as hospital-level factors such as number of beds and operating theatres, were collected. Correlation between outcome measures was assessed using Pearson's correlation coefficient. Associations between hospital-level factors and outcomes were assessed using univariable and multivariable regression models.

RESULTS

Of 50,871 patients (60.5% of UK caseload), 25% were older than 75 years and 29% were female. There was considerable variation between units in patient comorbidities, bed distribution and staffing. All hospitals had dedicated cardiothoracic intensive care beds and consultants. Median survival was 97.9% (range 96.3-98.6%). Postoperative complications included re-sternotomy for bleeding (median 4.8%; range 3.5-6.9%) and mediastinitis (0.4%; 0.1-1.0%), transient ischaemic attack/cerebrovascular accident (1.7%; range 0.3-3.0%), haemofiltration (3.7%; range 0.8-6.8%), intra-aortic balloon pump use (3.3%; range 0.4-7.4%), tracheostomy (1.6%; range 1.3-2.6%) and laparotomy (0.3%; range 0.2-0.6%). There was variation in outcomes between hospitals. Univariable analysis showed a small number of positive associations between hospital-level factors and outcomes but none remained significant in multivariable models.

CONCLUSIONS

Variations among hospital level factors exists in both delivery of, and outcomes, following cardiac surgery in the UK. However, there was no clear association between these factors and patient outcomes. This negative finding could be explained by differences in outcome definition, differences in risk factors between centres that are not captured by standard risk stratification scores or individual surgeon/team performance.

The evolution and understanding of skeletal complication endpoints in clinical trials of tumors with metastasis to the bone

Bone metastases are a frequent complication of solid tumors, leading to significant skeletal sequelae that negatively impact quality of life and survival. Prevention and management of skeletal-related complications are critical treatment goals in oncology. Endpoints used in clinical trials to evaluate skeletal-related complications have evolved. In contrast to single measures of bone health, contemporary clinical trial endpoints reflect composite measures of skeletal-related complications, and increasingly also survival. In addition, key symptomatic components, which are more reflective of quality of life and the patient experience, are being incorporated. Given the evolution and resulting diversity of the endpoints being used in pivotal trials, it is becoming increasingly relevant to clarify the utility and the potential clinical impact of these measures not only within the context of trials but also in the real-world setting. Here, we describe the development and evolution of skeletal endpoints used in trials, and discuss their clinical relevance.

Systematic case finding for tuberculosis in HIV-infected people who inject drugs: experience from Pakistan

SETTING

Pakistan is a high tuberculosis (TB) burden country, moving from low human immunodeficiency virus (HIV) prevalence to a concentrated epidemic driven primarily by people who inject drugs (PWID). The Antiretroviral Treatment Adherence Unit (AAU) in Islamabad, Pakistan, is a residential facility that offers combined treatment for opioid dependence and HIV.

OBJECTIVE AND DESIGN

This retrospective study was conducted to assess TB prevalence among HIV-infected PWID referred to the AAU and to evaluate the diagnostic value of cough as a screening symptom. A single sputum sample was collected regardless of symptoms, and examined using smear, Xpert® MTB/RIF and culture.

RESULTS

Of 888 PWID, 71.5% submitted a sputum sample. More TB cases were detected using Xpert (n = 25) than with smear (n = 10) or culture (n = 20). A TB prevalence of 6141 per 100 000 was estimated based on seven cases already identified as being on anti-tuberculosis treatment and 32 newly diagnosed bacteriologically confirmed TB cases. Both cough and smoking (10 pack-years) were associated with increased TB prevalence. Only half of the TB cases reported cough. Rifampicin resistance was reported among 10% (3/29) of newly identified cases.

CONCLUSION

TB prevalence in HIV-infected PWID was 15 times higher than in the general adult population. As a screening symptom, cough has low diagnostic value.

Mesophilic, thermophilic and hyperthermophilic acidogenic fermentation of food waste in batch: Effect of inoculum source

Distinctions in hydrolysis and acidogenesis were examined for a series of anaerobic batch reactors inoculated with three different anaerobic mixed cultures (mesophilic, thermophilic and hyperthermophilic anaerobic sludge) and operated at the temperature of inoculum's origin and additionally at 70 °C. Hyperthermophilic temperatures led to increased hydrolysis rates during the start-up stage but a rapid drop in pH limited the overall hydrolysis efficiency, indicating the importance of pH control to sustain the high reaction rates at higher temperatures. No significant difference (P > 0.05) was observed among hydrolysis efficiencies obtained for different reactors which ranged between 27 ± 3% and 40 ± 14%. The highest fermentation yield of 0.44 g COD of fermentation products/g VSS-COD_added was obtained under thermophilic conditions, followed by mesophilic (0.33 g COD ferm. prod./g VSS-COD_added) and hyperthermophilic conditions (0.05-0.08 g COD ferm. prod./g VSS-COD_added). Fermentative performance was better at mesophilic and thermophilic conditions as indicated by improved production of volatile fatty acids (VFA). VFAs accounted for 60-71% of the solubilised matter at thermophilic and mesophilic conditions. Acetic acid formed the primary VFA (70%) at mesophilic temperatures, while butyric acid was the major VFA at thermophilic (60%) conditions. Hyperthermophilic conditions led to increased production of lactic acid, which comprised up to 32% of the solubilised matter. Overall, the results indicate that different operating temperatures may not significantly affect the substrate degradation efficiency but clearly influence the biotransformation pathways.

Peroxynitrite: cellular pathology and implications in autoimmunity

In inflamed tissues, the reaction of nitric oxide and superoxide leads to the formation of an extremely reactive peroxynitrite (ONOO-), which is a well known oxidizing and nitrating agent that exhibits high reactivity at physiological pH. The peroxynitrite formed can attack a wide range of biomolecules via direct oxidative reactions or indirect radical-mediated mechanisms thus triggering cellular responses leading to cell signaling, oxidative injury, committing cells to necrosis or apoptosis. Cellular DNA is an important target for ONOO- attack, and can react with deoxyribose, nucleobases or induces single strand breaks. The free radical-mediated damage to proteins results in the modification of amino acid residues, cross-linking of side chains and fragmentation. Free/protein-bound tyrosines are attacked by various reactive nitrogen species (RNS), including peroxynitrite, to form free/protein-bound nitrotyrosine (NT). The formation of NT represents a specific peroxynitrite-mediated protein modification, and the detection of NT in proteins is considered as a biomarker for endogenous peroxynitrite activity. The peroxynitrite-driven oxidation and nitration of biomolecules may lead to autoimmunity and age-related neurodegenerative diseases. Hence, peroxynitrite modified DNA and nitrated proteins can act as neoantigens and lead to the generation of autoantibodies against self-components in autoimmune disorders.

Influence of Patient Choice on Outcome of Bariatric Surgery

BACKGROUND

The "perfect" bariatric procedure remains the topic of debate. The aim of this study is to compare the safety and outcome of laparoscopic Roux-en-Y gastric bypass (LRYGB) to those of laparoscopic sleeve gastrectomy (LSG) and adjustable gastric band (AGB) in a single centre, amongst those patients who made their own choice of which procedure they prefer.

METHODS

After the multi-disciplinary team's assessment, the patients could make their own choice of procedures (self-selected, SS), unless medical/surgical conditions limited this (medically restricted, MR). All consecutive primary bariatric procedures were involved and reviewed between June 2010 and September 2014. The primary outcomes included 30-day complication and readmission rates, excess weight loss (%EWL) and co-morbidity resolution at 24 months postoperatively.

RESULTS

A total of 303 patients were included and 271 of them made their own choice (SS 90%). One hundred eighty-three chose LRYGB (60.4%), and 57 underwent LSG (SS 45 and MR 12; overall 18.8%), with the initial BMI of 50.7 and 52.5 kg/m², respectively. Sixty-two patients (SS 43, MR 19, overall 20%) underwent AGB, with a BMI of 52.1 kg/m². Thirty-day complication rates for LRYGB and LSG were 10.2 and 2.9% (p < 0.05), and the readmission rates were 4.7 and 2.9%, respectively. %EWL for LRYGB was significantly higher than that of other procedures at 24 months (67.8 vs SS-sleeve 43.9%, MR-sleeve 47%, SS-band 33.8% and MR-band 36%; FU rate 94%). Diabetes remission was achieved in 31/50 patients in the LRYGB group (62%) and 2/9 patients (22%) in the LSG group.

CONCLUSIONS

Self-selected bariatric procedures yield excellent weight loss and metabolic outcome. Providing an information-dense environment augments the choice of the right operation and could improve patients' compliance with weight loss surgery programmes.

Enhancement of fluorescence emission difference microscopy using conjugated vortex phase modulation

In this paper, we propose and demonstrate an improved fluorescence emission difference microscopy (FED) method, exploiting programmable phase modulation for image enhancement. The main novelty of the proposed approach lies in the matched size and intensity of two excitation spots. The proposed method improves the FED performance on image quality via artefact elimination. We demonstrate the feasibility of this method through theoretical studies and experimental tests. The experimental results of nanobeads and cells validate the practical performance of this method, which can enable reliable observations at superresolution in biomedical studies. LAY DESCRIPTION: In this paper, we propose a method to improve the imaging quality of regular fluorescence emission difference (FED) microscopy. In regular FED imaging, a solid and a doughnut excitation beam are successively used to acquire two images which are then subtracted with each other to improve the resolution of confocal microscopy. The doughnut beam can be generated by modulating the excitation beam with a vortex phase mask. Note that both of the excitation beam and the vortex phase mask must have the same handed direction in regular FED microscopy. However, some negative values may be produced and some information may be lost due to the subtraction process in regular FED imaging, which is mainly caused by the mismatched size and intensity of these two excitation spots. To address this issue, we propose conjugated FED (cFED) microscopy which additionally uses a conjugated vortex phase mask to modulate the solid beam to extend its focal spot size to be matched with the doughnut spot, which means the handed direction of the solid beam and the vortex phase mask is different. Besides, in order not to damage the resolution, the doughnut beam needs to be saturated to some degree. The experiment results show that, at the same resolution level, the negative values and the information loss in cFED image are all less than that of regular FED image.

A plea for an early ultrasound-clinical integrated approach in patients with acute heart failure. A proactive comment on the ESC Guidelines on Heart Failure 2016

BACKGROUND

The European Association of Cardiology (ESC) Guidelines on the diagnosis and treatment of acute heart failure (AHF) indicate prompt therapy initiation and performance of relevant investigations as paramount. Specifically, echocardiography prior to treatment is advocated only with hemodynamic instability, and the evaluation of clinical signs of peripheral perfusion and congestion is suggested as guidance for early interventions. Given the growing body of evidence on the diagnostic/monitoring capabilities of bedside ultrasound (including focused cardiac ultrasound, comprehensive echocardiography, lung ultrasound), we discuss the potential benefit of an integrated clinical/ultrasound approach at the very early stages of acute heart failure.

METHODS AND RESULTS

We proposed a narrative review of the current evidence on the clinical-ultrasound integrated approach to AHF, with special emphasis on the components of the early diagnostic-therapeutic workup where cardiac, inferior vena cava and lung ultrasound showed high diagnostic accuracy and the capability of substantially changing an exclusively clinically-oriented patient management. A proactive comment to the ESC guidelines is made, suggesting an integration of clinical and biochemical assessment, as defined by guidelines, with combined bedside ultrasound on may help in the definition of AHF pathophysiology and treatment.

CONCLUSION

A multi-organ integrated clinical-ultrasound approach should be advocated as part of the clinical-diagnostic workup at AHF very early phase. Whenever competence and technology available, bedside ultrasound, along with clinical and biochemical assessment, should target AHF profiling, identify the cause of AHF, and subsequently aid disease course and response to treatment monitoring.

Curriculum content and assessment of pre-clinical dental skills: A survey of undergraduate dental education in Europe

INTRODUCTION

Since 1981, the qualifications for various healthcare professionals across the European Union have enjoyed mutual recognition in accordance with the EU Directive 81/1057/EEC. Whilst the directive includes dental practitioners, it is recognised that significant variation exists in curriculum structure, content and scope of practice across institutions. This article aimed to explore pan-European practice in relation to curriculum content, teaching and learning strategies and assessment of pre-clinical dental skills.

METHOD

A request to complete an online questionnaire, in English, was sent electronically to skills leads at all Association of Dental Education in Europe member schools. The questionnaire collected information in relation to institution and country, regulatory requirements to demonstrate safety, details of specific pre-clinical skills courses, learning materials and teaching staff.

RESULTS

Forty-eight institutions, from 25 European countries responded. Seven countries (n=7, 28%) reported no requirement to demonstrate student operative safety prior to patient treatment. Several core and operative clinical skills are common to the majority of institutions. The most commonly taught core skills related directly to the clinical environment such as cross-infection control and hand washing. The least common were skills that indirectly related to patient care, such as communication skills and working as a team.

CONCLUSION

There are clear differences within European pre-clinical dental education, and greater efforts are needed to demonstrate that all European students are fit to practice before they start treating patients. Learning outcomes, teaching activities and assessment activities of pre-clinical skills should be shared collaboratively to further standardise curricula.

Cell wall microstructure, pore size distribution and absolute density of hemp shiv

This paper, for the first time, fully characterizes the intrinsic physical parameters of hemp shiv including cell wall microstructure, pore size distribution and absolute density. Scanning electron microscopy revealed microstructural features similar to hardwoods. Confocal microscopy revealed three major layers in the cell wall: middle lamella, primary cell wall and secondary cell wall. Computed tomography improved the visualization of pore shape and pore connectivity in three dimensions. Mercury intrusion porosimetry (MIP) showed that the average accessible porosity was 76.67 ± 2.03% and pore size classes could be distinguished into micropores (3-10 nm) and macropores (0.1-1 µm and 20-80 µm). The absolute density was evaluated by helium pycnometry, MIP and Archimedes' methods. The results show that these methods can lead to misinterpretation of absolute density. The MIP method showed a realistic absolute density (1.45 g cm^-3) consistent with the density of the known constituents, including lignin, cellulose and hemi-cellulose. However, helium pycnometry and Archimedes' methods gave falsely low values owing to 10% of the volume being inaccessible pores, which require sample pretreatment in order to be filled by liquid or gas. This indicates that the determination of the cell wall density is strongly dependent on sample geometry and preparation.

Capacitated vehicle-routing problem model for scheduled solid waste collection and route optimization using PSO algorithm

Waste collection widely depends on the route optimization problem that involves a large amount of expenditure in terms of capital, labor, and variable operational costs. Thus, the more waste collection route is optimized, the more reduction in different costs and environmental effect will be. This study proposes a modified particle swarm optimization (PSO) algorithm in a capacitated vehicle-routing problem (CVRP) model to determine the best waste collection and route optimization solutions. In this study, threshold waste level (TWL) and scheduling concepts are applied in the PSO-based CVRP model under different datasets. The obtained results from different datasets show that the proposed algorithmic CVRP model provides the best waste collection and route optimization in terms of travel distance, total waste, waste collection efficiency, and tightness at 70-75% of TWL. The obtained results for 1 week scheduling show that 70% of TWL performs better than all node consideration in terms of collected waste, distance, tightness, efficiency, fuel consumption, and cost. The proposed optimized model can serve as a valuable tool for waste collection and route optimization toward reducing socioeconomic and environmental impacts.

Toxicity and Detoxification Mechanism of Black Pepper and Its Major Constituent in Controlling Rhynchophorus ferrugineus Olivier (Curculionidae: Coleoptera)

The survival, feeding response, and detoxification mechanism of Rhynchophorus ferrugineus Olivier, a key pest responsible for destruction of date palm, was examined with different extracts of Piper nigrum and its major constituent (piperine) identified by GC-MS. In the present study, toxicity of different extracts of black pepper was evaluated by incorporating diffferent doses of extracts into the artificial diet of red palm weevil larvae. All extracts showed dose-dependent insecticidal activity to the tested eighth-instar red palm weevil larvae. Among all the extracts, maximum larvicidal activity was exhibited by chloroform (LD₅₀ = 342.62 mg/l), followed by dichloromethane (LD₅₀ = 357.78 mg/l), acetone (LD₅₀ = 372.57 mg/l), and ethanol (LD₅₀ = 408.88 mg/l). However, piperine, a major constituent of all black pepper extracts identified by GC-MS in the present work, was found to be the most potent treatment exhibiting the least LD₅₀ (219.88 mg/l). In addition, nutritional indices evaluated by calculating the efficiency of the conversion of ingested food (ECI) and digested food (ECD) at the same dose (219.88 mg/l) showed that there was maximum reduction in the ECI (49.90%) and ECD (62.21%) index of larvae fed diets incorporated with piperine. Larvae that were fed diets incorporated with different black pepper extracts experienced increases in the expression of detoxification genes (glutathione S-transferase and cytochrome P450), and this upregulation in detoxification genes (glutathione S-transferase, cytochrome P450 and esterase) was tremendously high in larvae fed diets incorporated with piperine. Results suggest that piperine is a promising bio-pesticide agent for the control of R. ferrugineus Olivier.

Blue light-induced immunosuppression in Bactrocera dorsalis adults, as a carryover effect of larval exposure

Detrimental effects of ultraviolet (UV) light on living organisms are well understood, little is known about the effects of blue light irradiation. Although a recent study revealed that blue light caused more harmful effects on insects than UV light and blue light irradiation killed insect pests of various orders including Diptera, the effects of blue light on physiology of insects are still largely unknown. Here we studied the effects of blue light irradiation on cuticular melanin in larval and the immune response in adult stage of Bactrocera dorsalis. We also evaluated the effects of blue light exposure in larval stage on various age and mass at metamorphosis and the mediatory role of cuticular melanin in carryover effects of larval stressors across metamorphosis. We found that larvae exposed to blue light decreased melanin contents in their exoskeleton with smaller mass and delayed metamorphosis than insects reared without blue light exposure. Across metamorphosis, lower melanotic encapsulation response and higher susceptibility to Beauveria bassiana was detected in adults that had been exposed to blue light at their larval stage, thereby constituting the first evidence that blue light impaired adult immune function in B. dorsalis as a carryover effect of larval exposure.