bluuebunny/crossref_metadata_2025 huggingface dataset:
Melting curve analysis to differentiate Rickettsia spp. and Rickettsia felis
Authors: Widiastuti D , Agustiningsih  , Wijayati S P M , Lestari E
Published: December 2021

Rickettsiosis, caused by Rickettsia species, is one of the old arthropod-borne illness that commonly found in humans and animals. One of the barriers to rickettsiosis control is the intricacy and time-consuming nature of rickettsiosis laboratory diagnosis. This study aimed to establish quantitative real-time PCR targeting the gltA gene for the DNA differentiation of Rickettsia spp. and Ricketsia felis. The collection of cat flea was extracted to acquire the DNA of Rickettsia. Primers were designed based on the analysis of Rickettsia gltA gene sequences. The confirmation of R. felis was performed by sequencing of PCR product. BLAST analysis was done to confirm the closest similarity of the sequences. Results of this study highlighted the melting temperature was reached at 78,5 °C for Rickettsia spp. and 76.5+0.5 °C for Rickettsia felis. The melting peak temperatures were significantly different between Rickettsia spp. and R. felis (p<0.05). The findings of this work are crucial in the development of powerful diagnostic procedures for detecting and distinguishing Rickettsia spp. and R. felis species.
Transformation and characterization of human insulin precursor gene in Pichiapastoris X-33
Authors: Sekaringtyas F C , Hardianto D , Karimah N , Nida V , Zahra A
Published: December 2021

The case of diabetes increases significantly and has been projected to reach 592 million people in 2035. Consequently, the necessity of insulin will rise manifold and an efficient production system for insulin production is required to meet the market demands. The human insulin precursors that enzymatically converted to human insulin can be produced usingEscherichia coli, Saccharomyces cerevisiae, orPichia pastoris. In this study,Pichia pastorisis used for production human insulin precursor because the resulting recombinant protein can be folded accordingly and secreted to the external environment of the cell that simplifies the purification process. The study was initiated with the insertion of a synthetic gene of human insulin precursor into the pPICZaA to create recombinant pPICZaA-IP plasmid. The recombinant plasmid was transformed intoEscherichia coliTop10 which then isolated and digested by theSacIenzyme. The linearize pPICZaA-IP plasmid was transfected intoPichia pastorisX-33 by electroporator. The result of transformation process, a total of 20 colonies of PpastorisX-33 were selected and inoculated in YPD agar medium containing Zeocin. The two colonies of Ppastoriswere characterized by PCR and sequencing showed that the recombinant pPICZaA-IP plasmid was successfully integrated into selected colonies of Ppastoris.
Kaolin application to increase lettuce (Lactuca sativa) growth under suboptimal watering condition
Authors: Fawwaz H F , Lathifatunnisa S , Hemelda N M , Yuniati R
Published: December 2021

Lettuce is a crop sensitive to water availability as it needs more water in cultivation. Kaolin has been reported to reduce the impact of drought stress in plants. However, the use of kaolin to increase lettuce growth under drought condition has not been reported yet. In this study, the effect of kaolin to increase the growth of lettuce under suboptimal watering condition was investigated. Kaolin foliar application (3%, 5%, and 6%) was tested on a group consisting of 5 lettuce plants grown under reduced watering condition in a greenhouse. Lettuce height, number of leaves, root length, leaf length and width, fresh and dry weight of lettuce, and leaf chlorophyll content were observed. Kaolin applications significantly increased the growth of lettuce in most parameters compared to the negative control (reduced watering condition, without kaolin). Kaolin 3% application presented the best treatment to increase growth parameters. All kaolin applications did not affect chlorophyll content significantly under lower watering condition. In conclusion, kaolin was able to reduce the impact of reduced watering condition and increase lettuce growth but showed no effect on the leaf chlorophyll content. Thus, further evaluation of kaolin application in lettuce under drought condition is needed.
Synthesis of layered vs planar Mo2C: role of Mo diffusion
Authors: Shehzad M Arslan , Das Paul Masih , Tyner Alexander C , Cheng Matthew , Lee Yea-Shine , Goswami P , Dos Reis Roberto , Chen Xinqi , Dravid Vinayak P
Published: December 2021

Chemical vapor deposition growth of metal carbides is of great interest as this method provides large area growth of MXenes. This growth is mainly done using a melted diffusion based process; however, different morphologies in growth process is not well understood. In this work, we report deterministic synthesis of layered (non-uniform c-axis growth) and planar (uniform c-axis growth) of molybdenum carbide (Mo2C) using a diffusion-mediated growth. Mo-diffusion limited growth mechanism is proposed where the competition between Mo and C adatoms determines the morphology of grown crystals. Difference in thickness of catalyst at the edge and center lead to enhanced Mo diffusion which plays a vital role in determining the structure of Mo2C. The layered structures exhibit an expansion in the lattice confirmed by the presence of strain. Density functional theory shows consistent presence of strain which is dependent upon Mo diffusion during growth. This work demonstrates the importance of precise control of diffusion through the catalyst in determining the structure of Mo2C and contributes to broader understanding of metal diffusion in growth of MXenes.
Typical representations via fixed point sets in Bruhat–Tits buildings
Authors: Latham Peter , Nevins Monica
Published: December 2021

For a tame supercuspidal representation

π
\pi

of a connected reductive

p
p

-adic group

G
G

, we establish two distinct and complementary sufficient conditions, formulated in terms of the geometry of the Bruhat–Tits building of

G
G

, for the irreducible components of its restriction to a maximal compact subgroup to occur in a representation of

G
G

which is not inertially equivalent to

π
\pi

. The consequence is a set of broadly applicable tools for addressing the branching rules of

π
\pi

and the unicity of

[
G
,
π

]
G

[G,\pi ]_G

-types.
Alternative oxidase (AOX) in the carnivorous pitcher plants of the genus Nepenthes: what is it good for?
Authors: Pavlovič Andrej , Kocáb Ondřej
Published: December 2021

Background and Aims

The carnivorous pitcher plants of the genus Nepenthes have evolved modified leaves that act as pitcher traps. The traps are specialized for prey attraction, capture, digestion and nutrient uptake but not for photosynthetic assimilation.

Methods

In this study, we used antibodies against different photosynthetic (D1, Lhcb2, Lhcb4, RbcL) and respiratory-related (AOX, COXII) proteins for semi-quantification of these proteins in the assimilation part of the leaves and the pitcher traps of different Nepenthes species and hybrids. Different functional zones of the trap and the traps from different ontogenetic stages were investigated. The pitcher traps of the distantly related species Sarracenia purpurea ssp. venosa were used as an outgroup. In addition, chlorophyll fluorescence and infrared gas analysis were used for measurements of the net rate of photosynthesis (AN) and respiration in the dark (RD).

Key Results

The pitcher traps contained the same or lower abundance of photosynthesis-related proteins in accordance with their low AN in comparison to the assimilation part of the leaves. Surprisingly, all traps contained a high amount of alternative oxidase (AOX) and low amount of cytochrome c oxidase subunit II (COX II) than in the assimilation part of the leaves. Thermal imaging did not confirm the role of AOX in pitcher thermogenesis.

Conclusions

The pitcher traps contain a high amount of AOX enzyme. The possible role of AOX in specialized pitcher tissue is discussed based on knowledge of the role and function of AOX in non-carnivorous plants. The roles of AOX in prey attraction, balance between light and dark reactions of photosynthesis, homeostasis of reactive oxygen species, digestive physiology and nutrient assimilation are discussed.
Distinguishing carbon gains from photosynthesis and heterotrophy in C3-hemiparasite–C3-host pairs
Authors: Giesemann Philipp , Gebauer Gerhard
Published: December 2021

Background and Aims

Previous carbon stable isotope (13C) analyses have shown for very few C3-hemiparasites utilizing C4- or CAM-hosts the use of two carbon sources, autotrophy and heterotrophy. This 13C approach, however, failed for the frequently occurring C3–C3 parasite–host pairs. Thus, we used hydrogen stable isotope (2H) natural abundances as a substitute for 13C within a C3-Orobanchaceae sequence graded by haustoria complexity and C3-Santalaceae.

Methods

Parasitic plants and their real or potential host plants as references were collected in Central European lowland and alpine mountain meadows and forests. Parasitic plants included the xylem-feeding holoparasite Lathraea squamaria parasitizing on the same carbon nutrient source (xylem-transported organic carbon compounds) as potentially Pedicularis, Rhinanthus, Bartsia, Melampyrum and Euphrasia hemiparasites. Reference plants were used for an autotrophy-only isotope baseline. A multi-element stable isotope natural abundance approach was applied.

Key Results

Species-specific heterotrophic carbon gain ranging from 0 to 51 % was estimated by a 2H mixing-model. The sequence in heterotrophic carbon gain mostly met the morphological grading by haustoria complexity: Melampyrum- < Rhinanthus- < Pedicularis-type.

Conclusion

Due to higher transpiration and lower water-use efficiency, depletion in 13C, 18O and 2H compared to C3-host plants should be expected for tissues of C3-hemiparasites. However, 2H is counterbalanced by transpiration (2H-depletion) and heterotrophy (2H-enrichment). Progressive 2H-enrichment can be used as a proxy to evaluate carbon gains from hosts.
Mesopredators retain their fear of humans across a development gradient
Authors: Reilly Chloe M , Suraci Justin P , Smith Justine A , Wang Yiwei , Wilmers Christopher C
Published: December 2021

Anthropogenic impacts on wildlife behavior arise both from the immediate presence of people, which induces fear responses in many species, and the human footprint (i.e., landscape modification such as residential development), which affects animal movement and habitat use. Where both disturbance types co-occur, disentangling their impacts remains a challenge. Disturbance effects may interact such that species respond to increased human footprint by either reducing (habituation) or increasing (sensitization) avoidance of human presence. We experimentally manipulated perceived human presence, using playbacks of people talking, across a gradient of human footprint in California’s Santa Cruz Mountains and used camera traps to quantify the behavioral responses of bobcats (Lynx rufus), striped skunks (Mephitis mephitis), and Virginia opossums (Didelphis virginiana), mesopredators known to exhibit strong fear response to human presence but which vary in their use of developed areas. Bobcats and skunks reduced activity in response to human playbacks but showed no change in responsiveness to playbacks across the gradient of human footprint, suggesting that these species are similarly fearful of humans at all development levels tested. Opossums exhibited a significant interaction between human footprint and playback treatment such that reductions in activity level in response to human playbacks were strongest at higher levels of building density. Our results indicate that, rather than habituating to human presence, some mesopredators retain a strong fear of humans or become more fearful when inhabiting more developed areas. We suggest that consistently high responsiveness to immediate human presence may benefit mesopredators living in human-dominated landscapes by mitigating the risk of anthropogenic mortality.
Identification of alternative splicing-derived cancer neoantigens for mRNA vaccine development
Authors: Cheng Rui , Xu Zhaochun , Luo Meng , Wang Pingping , Cao Huimin , Jin Xiyun , Zhou Wenyang , Xiao Lixing , Jiang Qinghua
Published: December 2021

Messenger RNA (mRNA) vaccines have shown great potential for anti-tumor therapy due to the advantages in safety, efficacy and industrial production. However, it remains a challenge to identify suitable cancer neoantigens that can be targeted for mRNA vaccines. Abnormal alternative splicing occurs in a variety of tumors, which may result in the translation of abnormal transcripts into tumor-specific proteins. High-throughput technologies make it possible for systematic characterization of alternative splicing as a source of suitable target neoantigens for mRNA vaccine development. Here, we summarized difficulties and challenges for identifying alternative splicing-derived cancer neoantigens from RNA-seq data and proposed a conceptual framework for designing personalized mRNA vaccines based on alternative splicing-derived cancer neoantigens. In addition, several points were presented to spark further discussion toward improving the identification of alternative splicing-derived cancer neoantigens.
On the Dynamic Nature of Omnivory in a Changing World
Authors: Gutgesell Marie K , McCann Kevin S , Gellner Gabriel , Cazelles Kevin , Greyson-Gaito Christopher J , Bieg Carling , Guzzo Matthew M , Warne Connor P K , Ward Charlotte A , O'Connor Reilly F , Scott Alexa M , Graham Brandon C , Champagne Emily J , McMeans Bailey C
Published: December 2021

Nature's variability plays a major role in maintenance of biodiversity. As global change is altering variability, understanding how key food web structures maintain stability in the face of variation becomes critical. Surprisingly, little research has been undertaken to mechanistically understand how key food web structures are expected to operate in a noisy world and what this means for stability. Omnivory, for example, has been historically well studied but largely from a static perspective. Recent empirical evidence suggests that the strength of omnivory varies in response to changing conditions in ways that may be fundamental to stability. In the present article, we extend existing omnivory theory to predict how omnivory responds to variation and to show that dynamic omnivory responses are indeed a potent stabilizing structure in the face of variation. We end by synthesizing empirical examples within this framework, demonstrating the ubiquity of the theoretical mechanisms proposed across ecosystem types, spatial scales, and taxa.
O-B01 Role of Ursodeoxycholic acid in prevention of gallstones formation in bariatric patients: need to amend recent BOMSS guidelines
Authors: Sharma Amit , Nageswaran Hari , Saad Ahmed , Patel Ameet , Best Lawrence
Published: December 2021

Background

During rapid weight-loss phase following bariatric procedures, biliary cholesterol homeostasis is altered leading to increased propensity to gallstone formation. Incidence of gallstone formation following bariatric procedures is shown to be 10-38%. There is no consensus regarding its prevention and current BOMSS guidelines do not address this issue. This meta-analysis aims to pool high level evidence (RCTs) to assess efficacy of Ursodeoxycholic acid (UDCA) in reducing risk of gallstone formation in this cohort of patients and the need for revision of current guidelines.

Methods

A systematic literature search was performed using electronic databases (Medline, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, PROSPERO and Google Scholar) in line with PRISMA guidelines. Only randomised controlled trials were included without restrictions on study language, year, status of publication and patient’s age. Meta-analysis was performed using Review Manager Software to calculate pooled risk ratios (RR) using random-effects model.

Results

Fifteen trials were included (3952 patients analysed, 2487 in UDCA and 1465 in placebo group). The overall rate of gallstone formation was 16.0% (6.4% in UDCA vs 31.4% in placebo group). Trials included various bariatric procedures (SG/RYGB/OAGB/AGB/Gastroplasty). UDCA dose ranged from 300 to 1200mg per day. UDCA significantly reduced the risk of post-operative gallstone formation (3952 patients, RR 0.24, 95% CI 0.16-0.37, p < 0.0001). The absolute risk reduction and number needed to treat (NNT) were 25% and 4 respectively.

Conclusions

Oral Ursodeoxycholic acid treatment following restrictive bariatric surgical procedures significantly reduces the risks of gallstone formation. As such, its regular use in first 6 months (rapid weight-loss phase) can significantly reduce the risk of complications associated with gallstones. Such treatment would be cost effective and benefit 1 in 4 patients. There is significant evidence available on benefits of using UDCA in post-operative bariatric patients and that this should be added to the recent BOMSS guidelines.
O-BN04 Laparoscopic assisted robotic Heller’s cardiomyotomy in achalasia: a 12-year experience
Authors: Siriwardana Priyantha , Lorenzi Bruno , Qamruddin Mohammad , Kadirkamanathan Sritharan
Published: December 2021

Background

Heller’s cardiomyotomy (HC) using a computer-enhanced (robotic) laparoscopic platform allows for a more precise dissection. This is achieved by utilizing the superior optics of a 3D camera and greater degrees of freedom provided by robotic instrumentation. Our aim was to assess short to long term outcomes in terms of mucosal integrity, hospital stay and symptom improvement and quality of life.

Methods

A retrospective review of prospectively collected data was performed of patients who underwent robotic HC between July 2009- May 2021. HC was performed using a Da Vinci robot S and Xi (Intuitive Surgical Inc.) with 4 laparoscopic ports and liver retractor. Anterior mobilization of the oesophagus was performed leaving the posterior component of phreno-oesophageal ligament intact. A longitudinal myotomy was made extending into the proximal stomach. An anti-reflux procedure (ARP) was not routinely performed. Data collected including demography, Eckardt symptom score, Quality of Life (QoL) with SF-36, surgical technical data and surgical outcome (post-op morbidity, mortality, hospital stay).

Results

Fifty-seven patients underwent surgery (28 males). Median age was 46 years (18-71). Two had surgery for recurrent dysphagia following laparoscopic HC elsewhere. Median length of myotomy was 8cm (5-11). No mucosal breaches were identified at surgery, but one had postoperative leak. Median length of hospital stay was 2 days (1-148). One had chest infection and another DVT. Median follow-up was 61 months (2- 86). There was no mortality. Three patients (5%) needed oesophageal dilatation during follow-up. There was a significant improvement in Eckardt score from 10 (9-12) to 2 (0-6), and in all components of QoL (p < 0.05).

Conclusions

Heller’s myotomy can be performed very precisely using a Da Vinci Robot. It minimises the risk of mucosal breach reflecting in the low leak rate. No patient had developed troublesome reflux which may well be due to the preservation of the posterior component of the phreno-oesophageal ligament. It also improves symptoms and quality of life for many years. Robotic HC may become the standard treatment for achalasia in the very near future.
O-EGS06 Trials and Tribulations: Educational Impact and Recommendations from the Implementation of Student-Led Recruitment in a Clinical Trial
Authors: Cambridge William , Riad Aya , Henshall David , McAdam Heather , Glasbey James , Harrison Ewen , McLean Kenneth
Published: December 2021

Background

Medical students have an essential role in medical research, yet often feel unprepared and lack opportunities for involvement as recruiters within research studies. This study aimed to understand the educational effect of involvement in clinical trial recruitment on medical students, and to derive generalisable future recommendations.

Methods

Tracking wound infection with smartphone technology (TWIST) was a randomised controlled trial enrolling adult emergency abdominal surgery patients across two university teaching hospitals. All recruiters underwent pre-recruitment training based on “Generating Student Recruiters for Randomised Trials” (GRANULE) principles, and completed pre-and post-recruitment surveys. Respondent agreement with statements were assessed using 5-point Likert scales (from 1 [“strongly disagree”] to 5 [“strongly agree”]). Quantitative data were analysed using paired t-tests to compare differences pre- and post-involvement, and a thematic analysis approach adopted for anonymised free-text answers.

Results

Of 492 patients recruited to TWIST from 2016 to 2020, 86.0% (n = 423) were recruited by medical students. Following student involvement, the monthly recruitment rate tripled (4.8 to 15.7 patients). Thirty student recruiters (96.8%), completed both surveys, reporting significant improvements in clinical and academic competencies. This included increased confidence in gaining and documenting consent, as well as interest in pursuing a clinical-academic career. Over half (58.2%) felt the undergraduate curriculum had not prepared them for involvement in clinical trials (mean:2.47, SD: 0.94). There were three emergent themes regarding recommendations for involvement of students, based on their engagement, preparation, and support during recruitment.

Conclusions

Student recruitment in clinical trials is feasible and provides a route to developing a research-active medical workforce. It also accelerates recruitment to clinical trials, as well as benefiting students through development of clinical competencies and provision of additional exposure to research. Adequate training, support, and selection of suitable trials are essential for successful student engagement.
O-L04 Peri-operative thrombophilia in patients undergoing liver resection for colorectal metastases
Authors: Walsh Caoimhe , Welsh Fenella , Rathnaweera Wasula , Chandrakumaran Kandiah , Roy Ashok , Needham Jane , Cresswell Ben , McVey John , Rees Myrddin
Published: December 2021

Background

The risk of major haemorrhage during liver surgery has decreased considerably in the modern era. However, there remains reluctance amongst liver surgeons to give routine peri-operative chemical thromboprophylaxis, either because of the perceived risk of bleeding, or transient post-operative abnormalities in conventional coagulation studies. The aim of this study was to ask whether a defined, homogeneous population of patients undergoing liver resection for colorectal metastases (CRM) were at risk from venous thromboembolism (VTE) prior to surgery, and what the impact of liver resection was on that risk.

Methods

A single-centre prospective observational cohort study comparing pre-, peri- and post-operative haemostasis variables in patients undergoing liver resection for CRM. Patients with cirrhosis, history of VTE or anticoagulated were excluded, as were patients undergoing small wedge, or laparoscopic liver resections. Blood samples for coagulation assays were collected pre-operatively, peri-operatively (after transection) and first post-operative day (13–20 hours post-operatively). Pre- and post-operative Tissue Factor messenger ribonucleic acid (TFmRNA) activation was measured from peripheral blood mononuclear cells (PBMCs) using semi-quantitative polymerase chain reaction (PCR). Patients received peri-operative mechanical thromboprophylaxis until mobile, plus chemical thromboprophylaxis on the first post-operative day, after venesection.

Results

Of 336 hepatectomies performed October 2017-December 2019, 60 resections in 57 patients were recruited. This included 46.7% major resections, with median (interquartile range [IQR]) blood loss 150.0mls (76.3-263.7), no blood transfusions, post-operative VTE events or deaths. Patients were prothrombotic pre-operatively (high factor VIIIC and thrombin generation velocity index), an effect exacerbated post-hepatectomy. Major hepatectomies had a significantly greater drop in Protein C, rise in Factor VIIIC and von Willebrand Factor, versus minor resections (p = 0.001,0.005,0.001 respectively). Patients with transection times greater than median (40minutes), had significantly increased median (IQR) PMBC-TFmRNA expression [1.65 (0.93-2.70)2ddCt], versus quicker transections [0.99 (0.69-1.28)2ddCt, p = 0.020].

Conclusions

These data show the risk of major haemorrhage in elective liver resection in a high volume unit is low and administration of chemical thromboprophylaxis within 13-20 hours of surgery is safe and effective. The study demonstrates that patients with CRM are prothrombotic pre-operatively. Furthermore, this thrombophilia is exacerbated by liver resection, and most marked in patients with longer, more complex operations. These data suggest that chemical thromboprophylaxis should be considered earlier in the patient pathway, and has resulted in a change in practice for the authors.
P-B01 First Inventory of Access and Quality of Metabolic Surgery across Europe
Authors: Sinclair Piriyah , Vijgen Guy , Aarts Edo , Van Nieuwenhove Yves , Maleckas Almantas
Published: December 2021

Background

Europe consists of 51 independent countries. Variation in healthcare regulations results in differing challenges faced by patients and professionals. The obesity pandemic has multiple health, economic and social implications. However, metabolic surgery is not universally accessible, with significant variations in its provision. This study aimed to gain insight into compliance with international guidelines; the accessibility and barriers to surgery; patient pathways and qualitor indicators of both metabolic and body contouring surgery after weight loss in different European countries.

Methods

This study was initiated during the European Obesity Academy (EOA). Expert representatives in the metabolic field from all 51 European countries were sent a novel, 37-item, electronic self-administered online questionnaire on their data and experiences from the previous year exploring accessibility to and quality indicators for metabolic surgery and body contouring surgery after weight loss. The survey tool was peer-reviewed by experienced researchers and piloted by fifteen experienced researchers with a spread of seniority and specialty. Content and face validity were ensured by peer-review and the piloting process. 45 completed responses were collected. 

Results

68% of countries had eligibility criteria for metabolic surgery; 59% adhered to these. 46% had reimbursement criteria for metabolic surgery. 41% had eligibility criteria for plastic surgery and 31% reimbursement criteria. Average tariffs for a metabolic procedure varied (€800-€ 16000). MDTs were mandated in 78%, with team members varying significantly. Referral practises differed. In 45% metabolic surgery is performed by pure metabolic surgeons. 23% had a metabolic training program. Access to metabolic surgery was rated poor/ very poor in 33%. 35% had a bariatric registry. 24% required a minimum procedure number for metabolic centres; varying from 25 to 200 procedures.

Conclusions

This is the first study to describe accessibility and quality data on metabolic and body contouring surgery from most European countries. There are myriad differences between European countries in terms of accessibility to metabolic surgery. Lack of funding, education and structure fuels this disparity. We hope this study will impact standardisation of access and quality indicators for metabolic and body contouring surgery across European countries, as well as be a springboard for further evaluation of international metabolic surgery practices.
P-BN02 Experience in Transitioning From Laparoscopic to Robotic-Assisted ParaEsophageal Hernia Repair - A Single Centre Experience
Authors: Azzawi Mohammed Al , Ismael Ghazi , Bolger Jarlath , Robb William
Published: December 2021

Background

Paraesophageal hernias (PEH) constitute only 5% of hiatal hernias. They may give rise to significant post-prandial symptoms, acute episodes of obstruction or gastric ischaemia and patient mortality.  Surgical repair of symptomatic PEHs is the current standard of care. This study explores our centre’s experience with the introduction of Robotic Assisted PEH (RA-PEH) repair in comparison to our longer established technique of laparoscopic repair.

Methods

Retrospective review of all laparoscopic and robotic PEH repair using the DaVinci Xi between January 2017 and May 2020 by a single surgeon in 2 institutions. A total of 27 cases were included in our review. An analysis of patient demographics, operative time and approach, morbidity and mortality was performed. 

Results

Sixteen patients underwent laparoscopic repairs and 11 underwent elective robotic repair. Fundoplication was performed in both groups while mesh repair was used in 18% of the laparoscopy group. Type IV hiatal hernia was found in 50% and 37% in the laparoscopy and RA-PEH groups, respectively. Mean operative time was 144 minutes in the laparoscopy group and 153 minutes for RA-PE (p = 0.07). Median length of stay was 2 days for both groups (p = 0.18). Post-operative morbidity occurred in 37% and 9% in the laparoscopy and RA-PEH groups respectively (p = 0.18). There was 1 case of acute post-operative recurrence and re-operation in the laparoscopy group.

Conclusions

Minimally invasive surgery is the standard of treatment in PEH repair. The robotic technique is a safe and effective approach when compared to the standard laparoscopic repair. It may have an advantage in reducing reliance on the necessity of having experienced assistance in the operating theatre without utilising more theatre time.
P-BN03 A systematic review of pre-operative low-calorie diets for laparoscopic cholecystectomy
Authors: Cheung Tiffany , Findlay John
Published: December 2021

Background

Laparoscopic cholecystectomy is the fourth most common procedure in the UK. Increased liver adiposity, commonly encountered in obesity, anecdotally may increase technical difficulty and surgical risk. Pre-operative low-calorie diets are well-established in bariatric surgery to reduce liver bulk, thereby ameliorating difficulty and risk. Similar diets are often used before laparoscopic cholecystectomy, however, the supporting evidence base is unclear; we performed the first systematic review on their use in this context.

Methods

PubMed, Embase and Cochrane Central Register of Controlled Trials databases were searched in February 2021. We included English language clinical studies describing pre-operative low-calorie diet for laparoscopic cholecystectomy. Data were extracted for specifics of / adherence to diet, weight change, operative time / difficulty, complications and length of stay. Study quality was qualified using Scottish Intercollegiate Guidelines Network criteria and Jadad score.

Results

One randomised controlled trial (RCT) and one prospective observational study were identified. Both utilised a pre-operative very low-calorie diet of < 800 kcal/day. Overall weight loss was greater in patients deemed compliant with the intervention. Both demonstrated tendency towards reduced operative difficulty with the intervention. Only the RCT found improvement in operative time.

Conclusions

Pre-operative very low-calorie diets (< 800 kcal/day for two weeks) may aid weight loss and reduce operative difficulty in laparoscopic cholecystectomy, although evidence supporting their continued use is limited. Further RCTs are warranted to fully evaluate their role in clinical and cost-effectiveness.
P-BN24 Quality assessment of online patient information on upper gastrointestinal endoscopy using the Modified Ensuring Quality Information for Patients (EQIP) tool
Authors: Miller Gillian , Chien Siobhan , Huang Ivory , Cunningham Danielle , Carson Daniel , Gall Lewis , Khan Khurram
Published: December 2021

Background

Online resources are rapidly becoming patients’ primary source of healthcare information due to the Internet’s ease of access. The availability of high-quality online information is paramount to improving patient education and clinical outcomes. Upper gastrointestinal (UGI) endoscopy is the gold standard investigation for UGI symptoms, yet little is known regarding the quality of patient oriented websites. This study aims to analyse the quality of online patient information on UGI endoscopy using the modified Ensuring Quality Information for Patients (EQIP) tool.

Methods

A systematic review was conducted using 10 search terms. The top 100 websites for each term identified using Google search were assessed using the modified EQIP tool (score 0-36). Sub-analysis was performed on high-scoring websites. Websites for medical professional use or containing video and marketing content were excluded.

Results

378 websites were eligible for analysis. The median modified EQIP score for UGI endoscopy was 18/36 (IQR 14-21). Median EQIP scores for the content, identification and structure domains were 8/18, 1/6 and 9/12, respectively. Websites produced by government health departments and NHS hospitals had a higher modified EQIP score (p = 0.007). Complication rates were included in only 20.4% of websites. High-scoring websites were significantly more likely to provide balanced information on risks and benefits (94.6% vs. 34.4%; p < 0.001).

Conclusions

The current quality of online patient information on UGI endoscopy is limited, with minimal information available on risks of the procedure, potentially hindering patients’ ability to make informed healthcare decisions. There is an immediate need for high-quality online resources to improve patient education.
P-BN30 Retroperitoneal biloma: a case report of spontaneous retroperitoneal bike leak and collection
Authors: Bickerton Robert , Godden Amy , Bointas Georgios , Bakhet Marize , Bingham George , Gonzalez Hector
Published: December 2021

Background

Retroperitoneal biloma is a rare complication of gallstone disease. Only a handful of cases have been reported in the literature with various mechanisms postulated.  Here, we report a case of spontaneous retroperitoneal biloma arising from gallbladder perforation.

Methods

An 87-year-old female patient presented with right upper quadrant pain in the context of known gallstone disease. Inflammatory markers and liver function tests were deranged. Cross sectional imaging found acute cholecystitis and a gallbadder neck perforation with an impacted 2cm proximal common bile duct (CBD) stone.  

A cholecystostomy was placed and she improved clinically. However, inflammatory markers remained high, and a subsequent computed tomography (CT) found a large collection in the retroperitoneum.  

Results

The retroperitoneal collection measured 14cm x 7cm, and there had been evidence on prior CT scans of retroperitoneal inflammation. It was urgently drained under ultrasound guidance and found to contain bilious content.  Subsequent endoscopic retrograde cholangiopancreatography (ERCP) was unable to retrieve the CBD stone, but left stents either side of the stone. The patient clinically and biochemically improved. She was discharged and had an elective ERCP, which successfully retrieved the stone, with a plan for urgent elective laparoscopic cholecystectomy. 

Conclusions

Here, we report an interesting case of retroperitoneal biloma successfully managed with ultrasound-guided drainage.

Perforation of the distal CBD can result in retroperitoneal bile leak, but the proximal CBD stone in this case would have likely prevented passage of bile. A more likely cause is adhesion of the gallbladder neck to the posterior parietal peritoneum due to chronic inflammation, with subsequent perforation and release of bile into the retroperitoneum. This has previously been described in the literature. Regardless of mechanism, knowledge of the potential for this rare complication is important for anticipating and appropriately managing complications of gallbladder perforation.
P-BN38 Patient Outcomes Following Laparoscopic Cholecystectomy after a Diagnosis of Gall Bladder (GB) Polyp over 10 Years
Authors: Richardson Tom , Karunanithy Vithurshanan , Kumar Akshay , Thomas Sudeep , Khan Saad
Published: December 2021

Background

Gall Bladder (GB) polyps are elevations of the GB wall that project into the lumen. They are a rare incidental radiological finding with prevalence of 0.3% to 9.5%. Although the majority of these may be pseudopolyps correct follow up and management is essential as to ensure that true polyps, which may be malignant or have malignant potential, are not missed. We conducted a retrospective study assessing patient factors that may predispose to the finding of true polyps. Patient outcomes including histological findings as well as ongoing symptoms and further investigations or emergency attendances were also assessed.

Methods

Patients were identified for this retrospective ten year cohort study using International Statistical Classification of Diseases and Related Health Problems (ICD 10) code K 82.8, other specified diseases of gall bladder. Patients with other diagnoses such as gall bladder dysfunction were excluded after review of electronic patient record (EPR) (Sunrise, Allscripts). EPR allowed for review of emergency attendances, clinic letters, investigations and histological results for those diagnosed with a gall bladder polyp. Analysis was performed with Microsoft Excel.

Results

35% patients had a laparoscopic cholecystectomy and the average wait time for surgery was 19 months but only 11% of patients were found to have true GB polyps on histology. Other histological findings included chronic cholecystitis (96%), cholesterolsis (33%) and stones 35%. Only 12% of those booked straight to laparoscopic cholecystectomy re-presented post operatively compared to 37% of those operated on after a period of surveillance.  Patients booked straight for laparoscopic cholecystectomy, or diagnosed with polyps >10mm in size, were statistically more likely to have a true GB polyp (P < 0.05), however, gender, ethnicity, and whether an isolated polyp or multiple were diagnosed made no statistical difference to detection of a true polyp (P > 0.05).

Conclusions

From this series of patients true polyps are most likely to be identified if it is larger than 10mm at diagnosis and operated on straight away. 96% of all patients, however, displayed histological features of chronic cholecystitis. This suggests that proceeding to laparoscopic cholecystectomy straight from diagnosis of a GB polyp can be justified. Only 1patient in our cohort returned normal GB histology.. Following diagnosis of a GB polyp, the option of operation versus surveillance should be discussed wirth individual patients and decisions based on assessment of risks and benefits should be made. Further research will help identify those with a predisposition to high-risk true polyps.
P-BN39 The perils of MRCP requesting and early associations of data quality and likelihood of a diagnostic result
Authors: Jones Callum , Barton Helena , Pathak Samir , Rees Jonathan
Published: December 2021

Background

MRCP (Magnetic resonance cholangiopancreatography) is used most to assess the biliary tree for stones or strictures. Recently, MRCP availability has increased, and it is extensively used to detect of common bile duct (CBD)stones although very frequently no stones are seen. Indeed, the currently recruiting sunflower RCT aims to determine the clinical and cost effectiveness of expectant management versus MRCP in patients undergoing laparoscopic cholecystectomy at low or moderate risk of common bile duct stones. However, it is critical when requesting an investigation that adequate information is provided.  This work aimed, to describe the adequacy of information provided and correlate this with the MRCP result. We hypothesised that the less information that was provided the more common a normal result would be.

Methods

For a three month period (January 2021 to April 2021) all MRCP requests to detect the presence of a CBD stone were reviewed and data obtained from the Radiology CRIS (CDN Radiology Information System, CDN, Sydney, Aus.). The requesting information was compared to three pre-defined criteria (CBD diameter, presence of gallstones and LFT details) that were agreed as the optimal information that a reporting radiologist would require. The number of key pieces of information for each request and whether the request identified a CBD stone were identified. The proportion of MRCPs detecting a CBD stone was calculated according to the number of key pieces of information provided.    

Results

56 patients were identified, of which 16 (29%) patients had CBD stones. In 24/56 (43%) patients the presence of gallstones on a previous ultrasound was provided, 14/56 (25%) of patients had information about LFTs including bilirubin and a trend in LFTs was not stated for any patient (0/56; 0%).  The rate of stone detection was calculated by the number of pieces of information provided. The rate was 71% (5/7) when all 3 pieces of data were provided, 31% (2/13) when two piece of information were provided, 30% (8/27) when a single piece of information was provided, and only 11% (1/11) when none of the specified data were provided.

Conclusions

It is uncommon for adequate clinical information to be provided in MRCP requests and in 16% of request no key information was provided. The LFT results were frequently omitted and the trend in LFTs never stated. The more key data provided in the request saw a higher proportion of MRCPs where a CBD stone was identified. We recommend that maximal clinical information is mandated for MRCP request perhaps using mandatory fields on electronic requesting systems and that  these systems are also used to facilitate recruitment to clinical trials such the Sunflower RCT.
P-BN47 Acute cholecystectomy in elderly - Age is not a limit
Authors: Gupta Aayush , Rashid Muhammad Umair , Rupasinghe Namal , Adjepong Samuel , Rink James , Kirby George , Jain Rajesh , Riera Manel , Parampalli Umesh , Pattar Jayaprakash
Published: December 2021

Background

Acute or hot cholecystectomy (AC) has been established as a safe and efficacious modality of managing acute biliary pathology. However, it has been performed with caution in the elderly (defined by the world health organisation as patients over the age of 65). The NICE guidance in this area does not preclude this practise on elderly patients. Our acute cholecystectomy service treats patients of all ages according to performance status and fitness for surgery rather than age we audited our results in this age group.

Methods

All patients over the age of 65 who underwent acute cholecystectomy in the dedicated emergency cholecystectomy lists were audited from the period starting 31st December 2019 to 31st June 2021. Patient demographics, co-morbidies and surgical factors were recorded. The primary outcomes measure was in hospital stay and re-admission, secondary outcome were complications and perioperative mortality.

Results

41 elderly patients underwent AC during the audit period, (male 18: female 23). Majority of patients had acute cholecystitis 30(73%). The median inpatient stay following surgery was 2 days(range 2-5 days) and the median admission to surgery time was 6 days (range 5-12 days). Only 3(7%) patients had a subtotal cholecystectomy. There was only 3 complications from surgery which were all between a clavien-dindo score of 2 and 3. There were 3 readmission in the immediate post-operative period. There was one 30-day mortality which was from necrotising pancreatitis as a result of ERCP and not from the operation.

Conclusions

Acute cholecystectomy in this age group appears to be safe and effective way to treat acute biliary pathology and compares similarly to the outcomes in the younger groups.
P-BN51 Subtotal cholecystectomy: risk factors and patient outcomes
Authors: Lucocq James , Hamilton David , Scollay John , Patil Pradeep
Published: December 2021

Background

A subtotal cholecystectomy (SC) is indicated when a total cholecystectomy (TC) cannot be achieved without the risk of causing significant harm, the most feared complication being a bile duct injury. The aims of the present study were to identify patients at risk of SC, to compare the peri- and post-operative course between SC and TC and to compare outcomes between fenestrated and reconstituting subtypes.

Methods

All planned laparoscopic cholecystectomies across three surgical units over a population of 493,000 between 2015 and 2019 were considered. Data were collected retrospectively using electronic databases and included pre-operative, operative and post-operative data over a 100-day follow-up period. Variables associated with SC were identified using multivariate logistic regression. Outcomes following SC were compared with TC using univariate analysis, specifically chi-squared and Mann-Whitney U tests. The subtype of SC was documented and outcomes were compared between groups.

Results

The rate of SC was 3.4% (94/2768). Variables positively associated with SC included male sex (OR-2.33;p<0.001), age≥60 (OR-1.79;p=0.009), 2 previous admissions (OR-1.76;p=0.043), ≥3 previous admissions (OR-3.10;p=0.003), emergency cholecystectomy (OR-2.01;p=0.002); cholecystitis (OR-4.92;p<0.001) and pre-operative ERCP (OR-2.23;p<0.002). Patients with SC versus TC were more likely to suffer intra-operative complications (RR-13.1;p<0.001), post-operative complication (RR-6.7;p<0.001), require post-operative imaging/intervention (RR-4.0;p<0.001) and be re-admitted (RR-4.2; p < 0.001). The rate of bile duct injury was 0% in SC patients. The rate of post-operative bile leak was higher where the cystic duct was left open versus closed (RR-2.9;p=0.03) and in fenestrating SC versus reconstituting SC (35.7% versus 0%;p=0.002). Drain duration was reduced in reconstituting SC (p < 0.001).

Conclusions

The risk of SC can be explained by a number of patient specific factors and the risk should be emphasized in these patients during the consent process and should influence surgical decision making. The morbidity following a subtotal cholecystectomy is markedly higher than that of a total cholecystectomy but can be performed without significant risk of bile duct injury. Reconstituting SC and closure of the cystic duct reduces rates of post-operative bile leaks and duration of drains.
P-BN54 The outcomes after a Laparoscopic subtotal cholecystectomy
Authors: wintrip Dorothy , Thomas Christophe
Published: December 2021

Background

Laparoscopic subtotal cholecystectomy (LSC) is a recognised option when the “critical view” cannot be safely delineated. It carries a high morbidity rate as there are increased frequencies of a bile leak occurring however reducing the risk of bile duct injury. LSC can be further divided into fenestrating or reconstituting cholecystectomy, the later entails closing the remnant. The literature state reconstituting cholecystectomy reduced rate of bile leak. We reviewed our cases to analyse the complication rates of LSC and there outcomes.

Methods

A retrospective review of patients who underwent a laparoscopic subtotal cholecystectomy (LSC) using electronic records between January 2015 to March 2021.

A total of 160 patients, with a mean age of 65, 51% male and 49% female.

Results

76% of LSC were performed as an emergency. Mean operation length was 96min and the mean blood loss 92ml. Complications occurred in 50% of patients.

Post operatively 22% underwent an ERCP and the re-operation rate was 9%.

The mean length of stay was 8 days.

Conclusions

Based on our results LSC carry a high rate of bile leak with the majority requiring intervention in the form of ERCP or laparoscopy and wash out. A reconstituting cholecystectomy, closing with an endoloop of suture seems to slightly reduce the rate of bile leak. LSC are only performed when managing a difficult gallbladder with a dense/ inflamed Calot's triangle. There were no mortalities associated with a LSC.