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Background: The confirmatory test for sphincter of Oddi dysfunction (SOD) is manometry (SOM) which may be hazardous. When SOM is equivocal, the decision to treat by sphincterotomy, entailing further risk, [...]

Background: Children with abdominal pain, vomiting, and/or bloating often have gastric dysfunction such as delayed gastric emptying (GE). GE studies on children are difficult to perform due to the necessity [...]

Background and Aims: Enteral feed given as a bolus has a half emptying time (t 1/2) of 90 min. No data are available on gastric emptying patterns during continuous nasogastric [...]

Introduction: Identification of LOS by visual inspection at endoscopy is unreliable and often impossible. Knowledge of the sphincter position detected by station pull through manometry (SPM) can not be effectively [...]

Introduction: Sphincter of Oddi dysfunction (SOD) represents a difficult diagnostic challenge. Sphincter of Oddi manometry is the gold standard diagnostic method, but this is technically difficult, carries significant risk, and [...]

Introduction: Patients with globus sensation are usually referred to an ENT specialist for possible malignancy. However, in most patients, flexible laryngoscopy shows no abnormalities, and further management is often unclear. [...]

Background: Small bowel manometry (SBM) has widely been used to investigate adult patients with gastrointestinal motility disorder. However, the use of this technique to paediatrics is uncommon. The aim of this study was to evaluate feasibility of SBM on paediatric patients with suspected small intestinal motility disorder. Methods: We have performed SBM on 14 paediatric patients (age range 2-10 years) who had symptom(s) including recurrent abdominal pain (n = 10), nausea (n = 5), vomiting (n = 7), abdominal distension (n = 2) and constipation (n = 2). A 3-channel manometry catheter was introduced nasally and placed in the proximal small bowel under fluoroscopic control. Ambulatory recordings were made for 24 hours using a portable recorder. Recorded data were analysed using dedicated software. Results: Four had normal motility when applied to the normal ranges in adults. At least one of the following abnormalities was found in eight patients; possible neuropathy findings including excess of motor activity (n = 3), prolonged Phase III (n = 2), Phase III-like prolonged bursts (n = 3), non-propagated Phase III (n = 2), retrograde propagation of Phase III (n = 2), and Iow-amplitude Phase III (n = 1) suggesting possible myopathy. Intubation failed in two patients due to no migrations of the catheter into the small intestine. Summary: In this study a high proportion of the patients had abnormal small intestinal motility and this suggests that SBM can be used to evaluate those conditions. Normal values during infant and childhood development need establishing before adopting the technique for clinical diagnosis. [ABSTRACT FROM AUTHOR]

Sphincter of Oddi dysfunction (SOD) is a cause of postcholecystectomy pain. Current gold-standard diagnosis is by measurement of basal pressure by sphincter of Oddi manometry (SOM), and if elevated an endoscopic sphincterotomy (ES) is performed. Both these procedures carry significant complication rates. Hepatobiliary scintigraphy has been promoted as a means of assisting management. Aim: to evaluate hepatobiliary scintigraphy (HBS) as a means of screening for SOD and predicting treatment response. Methods: 21 post-cholecystectomy patients were screened by HBS prior to standard evaluation with SOM during ERCP. HBS was performed using a standard protocol. A semi-quantitative scoring system classified scans as positive (SOD) or negative (no SOD). Two observers reviewed all 21 scintigrams. SOM was regarded as diagnostic of SOD if sphincter base pressure was > 40 mm Hg. If elevated, an ES was performed and a successful result was defined as an improvement in symptoms. Results: 17 of our patients were female, average age 42.4 + 4.0 years. Agreement was 100% between observers. Conclusions: HBS can be interpreted reliably between observers. HBS is a poor screening tool in isolation, but may prove a useful adjunct to manometry in predicting ES outcome. [ABSTRACT FROM AUTHOR]

Introduction: Circadian rhythms for protein transcription have recently been identified in the gut? Environmental synchronizers may reset biological clocks, leading to alteration in gut functions, but alteration in bowel transit due to time zone shifts experienced in long haul flight is yet to be reported. Methods: Six men (Age 33.2 +/- 10.6 years) and 3 women (36.7 +/- 7.2) (mean +/- 1 SD) flew from London to California, USA, and back. As a pre-condition to joining the study, they were on no drugs for digestive diseases. We elicited responses pre-, in-, and post-flight and during foreign stay about their bowel habit, stool form scale and abdominal symptoms using validated questionnaires. Paired t-tests were used to examine significant changes in sleep and stool form scale from the pre-flight level. Stool form scale may be used as o guide to intestinal transit time. Results: Sleep duration and times pre-flight, during foreign stay and post flight were not significantly different (p > 0.05). Additionally, there was no reason to believe that the stool changes were attributable to a drastic change in diet. Abdominal symptoms were unremarkable and did not change during foreign stay or on return home from abroad. All our subjects were normal and had an uneventful stay abroad. Average stool consistency changed significantly (p < 0.01) from a lumpy to smooth consistency to a smooth to soft consistency during foreign stay and persisted 4-5 days into post-flight. The respective stool form sca[es were pre-flight 2.8 +/- 1.0, foreign stay 3.5 +/-1.1, post-flight 3.7 +/-1.2. Summary and Conclusion: During a time zone shift of +/- 8h, while the sleep clock was synchronized with the external chock, gut transit, as measured by the stool form scale, failed to synchronize with the external clock, leading to altered bowel habit. Biologic clocks that regulate gut functions may not adapt as readily to time shifts, as does the sleep clock. [ABSTRACT FROM AUTHOR]

23 Children aged between 11 months and 15.5 years were seen in our clinic within the period October 01 2001-2002. They presented with feeding difficulties that required oesophageal manometry, among other diagnostic investigations. The commonest symptoms were dysphagia for solids, regurgitation, and vomiting, in order of frequency. Lower Oesophageal Sphincter (LOS) pressure and body motility were measured using a standard eight channel, water perfused adult catheter (3.9 mm diameter) or a 2.3 mm catheter purpose designed for paediatric use (Mediplast). LOS pressure and oesophageal body motility were measured using a Flexilog 4000 recording system. Nine out of 23 patients had a hypertensive LOS (pressure > 26 mm Hg). These patients with hypertensive LOS but without achalasia often had regurgitation and vomiting as major presenting symptoms. Only 2 out of 23 patients had achalasia and only one of the two had a hypertensive LOS. Non-specific motility disorder (7/23), in which there were few peristaltic waves with a majority of simultaneous contractions, was the commonest cause of dysphagia. Of significance was a subgroup (4/23) with a partially relaxing LOS (residual pressure 6-11 mm Hg) but who did not have achalasia. This group had varied symptoms such as vomiting, regurgitation, and dysphagia for solids. A large hiatus hernia (7 cm) was the only finding in an adolescent girl with unexplained vomiting, normal oesophageal body motility, and "normal" OGD. in summary, children with feeding problems who present with regurgitation, vomiting, and dysphagia for solids are most likely to have a hypertensive LOS or non-specific oesophageal dysmotility rather than achalasia. Unexplained vomiting with normal LOS function and body motility may be due to hiatus hernia, which could be missed during OGD. In conclusion, oesophageal manometry is an essential diagnostic tool in the investigation of upper gastrointestinal manifestations. From our experience, it is best suited to... [ABSTRACT FROM AUTHOR]

Flavin adenine dinucleotide (FAD) is an essential cofactor for numerous flavoenzymes present in all living organisms. The biosynthesis of FAD from riboflavin involves two sequential reactions catalyzed by riboflavin kinase and flavin adenine dinucleotide synthase (FADS). Entamoeba histolytica , the protozoan parasite responsible for amebiasis, apparently lacks a gene encoding FADS that share similarity with bacterial and eukaryotic canonical FADS, yet it can synthesize FAD. In this study, we have identified the gene responsible for FADS and thoroughly characterized physiological and biochemical properties of FADS from E. histolytica . Phylogenetic analysis revealed that the gene was likely laterally transferred from archaea. The kinetic properties of recombinant EhFADS were consistent with the notion that EhFADS is of archaeal origin, exhibiting K M and k cat values similar to those of the arachaeal enzyme while significantly differing from the human counterpart. Repression of gene expression of EhFADS by epigenetic gene silencing caused substantial reduction in FAD levels and parasite growth, underscoring the importance of EhFADS for the parasite. Furthermore, we demonstrated that EhFADS gene silencing reduced thioredoxin reductase activity, which requires FAD as a cofactor and makes the ameba more susceptible to metronidazole. In summary, this study unveils unique evolutionary and biochemical features of EhFADS and underscores its significance as a promising drug target in combating human amebiasis.IMPORTANCEFAD is important for all forms of life, yet its role and metabolism are still poorly studied in E. histolytica , the protozoan parasite causing human amebiasis. Our study uncovers the evolutionary unique key enzyme, archaeal-type FADS for FAD biosynthesis from E. histolytica for the first time. Additionally, we showed the essentiality of this enzyme for parasite survival, highlighting its potential as target for drug development against E. histolytica infections., Competing Interests: The authors declare no conflict of interest.

Gastroesophageal reflux disease (GERD) is commonly encountered in clinical practice in Sri Lanka. However, its prevalence in Sri Lanka is unknown. Our objective was to study the island-wide prevalence of GERD symptoms in Sri Lanka and its associated factors. A total of 1200 individuals aged 18-70 years (male: female 1: 1.16, mean age 42.7 years [SD 14.4 years]). were recruited from all 25 districts of the country, using stratified random sampling. An interviewer-administered, country-validated questionnaire was used to assess the GERD symptom prevalence and associated factors. Weight, height, waist, and hip circumference were measured. Heartburn and/or regurgitation at least once a week, an internationally used criterion for probable GERD was used to diagnose GERD. In this study, GERD symptom prevalence was 25.3% (male 42.1% and female 57.9%). Factors independently associated with GERD were inadequate sleep, snacking at midnight, sleeping within two hours of consuming a meal, skipping breakfast, increased mental stress, and certain medications used such as statins, and antihypertensive medications (p<0.001, univariate and logistic regression analysis). 38.4% of the study population have been using medication for heartburn and regurgitation in the past 3 months and 19.8% were on proton pump inhibitors. To conclude, the prevalence of GERD symptoms in Sri Lanka (25.3%) is higher than its estimated global prevalence of 13.8%. Several meal-related lifestyle habits, mental stress, and the use of some medications are significantly associated with GERD, indicating the importance of lifestyle modification and stress reduction in its management., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Wickramasinghe et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

DNA polymerases synthesize DNA from deoxyribonucleotides in a semiconservative manner and serve as the core of DNA replication and repair machinery. In eukaryotic cells, there are 2 genome-containing organelles, mitochondria, and plastids, which were derived from an alphaproteobacterium and a cyanobacterium, respectively. Except for rare cases of genome-lacking mitochondria and plastids, both organelles must be served by nucleus-encoded DNA polymerases that localize and work in them to maintain their genomes. The evolution of organellar DNA polymerases has yet to be fully understood because of 2 unsettled issues. First, the diversity of organellar DNA polymerases has not been elucidated in the full spectrum of eukaryotes. Second, it is unclear when the DNA polymerases that were used originally in the endosymbiotic bacteria giving rise to mitochondria and plastids were discarded, as the organellar DNA polymerases known to date show no phylogenetic affinity to those of the extant alphaproteobacteria or cyanobacteria. In this study, we identified from diverse eukaryotes 134 family A DNA polymerase sequences, which were classified into 10 novel types, and explored their evolutionary origins. The subcellular localizations of selected DNA polymerases were further examined experimentally. The results presented here suggest that the diversity of organellar DNA polymerases has been shaped by multiple transfers of the PolI gene from phylogenetically broad bacteria, and their occurrence in eukaryotes was additionally impacted by secondary plastid endosymbioses. Finally, we propose that the last eukaryotic common ancestor may have possessed 2 mitochondrial DNA polymerases, POP, and a candidate of the direct descendant of the proto-mitochondrial DNA polymerase I, rdxPolA, identified in this study., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

Background: Mechanisms underlying perception of dysphagia and chest pain have not been completely elucidated, although oesophageal mucosal afferent nerves might play an important role., Aims: To evaluate the relationship between oesophageal mucosal afferent nerves and the severity of dysphagia and chest pain in oesophageal motility disorders., Methods: We prospectively recruited patients with oesophageal motility disorders having dysphagia and/or chest pain from whom oesophageal biopsies were obtained. High-resolution manometry classified patients into disorders of oesophagogastric junction (OGJ) outflow and disorders of peristalsis. Symptom severity was assessed using validated questionnaires including Brief Oesophageal Dysphagia Questionnaire (BEDQ). Immunohistochemistry was performed on oesophageal biopsies to evaluate the location of calcitonin gene-related peptide (CGRP)-immunoreactive mucosal afferent nerves. Findings were compared to existing data from 10 asymptomatic healthy volunteers., Results: Of 79 patients, 61 patients had disorders of OGJ outflow and 18 had disorders of peristalsis. CGRP-immunoreactive mucosal nerves were more superficially located in the mucosa of patients with oesophageal motility disorders compared to healthy volunteers. Within disorders of OGJ outflow, the location of CGRP-immunoreactive nerves negatively correlated with BEDQ score both in the proximal (ρ = -0.567, p < 0.001) and distal oesophagus (ρ = -0.396, p = 0.003). In the proximal oesophagus, strong chest pain was associated with more superficially located mucosal nerves than weak chest pain (p = 0.04). Multivariate analysis showed superficial nerves in the proximal oesophagus was independently associated with severe dysphagia in disorders of OGJ outflow (p = 0.008)., Conclusions: Superficial location of mucosal nerves in the proximal oesophagus might contribute to symptoms, especially severe dysphagia, in disorders of OGJ outflow., (© 2023 John Wiley & Sons Ltd.)

Most species belonging to the diplomonad genera, Trepomonas and Hexamita , are considered to have secondarily adapted to free-living lifestyles from the parasitic ancestor. Here, we report the annotated transcriptome data of Trepomonas sp. NIES-1444 and Hexamita sp. NIES-1440, the analysis of which will provide insights into the lifestyle transitions., Competing Interests: The authors declare no conflict of interest.

Background/aims: Stress is a known associated factor for gastroesophageal reflux disease (GERD). However, the dynamics between stress and GERD are not fully studied, especially in Sri Lanka. Our objective was to assess it., Methods: For this cross-sectional descriptive study, 1200 individuals (age ranged 18-70 years, mean 42.7 years [SD 14.4 years], 46.1% males), were recruited using stratified random cluster sampling from all 25 districts of Sri Lanka. An interviewer-administered questionnaire, which included a country-validated GERD symptom screening tool, and the Perceived Stress Scale (PSS), was used to assess GERD symptoms and stress. Probable GERD was defined as those having heartburn and/ or regurgitation at least once per week which is on par with globally accepted criteria. Those who did not fulfill these criteria were considered as controls., Results: PSS score was higher in those with probable GERD (mean 13.75 [standard deviation (SD) 6.87]) than in controls (mean 10.93 [SD 6.80]), (p <0.001, Mann-Whitney U test). The adjusted odds ratio for GERD symptoms was 1.96 times higher (95% confidence interval 1.50-2.55) in the moderate to high-stress level compared to the low-stress level participants. PSS score correlated significantly with the GERD screening tool score (R 0.242, p <0.001). Heartburn, regurgitation, chest pain, cough, and burping were significantly frequent in those with moderate to high-stress levels (p <0.001). Those with higher stress scores were more likely to use acid-lowering drugs (p = 0.006)., Conclusions: Individuals exposed to higher levels of stress are more likely to have GERD symptoms. Therefore, stress reduction should be an important part of GERD symptom management., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Wickramasinghe et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: The esophagogastric junction (EGJ) is classified into 3 anatomical subtypes according to lower esophageal sphincter-crural diaphragm (LES-CD) separation. We aimed to assess their relationship to esophageal motility, reflux characteristics, and symptom perception., Methods: We analyzed data from 1740 consecutive patients with typical reflux symptoms, who underwent high resolution manometry and a 24-h pH-impedance study during a 13-year period. A diagnosis of gastroesophageal reflux disease (GERD) was made if acid exposure time (AET) was >6%. EGJ types were classified as 1, 2, or 3, if LES-CD separation was up to 1 cm, 1-3 cm, or ≥3 cm, respectively., Results: EGJ type distribution was 72.2%, 22.1% and 5.7%, for types 1, 2 and 3, respectively. GERD was diagnosed in 31.2% and was more common among patients with EGJ type 2/3 vs. 1 (P<0.001). Length of LES-CD separation significantly correlated with AET and number of reflux episodes. Patients with type 2 or 3 EGJ more often showed ineffective or absent peristalsis compared with type 1 (P=0.008 and P<0.001 respectively). In the multivariate analysis, EGJ type 2/3 correlated with AET (P=0.001) and reflux episodes (P=0.041) but not with positive symptomatic markers or with ineffective/absent peristalsis., Conclusions: Our study confirms that EGJ anatomical morphology is a strong risk factor for GERD and correlates with both AET and the number of reflux events, though the length of separation is more important than the type. The multivariate analysis revealed that EGJ type 2 or 3 was not correlated with symptom perception or esophageal hypomotility., Competing Interests: Conflict of Interest: None, (Copyright: © Hellenic Society of Gastroenterology.)

Background: Diplonemid flagellates are among the most abundant and species-rich of known marine microeukaryotes, colonizing all habitats, depths, and geographic regions of the world ocean. However, little is known about their genomes, biology, and ecological role., Results: We present the first nuclear genome sequence from a diplonemid, the type species Diplonema papillatum. The ~ 280-Mb genome assembly contains about 32,000 protein-coding genes, likely co-transcribed in groups of up to 100. Gene clusters are separated by long repetitive regions that include numerous transposable elements, which also reside within introns. Analysis of gene-family evolution reveals that the last common diplonemid ancestor underwent considerable metabolic expansion. D. papillatum-specific gains of carbohydrate-degradation capability were apparently acquired via horizontal gene transfer. The predicted breakdown of polysaccharides including pectin and xylan is at odds with reports of peptides being the predominant carbon source of this organism. Secretome analysis together with feeding experiments suggest that D. papillatum is predatory, able to degrade cell walls of live microeukaryotes, macroalgae, and water plants, not only for protoplast feeding but also for metabolizing cell-wall carbohydrates as an energy source. The analysis of environmental barcode samples shows that D. papillatum is confined to temperate coastal waters, presumably acting in bioremediation of eutrophication., Conclusions: Nuclear genome information will allow systematic functional and cell-biology studies in D. papillatum. It will also serve as a reference for the highly diverse diplonemids and provide a point of comparison for studying gene complement evolution in the sister group of Kinetoplastida, including human-pathogenic taxa., (© 2023. The Author(s).)

Two autophagy-related (ATG) ubiquitin-like conjugation systems, the ATG12 and ATG8 systems, play important roles in macroautophagy. While multiple duplications and losses of the ATG conjugation system proteins are found in different lineages, the extent to which the underlying systems diversified across eukaryotes is not fully understood. Here, in order to understand the evolution of the ATG conjugation systems, we constructed a transcriptome database consisting of 94 eukaryotic species covering major eukaryotic clades and systematically identified ATG conjugation system components. Both ATG10 and the C-terminal glycine of ATG12 are essential for the canonical ubiquitin-like conjugation of ATG12 and ATG5. However, loss of ATG10 or the C-terminal glycine of ATG12 occurred at least 16 times in a wide range of lineages, suggesting that possible covalent-to-non-covalent transition is not limited to the species that we previously reported such as Alveolata and some yeast species. Some species have only the ATG8 system (with conjugation enzymes) or only ATG8 (without conjugation enzymes). More than 10 species have ATG8 homologs without the conserved C-terminal glycine, and Tetrahymena has an ATG8 homolog with a predicted transmembrane domain, which may be able to anchor to the membrane independent of the ATG conjugation systems. We discuss the possibility that the ancestor of the ATG12 and ATG8 systems is more similar to ATG8. Overall, our study offers a whole picture of the evolution and diversity of the ATG conjugation systems among eukaryotes, and provides evidence that functional diversifications of the systems are more common than previously thought. Abbreviations : APEAR: ATG8-PE association region; ATG: autophagy-related; LIR: LC3-interacting region; NEDD8: neural precursor cell expressed, developmentally down-regulated gene 8; PE: phosphatidylethanolamine; SAMP: small archaeal modifier protein; SAR: Stramenopiles, Alveolata, and Rhizaria; SMC: structural maintenance of chromosomes; SUMO: small ubiquitin like modifier; TACK: Thaumarchaeota, Aigarchaeota, Crenarchaeota, and Korarchaeota; UBA: ubiquitin like modifier activating enzyme; UFM: ubiquitin fold modifier; URM: ubiquitin related modifier.

Dinoflagellates possess plastids that are diverse in both pigmentation and evolutionary background. One of the plastid types found in dinoflagellates is pigmented with chlorophylls a and b (Chl a + b ) and originated from the endosymbionts belonging to a small group of green algae, Pedinophyceae. The Chl a + b -containing plastids have been found in three distantly related dinoflagellates Lepidodinium spp., strain MGD, and strain TGD, and were proposed to be derived from separate partnerships between a dinoflagellate (host) and a pedinophycean green alga (endosymbiont). Prior to this study, a plastid genome sequence was only available for L. chlorophorum , which was reported to bear the features that were not found in that of the pedinophycean green alga Pedinomonas minor , a putative close relative of the endosymbiont that gave rise to the current Chl a + b -containing plastid. In this study, we sequenced the plastid genomes of strains MGD and TGD to compare with those of L. chlorophorum as well as pedinophycean green algae. The mapping of the RNA-seq reads on the corresponding plastid genome identified RNA editing on plastid gene transcripts in the three dinoflagellates. Further, the comparative plastid genomics revealed that the plastid genomes of the three dinoflagellates achieved several features, which are not found in or much less obvious than the pedinophycean plastid genomes determined to date, in parallel., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Matsuo, Morita, Nakayama, Yazaki, Sarai, Takahashi, Iwataki and Inagaki.)

By clarifying the phylogenetic positions of 'orphan' protists (unicellular micro-eukaryotes with no affinity to extant lineages), we may uncover the novel affiliation between two (or more) major lineages in eukaryotes. Microheliella maris was an orphan protist, which failed to be placed within the previously described lineages by pioneering phylogenetic analyses. In this study, we analysed a 319-gene alignment and demonstrated that M. maris represents a basal lineage of one of the major eukaryotic lineages, Cryptista. We here propose a new clade name 'Pancryptista' for Cryptista plus M. maris . The 319-gene analyses also indicated that M. maris is a key taxon to recover the monophyly of Archaeplastida and the sister relationship between Archaeplastida and Pancryptista, which is collectively called 'CAM clade' here. Significantly, Cryptophyceae tend to be attracted to Rhodophyta depending on the taxon sampling (ex., in the absence of M. maris and Rhodelphidia) and the particular phylogenetic 'signal' most likely hindered the stable recovery of the monophyly of Archaeplastida in previous studies.

Background & Aims: Reflux hypersensitivity (RH), a functional esophageal disorder, is detected in 14%-20% of patients who present with typical esophageal symptoms. As many as 40% of patients with RH do not respond to treatment with pain modulators or proton pump inhibitors (PPIs); behavior disorders might contribute to lack of treatment efficacy. We aimed to assess the prevalence of behavioral disorders and their effects on typical reflux symptoms in patients with RH., Methods: We performed a retrospective study of 542 patients with PPI-refractory esophageal symptoms (heartburn, regurgitation, or chest pain) or with symptoms that responded to PPI therapy, evaluated for anti-reflux surgery from January 2016 through August 2019 at a single center in London, United Kingdom. We collected data on symptoms, motility, and impedance-pH monitoring and assigned patients to categories of RH (n = 116), functional heartburn (n = 126), or non-erosive reflux disease (n = 300)., Results: Of the 116 patients with a diagnosis of RH, 59 had only hypersensitivity, whereas 57 patients (49.2%) had either excessive supragastric belching (SGB, 39.7%), based on 24-hour impedance-pH monitoring, or rumination (9.5%), based on postprandial manometry combined with impedance. The prevalence of SGB and rumination in patients with RH was significantly higher than in patients with functional heartburn (22%; P < .001). Patients with RH and rumination were significantly younger (P = .005) and had the largest number of non-acid reflux episodes (P = .023). In patients with RH with SGB, SGB episodes were associated with 40.6% of marked reflux symptoms (heartburn, regurgitation, or chest pain), based on impedance-pH monitoring. In patients with RH and rumination, 40% of reflux-related symptoms (mostly regurgitation) were due to possible rumination episodes., Conclusions: Almost half of patients with a diagnosis of RH have behavior disorders, including excessive SGB or rumination. Episodes of SGB or rumination are associated with typical reflux symptoms. Segregation of patients with diagnosis of RH into those with vs without behavioral disorders might have important therapeutic implications., (Copyright © 2021 AGA Institute. Published by Elsevier Inc. All rights reserved.)

We here report the phylogenetic position of barthelonids, small anaerobic flagellates previously examined using light microscopy alone. Barthelona spp. were isolated from geographically distinct regions and we established five laboratory strains. Transcriptomic data generated from one Barthelona strain (PAP020) were used for large-scale, multi-gene phylogenetic (phylogenomic) analyses. Our analyses robustly placed strain PAP020 at the base of the Fornicata clade, indicating that barthelonids represent a deep-branching metamonad clade. Considering the anaerobic/microaerophilic nature of barthelonids and preliminary electron microscopy observations on strain PAP020, we suspected that barthelonids possess functionally and structurally reduced mitochondria (i.e. mitochondrion-related organelles or MROs). The metabolic pathways localized in the MRO of strain PAP020 were predicted based on its transcriptomic data and compared with those in the MROs of fornicates. We here propose that strain PAP020 is incapable of generating ATP in the MRO, as no mitochondrial/MRO enzymes involved in substrate-level phosphorylation were detected. Instead, we detected a putative cytosolic ATP-generating enzyme (acetyl-CoA synthetase), suggesting that strain PAP020 depends on ATP generated in the cytosol. We propose two separate losses of substrate-level phosphorylation from the MRO in the clade containing barthelonids and (other) fornicates.

Background/aims: Mean nocturnal baseline impedance (MNBI) during multichannel intraluminal impedance pH-monitoring (MII-pH) reflects the status of esophageal mucosal integrity. MNBI is suggested as an adjunctive method to distinguish patients with true gastroesophageal reflux disease (GERD) from functional heartburn (FH) and might predict outcomes for anti-reflux treatment. However, current methodology for calculation of MNBI is time-consuming and subject to operator-dependent selection bias. We aim to simplify and provide a more objective method to calculate MNBI., Methods: We retrospectively analyzed 100 MII-pH tracings from 20 patients with erosive reflux disease, 20 with non-erosive reflux disease (NERD), 20 with reflux hypersensitivity, 20 with functional heartburn (FH), and 20 healthy asymptomatic volunteers. We compared the current "conventional" MNBI analysis with our "simple" MNBI analysis measured by selecting the whole supine period using the impedance average calculation function in the MII-pH software., Results: Absolute values were very similar and there was a strong correlation between conventional and simple MNBI values in the most distal channel in all groups ( r ≥ 0.8, P < 0.001) including patients with increased supine acid reflux. Distal esophageal simple MNBI negatively correlated with acid exposure time ( r = -0.695, P < 0.001). Patients with erosive reflux disease and NERD had lower simple MNBI values in the most distal channel compared to other groups ( P < 0.001). With a cutoff value of 1785 ohms, simple MNBI can discriminate patients with GERD from those with reflux hypersensitivity and FH (sensitivity 80.0% and specificity 89.7%)., Conclusion: Simple MNBI analysis provides very similar values and has an excellent correlation with conventional MNBI analysis.

Nucleomorphs are relic endosymbiont nuclei so far found only in two algal groups, cryptophytes and chlorarachniophytes, which have been studied to model the evolutionary process of integrating an endosymbiont alga into a host-governed plastid (organellogenesis). However, past studies suggest that DNA transfer from the endosymbiont to host nuclei had already ceased in both cryptophytes and chlorarachniophytes, implying that the organellogenesis at the genetic level has been completed in the two systems. Moreover, we have yet to pinpoint the closest free-living relative of the endosymbiotic alga engulfed by the ancestral chlorarachniophyte or cryptophyte, making it difficult to infer how organellogenesis altered the endosymbiont genome. To counter the above issues, we need novel nucleomorph-bearing algae, in which endosymbiont-to-host DNA transfer is on-going and for which endosymbiont/plastid origins can be inferred at a fine taxonomic scale. Here, we report two previously undescribed dinoflagellates, strains MGD and TGD, with green algal endosymbionts enclosing plastids as well as relic nuclei (nucleomorphs). We provide evidence for the presence of DNA in the two nucleomorphs and the transfer of endosymbiont genes to the host (dinoflagellate) genomes. Furthermore, DNA transfer between the host and endosymbiont nuclei was found to be in progress in both the MGD and TGD systems. Phylogenetic analyses successfully resolved the origins of the endosymbionts at the genus level. With the combined evidence, we conclude that the host-endosymbiont integration in MGD/TGD is less advanced than that in cryptophytes/chrorarachniophytes, and propose the two dinoflagellates as models for elucidating organellogenesis., Competing Interests: The authors declare no competing interest.

Background/aims: Single swallow integrated relaxation pressure (IRP) on high-resolution manometry (HRM) does not always accurately predict esophagogastric outflow obstruction on timed barium esophagogram (TBE). Furthermore, neither single swallow IRP or TBE is reliable in predicting symptoms, particularly after treatment with dilatation or myotomy. A 200 mL rapid drink challenge (RDC) has been proposed as an adjunctive test during HRM. This serves as a "stress-test" to the esophagogastric junction, and may yield clinically useful parameters. We aim to assess HRM parameters during RDC, and their ability to predict outflow obstruction on TBE in patients with dysphagia, and to correlate with symptoms in patients' achalasia., Methods: Thirty patients with dysphagia were recruited. All underwent standard single swallow HRM analysis, 200 mL RDC, then TBE. RDC parameters, including esophagogastric pressure gradient, IRP, and RDC duration were evaluated. Multiple regression analysis was performed to assess the best predictive parameter for obstruction on TBE. A further 21 patients with achalasia were evaluated with Eckhardt score, single swallow HRM, RDC, and TBE. Parameter correlation with Eckhardt score was evaluated., Results: Mean IRP during RDC was the best HRM parameter at predicting outflow obstruction on TBE. This performed much better in untreated patients (sensitivity 100% and specificity 85.5%) than in previously treated patients (sensitivity 50% and specificity 66%). In patients with achalasia, mean IRP during RDC was the only parameter that correlated with symptom score., Conclusion: Mean IRP during RDC appears to be a clinically useful "stress test" to the esophagogastric junction during HRM.

Rheb is a conserved and widespread Ras-like GTPase involved in cell growth regulation mediated by the (m)TORC1 kinase complex and implicated in tumourigenesis in humans. Rheb function depends on its association with membranes via prenylated C-terminus, a mechanism shared with many other eukaryotic GTPases. Strikingly, our analysis of a phylogenetically rich sample of Rheb sequences revealed that in multiple lineages this canonical and ancestral membrane attachment mode has been variously altered. The modifications include: (1) accretion to the N-terminus of two different phosphatidylinositol 3-phosphate-binding domains, PX in Cryptista (the fusion being the first proposed synapomorphy of this clade), and FYVE in Euglenozoa and the related undescribed flagellate SRT308; (2) acquisition of lipidic modifications of the N-terminal region, namely myristoylation and/or S-palmitoylation in seven different protist lineages; (3) acquisition of S-palmitoylation in the hypervariable C-terminal region of Rheb in apusomonads, convergently to some other Ras family proteins; (4) replacement of the C-terminal prenylation motif with four transmembrane segments in a novel Rheb paralog in the SAR clade; (5) loss of an evident C-terminal membrane attachment mechanism in Tremellomycetes and some Rheb paralogs of Euglenozoa. Rheb evolution is thus surprisingly dynamic and presents a spectacular example of molecular tinkering.

All members of the order Trypanosomatida known to date are parasites that are most likely descendants of a free-living ancestor. Trypanosomatids are an excellent model to assess the transition from a free-living to a parasitic lifestyle, because a large amount of experimental data has been accumulated for well-studied members that are harmful to humans and livestock (Trypanosoma spp. and Leishmania spp.). However, recent advances in our understanding of the diversity of trypanosomatids and their close relatives (i.e., members of the class Kinetoplastea) have suggested that the change in lifestyle took place multiple times independently from that which gave rise to the extant trypanosomatid parasites. In the current study, transcriptomic data of two parasitic kinetoplastids belonging to orders other than Trypanosomatida, namely Azumiobodo hoyamushi (Neobodonida) and Trypanoplasma borreli (Parabodonida), were generated. We re-examined the transition from a free-living to a parasitic lifestyle in the evolution of kinetoplastids by combining (i) the relationship among the five orders in Kinetoplastea and (ii) that among free-living and parasitic species within the individual orders. The former relationship was inferred from a large-scale multigene alignment including the newly generated data from Azumiobodo and Trypanoplasma, as well as the data from another parasitic kinetoplastid, Perkinsela sp., deposited in GenBank; and the latter was inferred from a taxon-rich small subunit ribosomal DNA alignment. Finally, we discuss the potential value of parasitic kinetoplastids identified in Parabodonida and Neobodonida for studying the evolutionary process that turned a free-living species into a parasite.

Background & Aims: Management of patients with dysphagia, regurgitation, and related symptoms after antireflux surgery is challenging. This prospective, case-control study tested the hypothesis that compared with standard high-resolution manometry (HRM) with single water swallows (SWS), adding multiple water swallows (MWS) and a solid test meal increases diagnostic yield and clinical impact of physiological investigations., Methods: Fifty-seven symptomatic and 12 asymptomatic patients underwent HRM with SWS, MWS, and a solid test meal. Dysphagia and reflux were assessed by validated questionnaires. Diagnostic yield of standard and full HRM studies with 24-hour pH-impedance monitoring was compared. Pneumatic dilatation was performed for outlet obstruction on HRM studies. Clinical outcome was assessed by questionnaires and an analogue scale with "satisfactory" defined as at least 40% symptom improvement requiring no further treatment., Results: Postoperative esophagogastric junction pressure was similar in all groups. Abnormal esophagogastric junction morphology (double high pressure band) was more common in symptomatic than in control patients (13 of 57 vs 0 of 12, P = .004). Diagnostic yield of HRM was 11 (19%), 11 (19%), and 33 of 57 (58%), with SWS, MWS, and solids, respectively (P < .001); it was greatest for solids in patients with dysphagia (19 of 27, 70%). Outlet obstruction was present in 4 (7%), 11 (19%), and 15 of 57 patients (26%) with SWS, MWS, and solids, respectively (P < .009). No asymptomatic control had clinically relevant dysfunction on solid swallows. Dilatation was performed in 12 of 15 patients with outlet obstruction during the test meal. Symptom response was satisfactory, good, or excellent in 7 of 12 (58%) with no serious complications., Conclusions: The addition of MWS and a solid test meal increases the diagnostic yield of HRM studies in patients with symptoms after fundoplication and identifies additional patients with outlet obstruction who benefit from endoscopic dilatation., (Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background/aims: Supragastric belching (SGB) is a phenomenon during which air is sucked into the esophagus and then rapidly expelled through the mouth. Patients often complain of severely impaired quality of life. Our objective was to establish the prevalence of ex-cessive SGB within a high-volume gastrointestinal physiology unit, and evaluate its association with symptoms, esophageal mo-tility and gastresophageal reflux disease., Methods: We established normal values for SGB by analyzing 24-hour pH-impedance in 40 healthy asymptomatic volunteers. We searched 2950 consecutive patient reports from our upper GI Physiology Unit (from 2010-2013) for SGB. Symptoms were re-corded by a standardized questionnaire evaluating for reflux, dysphagia, and dyspepsia symptoms. We reviewed the predom-inant symptoms, 24-hour pH-impedance and high-resolution esophageal manometry results., Results: Excessive SGB was defined as > 13 per 24 hours. We identified 100 patients with excessive SGB. Ninety-five percent of these patients suffered from typical reflux symptoms, 86% reported excessive belching, and 65% reported dysphagia. Forty-one per-cent of patients with excessive SGB had pathological acid reflux. Compared to the patients with normal acid exposure these patients trended towards a higher number of SGB episodes. Forty-four percent of patients had esophageal hypomotility. Patients with hypomotility had a significantly higher frequency of SGB compared to those with normal motility (118.3 ± 106.1 vs 80.6 ± 75.7, P = 0.020)., Conclusions: Increased belching is rarely a symptom in isolation. Pathological acid exposure and hypomotility are associated with more SGB frequency. Whether SGB is a disordered response to other esophageal symptoms or their cause is unclear.

The development of the high-resolution esophageal manometry (HRM) and the Chicago classification have improved the diagnosis and management of esophageal motility disorders. However, some conditions have yet to be addressed by this classification. This review describes findings in HRM which are not included in the current Chicago classification based on the experience in our center. This includes the analysis of the upper esophageal sphincter, proximal esophagus, longitudinal muscle contraction, disorders related to gastroesophageal reflux disease and respiratory symptoms. The utility of provocative tests and the use of HRM in the evaluation of rumination syndrome and post-surgical patients will also be discussed. We believe that characterization of the manometric findings in these areas will eventually lead to incorporation of new criteria into the existing classification.

Stereotypical changes in pH occur along the gastrointestinal (GI) tract. Classically, there is an abrupt increase in pH on exit from the stomach, followed later by a sharp fall in pH, attributed to passage through the ileocecal region. However, the precise location of this latter pH change has never been conclusively substantiated. We aimed to determine the site of fall in pH using a dual-scintigraphic technique. On day 1, 13 healthy subjects underwent nasal intubation with a 3-m-long catheter, which was allowed to progress to the distal ileum. On day 2, subjects ingested a pH-sensitive wireless motility capsule labeled with 4 MBq (51)Chromium [EDTA]. The course of this, as it travelled through the GI tract, was assessed with a single-headed γ-camera using static and dynamic scans. Capsule progression was plotted relative to a background of 4 MBq ¹¹¹Indium [diethylenetriamine penta-acetic acid] administered through the catheter. Intraluminal pH, as recorded by the capsule, was monitored continuously, and position of the capsule relative to pH was established. A sharp fall in pH was recorded in all subjects; position of the capsule relative to this was accurately determined anatomically in 9/13 subjects. In these nine subjects, a pH drop of 1.5 ± 0.2 U, from 7.6 ± 0.05 to 6.1 ± 0.1 occurred a median of 7.5 min (1-16) after passage through the ileocecal valve; location was either in the cecum (n = 5), ascending colon (n = 2), or coincident with a move from the cecum to ascending colon (n = 2). This study provides conclusive evidence that the fall in pH seen within the ileocolonic region actually occurs in the proximal colon. This phenomenon can be used as a biomarker of transition between the small and large bowel and validates assessment of regional GI motility using capsule technology that incorporates pH measurement.