Gastrointestinal Motility Studies Research Articles

The Effect of Dexmedetomidine Sedation on Lower Gastrointestinal Motility in Children—Is It Suitable for Anorectal Manometry?

Anorectal manometry is one of the most frequently performed gastrointestinal motility studies in children. It is an important study in diagnosing Hirschsprung disease (HD). These procedures can be uncomfortable, painful and emotionally distressing. Nitrous oxide or midazolam are the only pharmacologic options available, as clinical experience suggests that they do not alter manometry readings. Our study was designed to determine whether Dexmedetomidine (DEX) could provide adequate sedation without disrupting anal and rectal pressure. The effect of DEX on anorectal function has never been studied in children. This prospective study recorded anorectal manometry (ARM) measurements prior to the administration of DEX and then repeated the measurements at 1 and 5 min after DEX. The main ARM measurements included resting intra-anal sphincter pressure (IASP) and the presence and characteristics of the recto-anal inhibitory reflex (RAIR). DEX was administered as a bolus followed by a continuous infusion. Twenty patients were included (60% female; mean age 10.8 ± 4.6 years). The RAIR became absent in 2/16 (12.5%) patients after DEX administration. DEX may alter physiologic ARM and IASP recordings necessary to diagnose gastrointestinal medical conditions.

Involvement of the autonomic nervous system in colonic contractions in conscious Suncus murinus.

Colonic motility is regulated by various factors along the gut-brain axis; however, detailed mechanisms are unknown. This study aimed to examine the involvement of the autonomic nervous system in colonic motility. Suncus murinus (suncus) is a small laboratory mammal suitable for gastrointestinal motility studies. Colonic motility and concomitant feeding and defecation behaviors in vagotomized and reserpine-administered suncus were recorded simultaneously for 24 h. Furthermore, we performed immunohistochemistry on tyrosine hydroxylase (TH) and insitu hybridization on corticotropin-releasing hormone (CRH) in suncus brain. Additionally, we examined c-Fos expression in the brain using immunohistochemistry in conscious suncus with colorectal distension. In vagotomized suncus, clustered giant migrating contractions (GMCs), consisting of strong contractions occurring in a short time, were observed, and the percentage of GMCs without defecation increased. The frequency of GMCs in the reserpine-administered suncus increased during a light period (ZT0-4, 4-8) and decreased during a dark period (ZT16-20, 20-24) compared to a vehicle group. Additionally, the percentage of GMCs without defecation in the reserpine-administered suncus increased. Suncus TH-immunopositive neurons were found in the locus coeruleus (LC), as shown in rodents. In contrast, CRH mRNA-expressing cells were not observed in a region assumed to be the Barrington's nucleus (Bar). Furthermore, colorectal distension in conscious suncus induced c-Fos expression in LC TH neurons. Our results suggest that the vagus and sympathetic nerves are not required for induction of GMCs invivo. However, they are likely to exert a modulatory role in control of GMC frequency in Suncus murinus.

Application of optogenetics in the study of gastrointestinal motility: A mini review

Disorders of gastrointestinal (GI) motility are associated with various symptoms such as nausea, vomiting, and constipation. However, the underlying causes of impaired GI motility remain unclear, which has led to variation in the efficacy of therapies to treat GI dysfunction. Optogenetics is a novel approach through which target cells can be precisely controlled by light and has shown great potential in GI motility research. Here, we summarized recent studies of GI motility patterns utilizing optogenetic devices and focused on the ability of opsins, which are genetically expressed in different types of cells in the gut, to regulate the excitability of target cells. We hope that our review of recent findings regarding optogenetic control of GI cells broadens the scope of application for optogenetics in GI motility studies.

Effect of ketamine, an NMDA-receptor antagonist, on gastric myoelectric activity in experimental pigs

Summary: Introduction: Preclinical studies in experimental pigs are carried out mostly under general anaesthesia. Ketamine is commonly used for induction of anaesthesia. However, there are concerns that ketamine, an NMDA-receptor antagonist, may influence gastric motor function. The aim of this study was to investigate porcine gastric myoelectric activity by means of electrogastrography (EGG). Methods: Seventeen female animals (mean weight 36.2±3.8 kg) were enrolled. Drugs used for induction of anaesthesia were: Group A (n=5): medetomidine 0.1 mg/kg i. m.; butorphanol 0.3 mg/kg i. m.; midazolam 0.3 mg/kg i. m.; Group B (n=6): azaperon 2.2 mg/kg i. m.; Group C (n=6): ketamine 20 mg/kg i. m.; azaperon 2.2 mg/kg i. m., followed in all groups by i.v. 1% propofol (repeated one-mL boluses, 10–12 mL in total). EGG recording started 15 min. after the induction administration and lasted 30 min. Results were evaluated as the dominant frequency of gastric slow waves (DF) and EGG power (areas of amplitudes). Results: In total, 510 one-minute EGG intervals were assessed. DFs were (mean ± standard deviation): 1.4±0.4 (Group A), 1.3±0.3 (Group B) and 0.2±0.1 cycles per min. (Group C). The differences between group C and groups A and B were statistically significant (p<0.001). Median power (IQR) was 0.13 (0.02–0.44; Group A), 0.13 (0.03–0.54; Group B) and 0.30 V2 (0.07–1.44; Group C). The difference between groups A and C was of borderline significance (p=0.066; type 2 error beta 0.295). Conclusions: Ketamine, administered even in a single intramuscular dose, affected myoelectric function of the porcine stomach. Therefore, it should be avoided in gastrointestinal motility studies in experimental pigs. Key words: ketamine – NMDA (N-methyl-D-aspartate) -receptor antagonist – electrogastrography – myoelectrical activity – experimental pigs

Investigating Defects of Esophageal Motility in Lung Transplant Recipients.

BackgroundLung transplant patients are at risk of developing chronic lung allograft dysfunction (CLAD) of which bronchitis obliterans syndrome (BOS) is the most common. These patients also are noted to develop gastrointestinal (GI) disease. Gastroesophageal reflux disease (GERD) is implicated in BOS, and diagnosis and treatment of GERD may help to decrease incidence of BOS.MethodsA total of 131 lung transplant recipients with post-transplant evaluation between 2012 and 2019 were studied. Of 60 post-transplant evaluations with at least 6 months of post-transplant follow-up that included impedance testing, high-resolution manometry (HRM), and pH testing, procedures were performed according to recognized standards.ResultsOf 60 patients, 56 (93%) were alive at 1-year post-transplant. The patients were found to have high rates of GI motility diseases: 37 patients (62%) had abnormal impedance testing, 50 patients (83%) had abnormal HRM results, 22 patients (37%) had abnormal pH test results. There was associated high rejection rates in patients with abnormal esophageal motility. There were 37 patients that had abnormal impedance test results and of those 25 patients (67%) developed rejection. Fifty patients had abnormal post-transplant HRM studies, 33 (66%) had an acute cellular rejection episode. Twenty-two patients had abnormal pH results, with 14 (63%) having an acute cellular rejection.ConclusionsPatients undergoing lung transplantation were found to have increased incidence of abnormal GI motility studies of the esophagus. These patients were further found to have increased rejection rates and BOS which has been associated with worsened mortality. Developing a formalized pre- and post-transplant motility study process, using evolving technologies for these patients, may provide guidance of at-risk patients for CLAD and early treatment to prevent CLAD.

Chemical profiles and pharmacological insights of Anisomeles indica Kuntze: An experimental chemico-biological interaction

Anisomeles indica (L.) Kuntze is an ethnomedicinally important plant that has long been used in traditional medicine to treat a variety of ailments, including dyspepsia, abdominal pain, colic, allergies, inflammation, and rheumatic arthritis. However, the scientific framework underlying these medicinal properties is not well known. This study aimed to investigate the antidepressive, antidiarrheal, thrombolytic, and anti-inflammatory potential of a methanol extract of A. indica (MeOH-AI). The potential bioactive compounds in the MeOH-AI were identified using gas chromatography-mass spectrometry (GC-MS), and antidepressant activities were evaluated using the tail suspension test (TST) and forced swim test (FST). Antidiarrheal effects were also assayed in castor oil-induced diarrhea and gastrointestinal motility studies. The anti-inflammatory activities were explored by examining the effects on protein inhibition and denaturation in heat- and hypotonic solution-induced hemolysis assays. The thrombolytic activity was evaluated using the clot lysis test in human blood. BIOVIA and Schrödinger Maestro (v11.1) were applied for docking analysis to determine binding interactions, and the absorption, distribution, metabolisms, excretion/toxicity (ADME/T) properties of bioactive compounds were explored using a web-based method. The GC-MS analysis of MeOH-AI revealed the presence of several bioactive compounds. MeOH-AI administration resulted in significant (p < 0.01) reductions in the immobility times for both the FST and TST compared with those in the control group. MeOH-AI also induced significant (p < 0.01) reductions in castor oil-induced diarrhea severity and gastrointestinal motility in a mouse model. In addition, the in vitro anti-inflammatory and thrombolytic activity studies produced remarkable responses. The binding assay showed that 4-dehydroxy-N-(4,5-methylenedioxy-2-nitrobenzylidene) tyramine interacts favorably with monoamine oxidase and serotonin and M3 muscarinic acetylcholine receptors, displaying good pharmacokinetic properties, which may mediate the effects of MeOH-AI on depression and diarrhea. Overall, the research findings indicated that MeOH-AI has significant antidepressant, antidiarrheal, and anti-inflammatory effects and may represent an alternative source of novel therapeutic factors.

Diabetic diarrhoea: A study on gastrointestinal motility, pH levels and autonomic function.

Chronic diarrhoea is a common, but poorly investigated diabetes complication. Autonomic neuropathy is a leading pathophysiological theory founded on old, small studies. Studies of gastrointestinal motility and pH levels are lacking. Using new diagnostic methods, we aimed to find out if diabetic diarrhoea was associated with alterations in gastrointestinal motility, pH levels and autonomic function. Fifty-seven patients (42 women, 46 with type 1 diabetes) were prospectively included. Symptoms were evaluated with the gastrointestinal symptom rating scale, defining ≥4 points as cases with diarrhoea. Patients scoring <4 were used as controls. We used the wireless motility capsule to measure gastrointestinal transit times, pH levels and contractility parameters. Autonomic function was assessed by measuring heart rate variability, baroreflex sensitivity and orthostatic hypotension. Seventeen patients (30%) had diarrhoea. Compared with controls, cases had slower gastric emptying (21:46 vs. 4:14, h:min, p = 0.03) and faster colonic transit (18:37 vs. 54:25, p < 0.001). Cases had increased intraluminal pH in the antrum (2.4 vs. 1.2, p = 0.009), caecum (7.3 vs. 6.4, p = 0.008) and entire colon (7.1 vs. 6.7, p = 0.05). They also had a decreased pH difference across the pylorus (3.3 vs. 4.9, p = 0.004) and ileocaecal junction (0.6 vs 1.0, p = 0.009). The groups did not differ in autonomic function, but diastolic blood pressure drop correlated rs = -0.34 (p = 0.04) with colonic transit time. Patients with diabetic diarrhoea had altered gastrointestinal transit and intraluminal pH levels, but minimal changes in autonomic function. Our results suggest that tests of gastrointestinal function are clinically useful in diabetic diarrhoea.

The basics of the study of gastrointestinal motility

The basics of the study of gastrointestinal motility

Hirschsprung disease and other gastrointestinal motility disorders in patients with CCHS.

Congenital central hypoventilation syndrome (CCHS) is an autonomic nervous system dysfunction due to PHOX2B gene mutation. Little is known about gastrointestinal motility disorders in CCHS patients. This study aims to describe the spectrum of gastrointestinal motility disorders in CCHS and provide PHOX2B genotype-phenotype correlation with Hirschsprung Disease (HD). We reviewed the records of 72 CCHS patients seen at Children's Hospital Los Angeles from 1999 to 2019. Data collected included demographics, PHOX2B genotype, ventilator dependence, medical and surgical history, and gastrointestinal motility studies. Of the 72 patients, 31% had HD, 50% females, and 60% had 20/27 PARM. Rectosigmoid HD formed 73% of the cases whereas long segment (up to splenic flexure involvement) forms represented 23%. Four patients had total colonic aganglionosis, including one patient with 20/25 PARM genotype. One HD patient was identified with colonic myopathy in the residual segment. One patient was found to have achalasia type 1.Conclusion: Nearly one third of our CCHS patients had HD. Although most had 20/27 PARM, 2 patients had 20/25 PARM. Thus, CCHS patients with constipation are at risk for HD regardless of genotype. Colonic myopathy may coexist in treated HD with refractory constipation. Achalasia may occur in patients with CCHS. What is Known: • Patients with CCHS have motility disorders and present with esophageal dysmotility and constipation as a manifestation of their autonomic nervous system dysfunction. • About 20% of patients with CCHS have Hirschsprung disease and previously described to be associated with NPARM and 20/27 PARM genotype. What is New: • Thirty-one percent of CCHS patients in our series have Hirschsprung disease (HD). •HD, including the more severe total colonic aganglionosis was found in a patient with 20/25 PARM genotype suggesting that CCHS patients withconstipation should be screened for HD regardless of genotype.

Translating the seminal findings of Carl Lüderitz: A description in English of his extraordinary studies of gastrointestinal motility accompanied by a historical view of peristalsis.

Carl Lüderitz provided the first comprehensive description of peristalsis in vivo in his publication from 1889 before Bayliss and Starling described the peristaltic reflex in isolated intestinal segments ex vivo 10years later. At that time, the peristaltic reflex, responsible for progression of intestinal content, was referred to as the Lüderitz-Bayliss-Starling reflex. This shows that his peers around 1900 were very well aware of the significant impact of Lüderitz´s papers. A major intention in this review is to bring the significant contributions by Dr. Carl Lüderitz (1854-1930) to the attention of our colleagues working in the field of Gastroenterology, in particular those interested in Neurogastroenterology and Gastrointestinal Motility. Until 1891, Carl Lüderitz published five more papers on the sensory and motor components of peristalsis including one seminal paper on stimulus-evoked muscle responses in the stomach in vivo. For most of his life, Carl Lüderitz was a practicing physician and doctor for the poor in Berlin. He spent a rather short time in academia, mostly during his studies in Jena under supervision of his cousin, the famous internist Hermann Nothnagel, and later in Berlin, where he volunteered for short periods at various university institutes but without any formal appointment. This paper is to honor Carl Lüderitz. We divided it into four chapters: a short biography, a summary and evaluation of his contributions, a translation of his seminal paper on peristalsis, and finally a historical view on peristalsis.

A simple automated approach to measure mouse whole gut transit.

Gastrointestinal (GI) motility is a complex physiological process that is critical for normal GI function. Disruption of GI motility frequently occurs in GI diseases or as side effects of therapeutics. Whole gut transit measurements, like carmine red leading-edge transit, in mice form the cornerstone of in vivo preclinical GI motility studies. We have developed an easily achievable, labor-saving method to measure whole gut transit time in mice. This approach uses inexpensive, commercially available materials to monitor pellet production over time via high definition cameras capturing time-lapse video for offline analysis. We describe the assembly of our automated gut transit setup and validate this approach by comparing the results with loperamide to delay transit and conventional transit measurements. We demonstrate that compared to the control group, the loperamide group had slowed transit, evidenced by a decrease in total pellet production and prolonged whole gut transit time. The control group had an extended transit time compared with the results reported in the literature. Whole gut transit rates accelerated to times comparable to the literature by disrupting cages every 10-15min to imitate the conventional approach, suggesting that disruption affects the assay and supports the use of an automated approach. A novel automated, inexpensive, and easily assembled whole gut transit setup is labor-saving and allows minimal disruption to animal behavior compared with the conventional approach.

Understanding gastrointestinal motility studies in pediatrics

Motility of the gut is affected by the nervous system, the endocrine system, smooth muscle cells, interstitial cells of Cajal, secretory mucosal cells, the immune system, and gut flora. Abnormal gastrointestinal motility can generate nonspecific symptom complaints that are refractory to standard treatment approaches. It is important to exclude anatomical obstruction or other causes for patients' symptoms prior to proceeding with motility evaluation. Motility studies that help to evaluate children with suspected motility problems include combined multichannel intraluminal impedance (MII) and pH recording, esophageal manometry, gastric emptying scinitigraphy, antroduodenal manometry, colonic manometry, and anorectal manometry. Many pediatric gastrointestinal motility evaluations should be completed in a pediatric motility center where specialized training is completed by physicians in this field. Indications for pediatric gastrointestinal motility studies and how the procedures are performed are addressed in this paper.

Constipation screening in people taking clozapine: A diagnostic accuracy study

ObjectiveClozapine is the favoured antipsychotic for treatment-refractory schizophrenia but its safe use requires careful adverse-effect management. Clozapine-induced gastrointestinal hypomotility (CIGH or ‘slow-gut’) is one of the most common and serious of clozapine's adverse effects. CIGH can lead to paralytic ileus, bowel obstruction, gastrointestinal ischaemia, toxic megacolon, and death. Enquiring about constipation is a simple and commonly used screening method for CIGH but its diagnostic accuracy has not previously been assessed. MethodsFirst, we examined the reliability of asking about constipation compared with asking about Rome constipation criteria in inpatients treated with clozapine (n = 69). Second, we examined the diagnostic accuracy of (1) self-reported constipation and (2) the Rome criteria, compared with the reference standard of gastrointestinal motility studies. ResultsAfter 30 motility tests, it was clear constipation screening had very poor diagnostic properties in this inpatient group and the study was terminated. Although 73% of participants had objective CIGH on motility testing, only 26% of participants self-reported constipation, with sensitivity of 18% (95% CI: 5–40%). Specificity and positive predictive values were higher (95% CI: 63–100% and 40–100%, respectively). Adding in Rome criteria improved sensitivity to 50% (95% CI: 28.2–71.8%), but half the cases were still missed, making this no more accurate than tossing a coin. ConclusionsCIGH is often silent, with self-reported constipation having low sensitivity in its diagnosis. Treating CIGH based on self-reported symptoms questions will miss most cases. However, universal bowel motility studies are impractical. In the interests of patient safety, prophylactic laxatives are suggested for people taking clozapine.

Chemical Characterization, Gastrointestinal Motility and Sensory Evaluation of Dark Chocolate: A Nutraceutical Boosting Consumers' Health.

We performed a comprehensive study encompassing chemical characterization and sensory evaluation of two types of dark chocolate, i.e., artisanal (Choco-A) and industrial (Choco-I), as well as an evaluation of onset of gastrointestinal symptoms and gastrointestinal motility in healthy subjects fed with dark chocolate. Proteomic, lipid and metabolite analysis were performed by LC-MS/MS analysis and the total phenol content and antioxidant activity were estimated in both types of chocolate. Fifty healthy volunteers joined the study of the sensory characteristics of both types of chocolate; another 16 subjects underwent the study of gallbladder and gastric emptying by functional ultrasonography and orocecal transit time by lactulose H2-breath test after ingestion of dark chocolate. Identification of polyphenols, amino acids and fatty acids was carried out in both types of chocolate analysed, and results confirmed their richness in polyphenols, amino acid derivatives and fatty acids (FAs) either saturated (stearic, myristic, palmitic, ecosanoic) or unsaturated (oleic and linolenic). For agreeability, Choco-A scored higher than Choco-I for smell, texture, and taste and they did not show significant differences in the gastrointestinal motility. In conclusion as for gastrointestinal motility studies, we report that the ingestion of a small amount of chocolate induced a mild gallbladder, gastric contraction and a fast transit time compared to the test meal in healthy subjects.

The pig as an animal model in biomedical research: A review

The advances in translational biomedical research, especially in genetic engineering, created new opportunities to trace the courses of human diseases and develop effective therapeutic methods. There remains, however, a growing demand for appropriate animal models for the precise evaluation of the efficacy and safety of new drugs or therapeutic concepts. Thus far, rodent models have been most widely used in translational research; however, since they do not perfectly reflect the human disease phenotype, transgenic pigs are increasingly being utilized as animal models. Thanks to the anatomical and physiological similarities between pigs and humans, swine are considered to be one of the most valuable animal models used in preclinical studies, including nutritional, metabolic and cardiovascular research. The resemblances involve the gastrointestinal, cardiovascular, urinary, respiratory, skeletal muscle and immune systems, as wells as body size, body composition and the omnivorous food choice. In addition, pigs are characterized by high fertility and fecundity, as well as the ease of use and low maintenance costs. Importantly, the existing efficient genetic engineering techniques enable relatively easy generation of tailored porcine models of human disease. One should be aware, however, of some physiological differences between humans and pigs to correctly interpret induced toxicological changes. The article provides an overview of current techniques for genetic modification of pigs, as well as the use of swine models in translational research exemplified by xenotransplantation, metabolic and coronary heart disease, and the gastrointestinal motility studies.

Nuclear Scintigraphy in Practice: Gastrointestinal Motility.

The purpose of this article is to describe the clinical utility of state-of-theart gastrointestinal transit scintigraphy, including the standardized esophageal transit, solid and liquid gastric emptying, small-bowel transit, colon transit, and whole-gut transit scintigraphy, with an emphasis on procedure performance. Radionuclide gastrointestinal motility studies are noninvasive, quantitative, and physiologic diagnostic tools for evaluating patients with gastrointestinal complaints.

Evaluation of postural tachycardia syndrome (POTS).

The diagnostic evaluation of a patient with suspected postural tachycardia syndrome (POTS) requires a thoughtful diagnostic approach utilizing a careful clinical history and examination, laboratory, and autonomic testing. This article outlines the importance of a thorough history in identifying mechanism of symptom onset, clinical features, associated clinical conditions or disorders, and factors that may result in symptom exacerbation. The clinical examination involves an assessment of pupillary responses, an evaluation for sudomotor and vasomotor signs, and an assessment for joint hypermobility. Laboratory testing helps to exclude mimics of autonomic dysfunction, recognize conditions that may exacerbate symptoms, and to identify conditions that may cause or be associated with autonomic nervous system disease. The purpose of autonomic testing is to confirm a POTS diagnosis, exclude other causes of orthostatic intolerance, and may provide for characterization of POTS into neuropathic and hyperadrenergic subtypes. Other diagnostic studies, such as epidermal skin punch biopsy, exercise testing, radiographic studies, sleep studies, gastrointestinal motility studies, and urodynamic studies should be considered when clinically appropriate.

Antroduodenal Manometry Is Abnormal in Children Presenting With Orthostatic Intolerance and Gastrointestinal Symptoms.

Gastrointestinal (GI) symptoms of nausea, vomiting, and abdominal pain are common in patients with orthostatic intolerance (OI), including neurally mediated hypotension (NMH) and postural orthostatic tachycardia syndrome (POTS). Autonomic dysregulation is considered the underlying pathophysiology behind the cardiovascular symptoms of POTS. Because the autonomic nervous system also regulates GI motility, we hypothesized that patients with POTS and GI symptoms will have evidence of autonomic dysmotility of the upper GI tract. Thirty-five subjects with OI and GI symptoms were studied. All the subjects had a 24-hour antroduodenal manometry (ADM) study, in conjunction with pharmacologic challenge and autonomic and tilt table testing (TTT). The mean subject age was 16.2 ± 2.8 years (range 10-23.8 years), and male to female ratio was 10:25. TTT was abnormal in all the 35 subjects, whereas Valsalva testing was abnormal (+40 mmHG) in 21 of 34 (62%) subjects, and corrected QT interval was ≥0.44 seconds in 19 of 35 (54%) subjects. During TTT, GI symptoms were reproduced in 31 of 35 (89%) studies. ADM was found to be abnormal at baseline, before the TTT in 5 of 35 (14%) subjects, whereas it became abnormal in 23 of 34 (68%) subjects during TTT. In addition, the expected response to the pharmacologic challenge was limited. Overall, ADM was abnormal in 26 of 35 (74%) patients either at baseline or during TTT in these subjects with OI. ADM is frequently abnormal in children with OI and GI symptoms. Upper GI motility studies should be a part of the comprehensive evaluation in this population.

The effect of subthalamic deep brain stimulation on gastric motility in Parkinson's disease

ObjectiveDeep brain stimulation of the subthalamic nucleus (STN-DBS) is well established for treating the motor symptoms for advanced Parkinson's disease (PD) but its effects on gastric myoelectrical activity and gastrointestinal symptoms have not been well studied. The aim of this study was to evaluate the effect of STN-DBS on gastric motility using electrogastrography (EGG). MethodsTwenty patients with PD (5 females, 15 males; mean aged 58.0 ± 9.0 years) who underwent STN-DBS were studied. EGG was performed in fasting and postprandial conditions before STN-DBS and 3 months after the surgery. We also evaluated the frequency and severity of gastrointestinal symptoms based on a structured gastrointestinal dysfunction questionnaire. ResultsAfter STN-DBS the percentage of normogastria (47.8 ± 20.7 vs 51.3 ± 15.1) and period dominant power (PDP) (11.8 ± 1.2 vs 12.3 ± 0.9) significantly increased, the percentage of arrhythmia decreased compared to the baseline during fasting and postprandial state. Abnormal response to a meal (power ratio of PDP <1 after meal) decreased from 70% to 55% after 3 months follow-up. The abnormal EGG (the percentage of normogastria <70%) decreased in both fasting (from 80% to 65% patients) and postprandial state (from 80% to 60% patients), respectively after the surgery. The most common GI symptoms reported prior to the surgery were constipation 95%, difficulty with defecation 85% and dysphagia 50%. After STN-DBS all gastrointestinal symptoms improved, the greatest improvement was observed in difficulty with defecation. ConclusionOur results suggest that STN-DBS improves gastric motility as well as gastrointestinal symptoms in PD. Further studies of gastrointestinal motility in PD are warranted.

Introducing our Associates

We are writing to you with one calendar year under our belt as the editors of Neurogastroenterology and Motility, and we are pleased to report the journal is strong, and it is an increasingly popular target journal for investigators in our field. In 2012, we handled 439 manuscripts, which is a robust 17% increase over the 2011 submissions, and represents a 50% increase in manuscript submissions in just 5 years. The impact factor continues to trend upward. It is currently 3.414, up from 3.349 the year before. This is noteworthy development because the number of articles published in the journal was increased in 2010 at the risk of a negative effect on the impact factor. To maintain the quality of the publications while continuing to publish our articles with a short lag time, the rejection rate has increased from roughly 41% to 47% of the submitted manuscripts. The average time between submission and publication is 8 weeks with accelerated time lines for clinical trials. The successful operation of our journal is highly dependent on the magnanimous services of our peer reviewers. In 2012, 364 members of the Neurogastroenterology and Motility community donated their time and expertise by participating in the rigorous review process and suggesting areas of improvement for the authors to strengthen and revise the manuscript that we accepted for publication. We thank all of you who have provided these services, and we would like to call special attention to the following 12 individuals who reviewed the most manuscripts, and did so with an average turnaround time of 11.4 days: Pieter Janssen, Pere Clave, Mark Fox, Sabine Roman, Michael Camilleri, Albert Bredenoord, Shin Fukudo, Purna Kashyap, David Linden, Bridget Southwell, Yvette Taché, and Heather Young. In an effort to further increase the service we provide to authors and deal with the increased workload that has accompanied the increase in manuscript submissions, we have added two Associate Editor positions to the editorial board structure. We are pleased to announce that Drs. Sylvie Bradesi (Basic Science) and Arjan J. Bredenoord (Clinical) are the two new Associate Editors. Dr Bradesi received her PhD in Biological Sciences at the Paul Sabatier University in Toulouse, France and pursued her postdoctoral training in Gastroenterology and Physiopathology of Visceral Pain under the mentorship of Dr Emeran Mayer at the Center for Neurovisceral Sciences and Women's Health at UCLA, Los Angeles. She is now at the Center for Neurobiology of Stress at UCLA, School of Medicine, Division of Digestive Diseases. She has developed a research program with a strong interest in the development of animal models for functional bowel disorders, investigating the physiopathology of visceral hyperalgesia and the functional role of CNS glial cells in pain facilitation and increased stress responsiveness. Albert J. (Arjan) Bredenoord graduated in Medicine at Antwerp University, Medicine at Antwerp University, Belgium where he performed translational studies of gastrointestinal motility. He subsequently worked on several clinical research GI motility projects at the Mayo Clinic, Rochester, USA, and at the University of Utrecht, the Netherlands, for which he earned a PhD. His clinical training was performed in Nieuwegein, the Netherlands, and at the Royal London Hospital in London, UK. He currently works at the Amsterdam Medical Center where he is dedicated to patients care, scientific research, and education. His primary expertise is on gastrointestinal motility of the esophagus. Another important announcement is that the journal is going entirely electronic as of January, 2014. Reprints of individual articles will be available but hard copies will no longer be published. The percentage of authors who ask for their article to be published in the hard copy version of the journal has decreased significantly in the past 2 years making the article version no longer a true representation of what Neurogastrenterology and Motility has to offer. In preparation for this transition, we encourage anyone who has not done so to register to receive the electronic Table of Contents via email. To do so, you will have to register for the Wiley Online Library and indicate that you wish to receive the Table of Contents for our journal. You can do this from the journal website. In conclusion, we thank you for your societies' support of the journal and look forward to another banner year for the journal.