Esophageal Muscle Research Articles

Esophageal manifestation in patients with scleroderma.

The esophagus is the most commonly affected part of the gastrointestinal system in patients with systemic sclerosis (SSc). Esophageal involvement may lead to a significant reduction in patient quality of life. The exact pathophysiology is complex and not yet fully elucidated. Ultimately, esophageal smooth muscle becomes atrophied and replaced by fibrous tissue leading to severe motility disturbance of the distal esophagus. Symptoms are mainly attributed to gastroesophageal reflux disease and to esophageal dysmotility. Compelling evidence has correlated esophageal involvement to the severity of pulmonary disease. No formed guidelines exist about the diagnostic modalities used to assess esophageal disease in patients with SSc, though upper gastrointestinal endoscopy is the first and most important modality used as it can reveal alterations commonly observed in patients with SSc. Further exploration can be made by high resolution manometry and pH-impedance study. Proton pump inhibitors remain the mainstay of treatment, while prokinetic agents are commonly used as add-on therapy in patients with symptoms attributed to gastroesophageal reflux disease not responding to standard therapy as well as to motility disturbances. Gastroesophageal reflux disease symptoms in patients with SSc are frequently difficult to manage, and new therapeutic modalities are emerging. The role of surgical treatment is restricted and should only be preserved for resistant cases.

New data on distribution of muscle and serotonin-containing cells in larvae of diadematid sea urchins from Nha Trang Bay (South China Sea)

ABSTRACT With staining by antibodies, the general morphology and topography of serotonin-containing cells (SCC) and cells expressing high levels of actin have been compared between three developmental stages in ‘Echinopluteus transversus’ type larvae of sea urchins from genus Diadema. At an early pluteus stage single SC cells are found in the preoral buccal lobe of the pluteus as a component of the ciliary band. The cells expressing high levels of actin form the oesophageal muscles. At the middle pluteus stage, SC cells form two ganglion-shaped clusters in the anterior part of the larva, as well as a distributed neuropil running along the ciliary band; the bodies of the SC cells are included in the ciliary band epithelium. At this developmental stage the oesophageal musculature and little dilator muscles at the mouth were visualized. In late pluteus stage, the ganglion-shaped groups of SC cells merge into one in the anterior part of the larva; the distributed neuropil in the ciliary band is preserved. At this developmental stage, the cells expressing high levels of actin are in the oesophagus muscles and in three separate well developed muscles: ventral adductor muscle, dorsal adductor muscle, and abductor muscle. These muscles carry out movements of the larval arms.

Morphological and molecular characterization of Sarcocystis cameli and Sarcocystis ippeni from the muscles of One-Humped Camel (Camelus dromedarius ) in New valley Governorate, Egypt.

Sarcocystis spp. are cysts-forming coccidian parasites which infect several animals including camels as intermediate hosts. The present study was designed to study the Sarcocystis infection in camels (Camelus dromedaries) at morphological and molecular levels. Sample of the esophageal, heart and ocular muscles tissue were collected from infected camels from El-kharga (New valley Governorate) and examined for Sarcocystis spp. using macroscopic evaluation, light microscopy (LM), transmission electron microscopy (TEM) and molecular analysis. Two species Sarcocystis cameli and Sarcocystis ippeni were recognized. Sarcocysts were thin walled with barely visible projections. Using the TEM, the two structurally distinct sarcocysts were recognized by unique villar protrusions (Vp). Sarcocysts of S. cameli had Vp of type 9j. The sarcocyst wall had upright slender Vp, up to 0.1-0.4 μm long and 0•05-0.1 μm wide. On each Vp, Rows of knob-like protrusions are present appeared to be interconnected. Sarcocystis ippeni had ‘‘type 32’’ sarcocyst wall characterized by conical Vp with an electron dense knob. The Vp were approximately 175.27-266.76 nm long, 100.45-175.98 nm wide. In each Sarcocystis, the Vp had microtubules (Mt) that originated at midpoint of the ground substance (Gs) and continued up to the tip. Molecular data revealed the amplification of partial fragments of the 18S rRNA gene (~600 bp). The digestion analysis of obtained PCR products using RFLP method utilizing (Mbo1) appeared 2 bands approximately 250, 350 bp for each Sarcocystis. Molecular analysis demonstared the ability of 18S rRNA gene for distinguishing Sarcocystis species in studied animals and to be used as molecular marker.

Three-Dimensional Printed Design of Antibiotic-Releasing Esophageal Patches for Antimicrobial Activity Prevention.

Pharyngoesophageal defects can cause exposure to various bacterial flora and severe inflammation. We fabricated a biodegradable polycaprolactone (PCL) patch composed of both thin film and three-dimensional (3D) printed lattice, and then investigated the efficacy of pharyngoesophageal reconstruction by using 3D printed antibiotic-releasing PCL patches that inhibited early inflammation by sustained tetracycline (TCN) release from both thin PCL films and printed rods implanted in esophageal partial defects. PCL was 3D printed in lattice form on a presolution casted PCL thin film at ∼100 μm resolution. TCN was loaded onto the PCL-printed patches by 3D printing a mixture of TCN and PCL particles melted at 100°C. TCN exhibited sustained release in vitro for over 1 month. After loading TCN, the patches showed decreased tensile strength and Young's modulus, and less than 20% TCN was slowly released from the 2.5% TCN-loaded PCL patches over 150 days. Cytotoxicity tests of extract solutions from patch samples demonstrated excellent in vitro cell compatibility. Antibiotic-releasing PCL patches were then transplanted into partial esophageal defects in rats. Microcomputed tomography analysis revealed no leak of orally injected contrast agent in the entire esophagus. Tissue remodeling was examined through histological responses of M1 and M2 macrophages. In particular, the 1% and 3% TCN patch groups exhibited significant muscle layer regeneration by desmin immunostaining. Further histological and immunofluorescence analyses revealed that the 1% and 3% TCN patch groups exhibited the best esophageal regeneration according to reepithelialization, neovascularization, and elastin texture around the implanted sites. Our antibiotic-releasing patch successfully consolidates the regenerative potential of esophageal muscle and mucosa and the antibacterial activity of TCN for 3D esophageal reconstruction. Impact statement Anastomosis site leakage and necrosis after pharyngoesophageal transplantation inevitably causes mortality because the mediastinum and neck compartments become contaminated. Herein, we present antibiotic-releasing pharyngoesophageal patch that prevents saliva leakage and has an antimicrobial effect. We have demonstrated antibiotic release profile and mechanical properties for esophageal transplantation. Upon esophageal transplantation of antibiotic-releasing polycaprolactone patches, antimicrobial effects and muscle regeneration around the graft sites were clearly identified in the group containing 1% and 3% of tetracycline. The esophageal graft led to the remarkable recovery throughout reepithelialization, neovascularization, and elastin texture of around the implanted sites. We believe that current system is capable of various applications that require antibacterial in vivo.

3D biomechanical properties of the layered esophagus: Fung-type SEF and new constitutive model.

Most current studies on the passive biomechanical properties of esophageal tissues directly use the exponential strain energy function (SEF) to fit and calculate the constants of the constitutive equation. In the context of the extensive application of exponential SEF, in-depth research on the exponential SEF is still lacking. The purpose of this study is to combine the exponential function with the polynomial SEF to obtain the most suitable constitutive equation to describe the three-dimensional passive behavior of the esophagus. fresh pig esophagus with a length of 13cm in the middle position was selected as esophageal samples. The esophageal sample was separated into muscular layer and mucosal layer with surgical scissors. Stretch-inflation mechanical tests of the intact esophagus, esophageal muscular, and esophageal mucosa were carried out on a triaxial test machine. The external radius, axial force, and internal pressure were recorded simultaneously. The seven-parameter Fung-type SEF and several new SEFs combining polynomials and exponents were used to fit the experimental data curves. The stretch-inflation test data and the morphometric parameters at the zero-stress state of the layered esophagus were obtained. The new SEF with polynomial and exponential combination is more suitable to describe describing the three-dimensional passive biomechanical properties of esophageal tissue. Among them, New-Fung13 SEF is more suitable for describing the passive biomechanical properties of intact esophageal tissue, Sokolis-Fung13 SEF is more suitable for the esophageal muscle layer, and New-Fung10 SEF is more suitable for the esophageal mucosa. The constitutive parameters of the optimal constitutive model for each layer of the esophagus were obtained.

Management of Ineffective Esophageal Hypomotility.

Esophageal hypomotility in general and especially ineffective esophageal motility according to the Chicago criteria of primary motility disorders of the esophagus, is one of the most frequently diagnosed motility disorders on high resolution manometry and results in a large number of patients visiting gastroenterologists. Most patients with esophageal hypomotility present with gastroesophageal reflux symptoms or dysphagia. The clinical relevance of the motility pattern, however, is not well established but seems to be correlated with disease severity in reflux patients. The correlation with dysphagia is less clear. Prokinetic agents are commonly prescribed as first line pharmacologic intervention to target esophageal smooth muscle contractility and improve esophageal motor functions. However, the beneficial effects of these medications are limited and only confined to some specific drugs. Serotonergic agents, including buspirone, mosapride and prucalopride have been shown to improve parameters of esophageal motility although the effect on symptoms is less clear. Understanding on the complex correlation between esophageal hypomotility and esophageal symptoms as well as the limited evidence of prokinetic agents is necessary for physicians to appropriately manage patients with Ineffective Esophageal Motility (IEM).

Calcitonin Non-Secreting Mixed Medullary-Papillary Thyroid Carcinoma: Report of a Rare Entity and Therapeutic Implications

Background: Medullary thyroid carcinoma (MTC) is a relatively rare and aggressive form of thyroid malignancy arising from parafollicular cells. The biochemical hallmark of MTC is elevated serum calcitonin (CTN), which aids initial diagnosis and disease surveillance. An atypical form of calcitonin non-secreting MTC has been previously described, with just over 50 cases published in the literature. This case report of a true mixed medullary-papillary thyroid carcinoma with a non-secretory medullary component is exceptionally rare. Clinical Case: A 67-year-old male presented with new-onset hoarseness and was found to have a 4 cm thyroid nodule replacing the right lobe with associated ipsilateral cord paralysis and ipsilateral cervical lymphadenopathy. The patient had no family history of endocrinopathies. A diagnosis of MTC was rendered at core-needle biopsy, based on the characteristic morphological findings and positive immunohistochemistry (IHC) for calcitonin (CTN) and CEA. Cervico-thoracic CT demonstrated tracheal and esophageal involvement by the tumor. The serum CEA was 8.7 pg/ml [0-5]; however, serum CTN was undetectable < 2 pg/ml [2-8.2]. The patient subsequently underwent a total thyroidectomy with bilateral central neck dissection and right lateral neck dissection. Excision of the tumor necessitated the dissection of involved esophageal muscle from mucosa and removal of four tracheal rings with part of the cricoid. The surgical specimen demonstrated a single 3.6 cm tumor in the right thyroid lobe composed of medullary and papillary intermixed neoplastic cells (mixed MTC-PTC) with predominant medullary component and gross extrathyroidal extension. Positive IHC for calcitonin, CEA, and thyroglobulin confirmed the diagnosis. Out of ninety resected lymph nodes in total, five nodes were involved with medullary carcinoma (with extranodal extension), and three had papillary carcinoma micrometastases. Postoperatively, the patient underwent adjuvant external beam radiation to the surgical bed. At four-month follow-up, CEA levels were 1.4 pg/ml [0-5], TSH 0.04 µIU/ml [0.35-4.9] and thyroglobulin (Tg) with Tg Ab levels were undetectable. The patient continues close surveillance. Conclusion: Calcitonin non-secreting MTC management is challenging due to the lack of a reliable biomarker that aids initial diagnosis, surveillance, and prognostic stratification. Whether a rare form of non-secretory MTC represents a more aggressive variant is yet to be determined. The prognosis of patients with mixed MTC-PTC tumors appears to be driven by the medullary component that prioritizes the optimal surgical approach and further management.

IL‐13/IL4Rα Signaling Increases Tension in Human Circular and Longitudinal Esophageal Smooth Muscle Through Distinct Molecular Pathways: Potential Contribution to Reduced Esophageal Distensibility in EoE

Introduction Reduced esophageal distensibility (ED) in EoE has been attributed largely to fibrosis, but inflammatory cell infiltration and increased tension in esophageal smooth muscle (ESM) also might contribute to reduced ED. EoE is a type 2 immune disease in which type 2 cytokines IL-4 and IL-13 signal through the IL-4 receptor alpha (IL4Rα), activating Janus kinases (JAKs) that in turn activate STAT6. Dupilumab, a monoclonal antibody against IL4Rα, can improve ED in EoE patients, but it is unclear whether this is due to effects on fibrosis, inflammatory cells, or ESM tension. To explore how IL4Rα signaling might affect ESM tension, we treated ESM cells with IL-13 and selective inhibitors of STAT6 (AS1517499, 600 nM) or JAK1/2 (ruxolitinib, 100 ng/ml). Since ESM tension is induced by phosphorylation of myosin light chains through PKC and ROCK pathways, we also studied effects of selective inhibitors of PKC (calphostin C, 500 nM) and ROCK (Y-27632, 10 µM) on ESM tension. Methods Using 1 circular (C) and 1 longitudinal (L) telomerase-expressing ESM cell lines generated from muscularis propria of a human organ donor, cell contraction was assessed in the attached gel contraction model. Gels containing equal numbers of ESM cells were cultured for 48 hours with and without IL-13 (50 ng/ml), during which ESM tension developed; contraction was initiated by releasing the gel from the sides of the culture plate. Histamine (100 µM), a contraction mediator, was added immediately prior to release in some studies. Contraction was assessed by measuring gel surface area over 24 hours using Image J. Gel contraction studies were repeated in the presence of pathway inhibitors. Results In non-treated cells, gel sizes of CESM were significant smaller at all time points than those of LESM (p<0.001). Compared to non-treated controls, IL-13 significantly reduced gel size in both CESM and LESM (Figures 1&2). Also compared to non-treated controls, IL-13-treatment resulted in smaller gel sizes at all time points following histamine stimulation in both CESM and LESM (p<0.05). In LESM, IL-13-induced reductions in gel size were significantly inhibited by ruxolitinib, calphostin C, and Y-27632, but not by AS1517499 (Figure 2). In CESM, these IL-13-induced reductions were significantly inhibited by ruxolitinib and calphostin C, but not by Y-27632 or AS1517499 (Figure 1). Conclusions CESM generates more baseline tension that LESM. IL-13 increases tension and enhances the contractile response to histamine in both CESM and LESM. In LESM, both the PKC and ROCK pathways contribute to IL-13-mediated increases in tension whereas in CESM, only the PKC pathway contributes to this effect. These findings demonstrate distinct molecular pathways whereby IL-13 contributes to LESM and CESM tension, and suggest that IL-13-induced ESM tension may contribute to the reduced ED of EoE.

Control of Heart Rate by Nucleus Ambiguus Cardiovagal Neurons

Heart rate is a well-established indicator of overall health and well-being, yet little is known about the neurons that control it. Although the heart has its own pacemaker, heart rate is largely regulated by the interplay between sympathetic activities (via sympathoexcitatory neurons) and parasympathetic activities (via cardiac vagal preganglionic neurons (CVNs)). The nucleus ambiguus (nAmb), a region in the medullary reticular formation of the brainstem, is a major center of parasympathetic cardiac control and houses the majority of CVNs, along with other neurons that control respiratory functions (bronchoconstriction, bronchosecretion) and upper airway and esophageal muscles. Because of the diversity of neuron types in the nAmb, it is challenging to isolate CVNs for study, which greatly limits what we know about their gene expression, synaptic circuitry, and specific roles in cardiac function. To address these issues, we characterized cardiovagal neurons based on transcriptome-wide mRNA expression, synaptic circuitry, and sufficiency for heart rate control. Our single-cell transcriptomics analysis of 235 nAmb neurons pointed to three molecularly distinct neuron subtypes (marked by the genes Crhr2, Vipr2, and Tbx3) in the nAmb, which we validated and anatomically mapped by in situ detection of marker transcripts. We then used marker-driven genetic technology to fluorescently label the axon projections of Tbx3 nAmb neurons and imaged them in optically cleared heart samples. Our results show that these neurons innervate multiple sites in the atria and ventricles, consistent with multiple roles in cardiac function. Similar synaptic circuitry studies of the Crhr2 nAmb and Vipr2 nAmb neurons showed that they innervate the esophagus and larynx, respectively, but do not innervate the heart. Furthermore, using an intersectional optogenetics approach to specifically manipulate the activity of nAmb neuron subtypes in vivo, we have shown that activating the Tbx3 nAmb neurons in both freely behaving and anesthetized mice dramatically and immediately decreases heart rate (from 430 bpm to 160 bpm) as determined via EKG readings, whereas activating other subtypes of nAmb neurons did not affect heart rate. This effect on heart rate was abolished by administration of atropine, a muscarinic receptor antagonist. Together, these studies not only highlight the impact of Tbx3 nAmb neurons on heart rate, but also reveal a distinct molecular, anatomical, and functional organization within the nAmb.

The possible correlation between the chronic esophageal achalasia and periodontal disease - a pilot study.

Achalasia is a very rare disease characterized by the lack of motor coordination in various phases of contraction-relaxation of esophageal muscles. The aim of the study is to determine the correlation between esophageal achalasia and oral diseases. Thirteen esophageal achalasia patients were assessed for the presence of any potential oral symptoms through a questionnaire. 5 volunteered to be included in the study. The oral health status of these 5 patients was assessed by a clinical oral examination. The oral health status of the included cases was compared to the oral health status data from a published observational study on healthy individuals belonging to the same (Italian) population. Our results show that the number of periodontal pockets with Probing Pocket Dept > 4 mm is significantly increased, compared to the average of the Italian population; the Bleeding On Probing (BOP) is not related to the Plaque Control Record (PCR); so we can say that the value of periodontal index is not correlated with the value of oral hygiene index. Considering the limitations of a research based on small numbers, it nevertheless seems advisable to assert that there is a correlation between esophageal achalasia and periodontal disease.

High-Resolution Esophageal Manometry in Clinical Practice – An Indian Perspective

High-resolution esophageal manometry (HREM) is a technique to determine the function of esophageal musculature and the integrity of the lower esophageal sphincter. This test is commonly used for evaluation of nonobstructive dysphagia, assessment of peristaltic reserve before anti-reflux surgery, symptoms of regurgitation, and noncardiac chest pain unexplained by endoscopic evaluation. The current review deals with the spectrum of esophageal motility disorders in India and reviews the technique and reporting of HREM. The clinical utility of HREM in Indian setting with special reference to challenges faced has been discussed in detail.

Endoscopic tunneling procedures in achalasia and gastroparesis

Since the first publication of peroral endoscopic myotomy (POEM) by Haruhiro Inoue et al. in 2008 in Japan, various novel endoscopic procedures have been established, which are performed after iatrogenic creation of a submucosal tunnel as a "new space" 1. Through the artificially formed access in the tela submucosa, interventions in the muscular layer of the esophagus and stomach can be performed while carefully sparing the mucosal layer 2. These include, peroral myotomy of the esophageal muscle layer in patients with achalasia (POEM) and myotomy of the pylorus in patients with gastroparesis (antropyloromyotomy, G-POEM). Further indications include splitting of Zenker diverticulum in POEM technique ("Z-POEM") as well as the removal of subepithelial tumors (STER: submucosal tunneling, endoscopic resection). The long-term therapeutic success (with > 80 % response) of these innovative procedures has now been proven by controlled studies, especially in achalasia 2 3 4 5 6.

Transcervical Transtracheal Resection of Cervical Esophageal Smooth Muscle Tumor

Cervical esophageal smooth muscle tumours are traditionally resected via lateral trans-cervical +/- video-assisted thoracoscopic approaches. However exposure is frequently limited with risks of recurrent laryngeal nerve and posterior tracheal wall injury, and jeopardization of cervical tracheal and cervical esophageal blood supply. We herein describe an anterior trans-cervical trans-tracheal approach to counter some of the aforementioned problems and avoid morbidities associated with thoracoscopic surgery when resecting smooth muscle tumors arising from the cervical esophagus.

Mechanics informed fluoroscopy of esophageal transport.

Fluoroscopy is a radiographic procedure for evaluating esophageal disorders such as achalasia, dysphasia and gastroesophageal reflux disease. It performs dynamic imaging of the swallowing process and provides anatomical detail and a qualitative idea of how well swallowed fluid is transported through the esophagus. In this work, we present a method called mechanics informed fluoroscopy (FluoroMech) that derives patient-specific quantitative information about esophageal function. FluoroMech uses a convolutional neural network to perform segmentation of image sequences generated from the fluoroscopy, and the segmented images become input to a one-dimensional model that predicts the flow rate and pressure distribution in fluid transported through the esophagus. We have extended this model to identify and estimate potential physiomarkers such as esophageal wall stiffness and active relaxation ahead of the peristaltic wave in the esophageal musculature. FluoroMech requires minimal computational time and hence can potentially be applied clinically in the diagnosis of esophageal disorders.

Histological observations on the development of digestive tract in &amp;lt;italic&amp;gt;Tachypleus tridentatus&amp;lt;/italic&amp;gt;

In this study, paraffin sections and H-E staining were used to study the individual development of alimentary canal of <italic>T</italic>. <italic>tridentatus</italic> at 15 days old, 30 days old, 60 days old, the second instar and adult. Results showed that the structure of digestive tract of <italic>T</italic>. <italic>tridentatus</italic> at 15 days old was not clearly distinguished. The esophagus, stomach, midgut and rectum were similar in structure. Only mucous membrane was clear, and mucous folds were relatively short. When <italic>T</italic>. <italic>tridentatus</italic> was 30 days old, the mucous epithelium of esophagus and stomach showed dark bands, the muscle fibers of esophagus extended in a ring, and the muscle bundles of stomach were thickened. The mucous epithelium of the middle intestine and rectum had a striate border at the top, and the muscular fiber bundles were thickened. When <italic>T</italic>. <italic>tridentatus</italic> was 60 days old, the dark bands at the top of the mucosa epithelium of the esophagus and stomach developed into striate margins, with increased esophageal muscle fibers and thickened gastric myofilament bundles. The mucosa fold of the midgut and rectum increased in height and number, and the pigmentation of the striate border deepened. The digestive tract of the second instar <italic>T</italic>. <italic>tridentatus</italic> was composed of mucous layer, submucous , muscle layer and serosal layer, and the tissue structure was basically well-developed. With the gradual improvement of tissue structure, the number of folds of esophagus and gastric mucosa increased significantly to 9-15, and the striate border at the top of the mucosal epithelium developed into chitin layer. The number of folds in the mucosa of the middle intestine and rectum increased rapidly to 10-12, and the epithelial striatum of the mucosa of the middle intestine thickened, with little tin layer, and the epithelial striatum of the rectum developed into chitin layer. The structure of digestive tract of adult <italic>T</italic>. <italic>tridentatus</italic> was complete, and the mucous layer, submucous layer, muscle layer and serous membrane of digestive tract were obviously thicker than that of early stage. Results showed that the tissue structure of the alimentary canal of <italic>T</italic>. <italic>tridentatus</italic> was basically developed at the second instar, and the tissue structure of each layer was thickened with age, which was suitable for its living habit.

Simultaneous Examination of Eosinophil Infiltration in Esophageal Mucosa and Muscle in Patients with Achalasia: Direct Biopsy of the Esophageal Muscle at Per-oral Endoscopic Myotomy.

BackgroundThe relationship between eosinophilic esophagitis (EoE) and achalasia is not completely understood. There have been reports of eosinophilic infiltration of all esophageal layers in patients with achalasia. However, a routine endoscopic biopsy of the muscular layer is usually not feasible. We evaluate the safety and efficacy of muscle layer biopsy during per-oral endoscopic myotomy (POEM) as well as the prevalence of eosinophilic infiltration of the esophageal mucosa and muscular layer in patients with achalasia.Patients and MethodsAll enrolled patients had diagnosed achalasia and had simultaneous biopsies of the muscular layer at the middle esophagus and distal esophageal sphincter as well as the mucosal layer of the proximal and distal esophagus during POEM. All POEM procedures took place from August 2018 to December 2018 or September 2019 to November 2019. Various demographic, disease-related, and procedure-related data were collected from chart review. Eosinophilic infiltration in the biopsy specimen was examined.Key ResultsTwenty consecutive patients (65% female, age range: 21–84) with a pre-procedure Eckardt score of >6 were enrolled during the study period, with the duration of their achalasia ranging from 1 to 32 years. Eighteen patients had clinical symptomatic improvement after POEM, as defined by an Eckardt score <3. Endoscopic examination did not reveal any signs of eosinophilic esophagitis. Pathologic examination of biopsies revealed eosinophilic infiltration in three of 20 patients (15%) in the distal esophageal mucosa (all <15 eosinophils/HPF) and none in the proximal esophageal mucosa. There was no eosinophilic infiltration in the distal esophageal sphincter and the middle esophageal muscle. No complication was noted due to muscle biopsy.Conclusions and InferencesSubmucosal tunneling during POEM provides a safe access for direct esophageal muscle biopsy. This is the first report of the simultaneous biopsy of the esophageal mucosa and muscle in patients with achalasia. Contrary to all previously published studies, the association of esophageal eosinophilic infiltration and achalasia was not observed in this small sample study. Based on our findings, immune or autoimmune reaction rather than direct eosinophilic infiltration in the muscle is more likely the cause of achalasia.

Voltage-Gated Sodium Channels Mediating Conduction in Vagal Motor Fibers Innervating the Esophageal Striated Muscle

The vagal motor fibers innervating the esophageal striated muscle are essential for esophageal motility including swallowing and vomiting. However, it is unknown which subtypes of voltage-gated sodium channels (NaV1s) regulate action potential conduction in these efferent nerve fibers. The information on the NaV1s subtypes is necessary for understanding their potential side effects on upper gut, as novel inhibitors of NaV1s are developed for treatment of pain. We used isolated superfused (35 °C) vagally-innervated mouse esophagus striated muscle preparation (mucosa removed) to measure isometric contractions of circular striated muscle evoked by electrical stimulation of the vagus nerve. NaV1 inhibitors were applied to the de-sheathed segment of the vagus nerve. Tetrodotoxin (TTX) applied to the vagus nerve completely abolished electrically evoked contractions. The selective NaV1.7 inhibitor PF-05089771 alone partially inhibited contractions and caused a >3-fold rightward shift in the TTX concentration-inhibition curve. The NaV1.1, NaV1.2 and NaV1.3 group inhibitor ICA-121431 failed to inhibit contractions, or to alter TTX concentration-inhibition curves in the absence or in the presence of PF-05089771. RT-PCR indicated lack of NaV1.4 expression in nucleus ambiguus and dorsal motor nucleus of the vagus nerve, which contain motor and preganglionic neurons projecting to the esophagus. We conclude that the action potential conduction in the vagal motor fibers to the esophageal striated muscle in the mouse is mediated by TTX-sensitive voltage gated sodium channels including NaV1.7 and most probably NaV1.6. The role of NaV1.6 is supported by ruling out other TTX-sensitive NaV1s (NaV1.1-1.4) in the NaV1.7-independent conduction.

Sarcocystis camelicanis increases interleukin (IL)-6 expression in one-humped camels (Camelus dromedarius) from Riyadh and Al Qassim, Saudi Arabia.

Sarcocystis spp. are intracellular protozoan parasites with an intermediate-definitive host life cycle based on a prey–predator relationship. Sarcocystis infection is common among different vertebrates including humans. The pathogenicity of Sarcocystis spp. is of varied significance including a possible lethal effect for the host. The goal of the present study was to investigate the inflammatory activity of Sarcocystis spp. in different organs of naturally infected camels. The tongue, esophagus, heart, diaphragm, and skeletal muscles were collected from 50 camels, and the tissues assessed for the presence of Sarcocystis spp. by macroscopic examination, light microscopy, and transmission electron microscopy (TEM). Moreover, expression of the interleukin (IL)-6 was analyzed using reverse transcriptase quantitative polymerase chain reaction (qPCR). Microscopic Sarcocystis spp. cysts were found in camels. TEM identified the cysts as Sarcocystis camelicanis (S. camelicanis). Sarcocystis infection increased inflammation by stimulation of IL-6 expression in different organs of the camels, particularly in those from the Al-Qassim region.

Effects of Pyridostigmine on Esophageal and Pharyngeal Motility in Dysphagic Patients Undergoing High-Resolution Manometry.

Weak or absent peristalsis of the esophageal musculature is a common finding in ambulatory patients suffering from dysphagia and frequently associated with gastroesophageal reflux. There is currently no pharmacologic intervention that reliably improves esophageal contractility in patients suffering from various esophageal motility disorders. Our objective was to evaluate the acute effects of pyridostigmine on high-resolution manometry parameters in patients suffering from dysphagia with evidence of esophageal dysmotility. Pyridostigmine is an acetylcholinesterase inhibitor which increases effective concentrations of acetylcholine at the neuromuscular junction of both striated and smooth muscle cells. We conducted a prospective crossover study of five patients with dysphagia and proven esophageal dysmotility. Three patients had baseline ineffective esophageal motility and two had achalasia. Patients underwent pharyngeal and esophageal manometry before and after pyridostigmine administration. The median distal contractile integral (DCI), a marker of esophageal contractile vigor, was significantly higher post pyridostigmine administration 3001 (1950.3-3703.2) mmHg × s × cm compared to pre-pyridostigmine DCI of 1229.9 (956.2-2100) mmHg × s × cm; P < 0.001. Pre-pyridostigmine 18/25 (72%) of the patient's swallows was peristaltic compared to 25/25 (100%) post-pyridostigmine; P < 0.005. No other pharyngeal or esophageal high-resolution manometry parameter differed significantly after pyridostigmine administration. The results of this pilot study demonstrate that pyridostigmine acutely improves esophageal contractile vigor in patients suffering from dysphagia with esophageal dysmotility. Further investigation with larger sample size, longer follow-up, side effect profile, and patient-reported outcome measures is still needed to determine the clinical usefulness of pyridostigmine in specific disorders of esophageal motility.

The Effect of Botulinum Toxin Type A Injections on Stricture Formation, Leakage Rates, Esophageal Elongation, and Anastomotic Healing Following Primary Anastomosis in a Long- and Short-Gap Esophageal Atresia Model - A Protocol for a Randomized, Controlled, Blinded Trial in Pigs.

Background:Esophageal atresia (EA) is a congenital malformation affecting 1:3000-4500 newborns. Approximately 15% have a long-gap EA (LGEA), in which case a primary anastomosis is often impossible to achieve. To create continuity of the esophagus patients instead have to undergo lengthening procedures or organ interpositions; methods associated with high morbidity and poor functional outcomes. Esophageal injections of Botulinum Toxin Type A (BTX-A) could enable primary anastomosis and mitigate stricture formation through decreased tissue tension.Methods and Analysis:In this randomized controlled blinded animal trial, 24 pigs are divided into a long- or short-gap EA group (LGEA and SGEA, respectively) and randomized to receive BTX-A or isotonic saline injections. In the LGEA group, injections are given endoscopically in the esophageal musculature. After seven days, a 3 cm esophageal resection and primary anastomosis is performed. In the SGEA group, a 1 cm esophageal resection and primary anastomosis is performed, followed by intraoperative injections of BTX-A or isotonic saline. After 14 days, stricture formation, presence of leakage, and esophageal compliance is assessed using endoscopic and manometric techniques, and in vivo and ex vivo contrast radiography. Tissue elongation is evaluated in a stretch-tension test, and the esophagus is assessed histologically to evaluate anastomotic healing.Ethics and Dissemination:The study complies with the ARRIVE guidelines for animal studies and has been approved by the Danish Animal Experimentation Council. Results will be published in peer-reviewed journals and presented at national and international conferences.Highlights:The optimal management of long-gap esophageal atresia remains controversialPrimary anastomosis could improve functional outcomes and reduce complicationsBotulinum Toxin Type A decreases tissue tension and could facilitate anastomosisReduced tension could further abate the risk for anastomotic stricture and leakageWe present a model to evaluate the method in long- and short-gap esophageal atresia