Pyloric Research Articles

Hydrodynamically Balanced Gastro-Retentive Site Specific Drug Delivery System: An Innovative Approach

Conventional oral dosage forms suffer with many disadvantages. To avoid such limitations controlled release dosage forms are preferred. When these controlled release dosage forms administered by oral route retained in the stomach and release the drug in a controlled fashion continuously in gastrointestinal tract [1]. Controlled release systems also suffer with some limitations such as short gastric retention time and unpredictable short gastric emptying time, which leads to incomplete drug release in the absorption zone results into reduced efficiency of the dose administered [2]. To achieve a desirable prolonged gastric residence time, it is essential to design a site-specific controlled oral dosage form. The prolonged gastric retention of a dosage form increases the total duration of drug release, improves bioavailability, minimizes the drug loss and enhances solubility of poorly soluble drugs in gastric environment [3]. Furthermore, prolonged gastric retention time in the stomach also leads to effective local action in the upper part of the small intestine especially in the treatment of peptic ulcer. Hydrodynamically balanced gastric retentive drug delivery is an innovative approach play important role in prolonging gastric residence time by targeting site specific drug release in the upper intestine for local as well as systemic effect. Over the last few decades different kinds of gastroretentive drug delivery systems being developed. Main among these are: high density (sinking) systems that are designed to sink into the gastric fluid and settle at the bottom of stomach [4], low density (floating) systems that are designed to float on the gastric fluid causing buoyancy [5-7], mucoadhesive systems that are designed to adhere to stomach mucosa [8], unfoldable, extendable, or swellable systems that are designed to limit the emptying of the dosage forms through the pyloric sphincter of stomach [9], superporous hydrogel systems [10] and magnetic systems [11]. The current editorial focused mainly on concise information about hydrodynamically balanced site specific gastroretentive approach for orally administered controlled release dosage forms.

Effects of l-tryptophan on gastric emptying evaluated by breath test in relation to gastric accommodation evaluated by Barostat in rats

Gastric emptying has been known to correlate the pyloric sphincter contractile function and distention-induced gastric relaxation (gastric accommodation). In the present study, the effects of l-tryptophan on the gastric emptying and accommodation were evaluated by breath test using [1-13C]acetic acid and Barostat study, respectively, in rats. l-Tryptophan significantly decreased Cmax and AUC120min and delayed Tmax, indicating the inhibition of gastric emptying. l-Tryptophan significantly enhanced the gastric accommodation. These findings show that l-tryptophan may inhibit the gastric emptying through the enhanced gastric accommodation. Therefore, l-tryptophan may be useful for the therapy of postprandial dyspepsia, especially for early satiety.

Infantile hypertrophic pyloric stenosis (IHPS): a study of its pathophysiology utilizing the newborn hph-1 mouse model of the disease.

Infantile hypertrophic pyloric stenosis (IHPS) is a common disease of unknown etiology. The tetrahydrobiopterin (BH4)-deficient hyperphenylalaninemia-1 (hph-1) newborn mouse has a similar phenotype to the human condition. For hph-1 and wild-type control animals, pyloric tissue agonist-induced contractile properties, reactive oxygen species (ROS) generation, cGMP, neuronal nitric oxide synthase (nNOS) content, and Rho-associated protein kinase 2 (ROCK-2) expression and activity were evaluated. Primary pyloric smooth muscle cells from wild-type newborn animals were utilized to evaluate the effect of BH4 deficiency. One-week-old hph-1 mice exhibited a fourfold increase (P < 0.01) in the pyloric sphincter muscle contraction magnitude but similar relaxation values when compared with wild-type animals. The pyloric tissue nNOS expression and cGMP content were decreased, whereas the rate of nNOS uncoupling increased (P < 0.01) in 1-wk-old hph-1 mice when compared with wild-type animals. These changes were associated with increased pyloric tissue ROS generation and elevated ROCK-2 expression/activity (P < 0.05). At 1-3 days of age and during adulthood, the gastric emptying rate of the hph-1 mice was not altered, and there were no genotype differences in pyloric tissue ROS generation, nNOS expression, or ROCK-2 activity. BH4 inhibition in pyloric smooth muscle cells resulted in increased ROS generation (P < 0.01) and ROCK-2 activity (P < 0.05). Oxidative stress upregulated ROCK-2 activity in pyloric tissue, but no changes were observed in newborn fundal tissue in vitro. We conclude that ROS-induced upregulation of ROCK-2 expression accounts for the increased pyloric sphincter tone and nNOS downregulation in the newborn hph-1 mice. The role of ROCK-2 activation in the pathogenesis of IHPS warrants further study.

Evaluation of the anti-ulcer property of aqueous extract of unripe Musa paradisiaca Linn. peel in Wistar rats

This study investigated the antiulcer activity of aqueous extract of unripe Musa paradisiacal (plantain) peels in rats using ethanol, aspirin, indomethacin and pyloric ligation-induced ulcer models. Fresh peels of M. paradisiaca were extracted in hot water and the yield lyophilised. Distilled water, standard drugs and extract were injected intraperitoneally before inducing ulcer. Lethality test and quantitative phytochemical analyses were also carried out using standard techniques. Results showed that the extract at 50, 100 and 200 mg/kg wt offered 73.87, 80.18 and 81.98% protection, respectively against ethanol-induced ulcer, whereas cimetidine (50 mg/kg) produced 72.07% ulcer protection. There was no significant difference (p > 0.05) between the various groups. The extract also inhibited aspirin-induced ulcer whereas omeprazole (20 mg/kg) significantly enhanced aspirin-induced ulcer. Similar to cimetidine, the extract did not inhibit indomethacin-induced ulceration. Extract (50, 100, and 200 mg/kg) and cimetidine (50 mg/kg) inhibited pyloric ligation-induced ulcer by 100 and 75%, respectively. Findings suggest antiulcerogenic potentials of the extract, thereby supporting its ethnomedicinal use as antiulcer agent. Up to 5000 mg/kg of extract did not cause mortality of the animals, indicating safety of the extract. The extract was rich in flavonoids (1.40 ± 0.02 mg/100 g). Key words: Musa paradisiaca, peptic ulcer, antiulcerogenesis, aspirin-induced ulcer, medicinal plants, flavonoids.

Gene Targeting Study Reveals Unexpected Expression of Brain-expressed X-linked 2 in Endocrine and Tissue Stem/Progenitor Cells in Mice

Identification of genes specifically expressed in stem/progenitor cells is an important issue in developmental and stem cell biology. Genome-wide gene expression analyses in liver cells performed in this study have revealed a strong expression of X-linked genes that include members of the brain-expressed X-linked (Bex) gene family in stem/progenitor cells. Bex family genes are expressed abundantly in the neural cells and have been suggested to play important roles in the development of nervous tissues. However, the physiological role of its individual members and the precise expression pattern outside the nervous system remain largely unknown. Here, we focused on Bex2 and examined its role and expression pattern by generating knock-in mice; the enhanced green fluorescence protein (EGFP) was inserted into the Bex2 locus. Bex2-deficient mice were viable and fertile under laboratory growth conditions showing no obvious phenotypic abnormalities. Through an immunohistochemical analysis and flow cytometry-based approach, we observed unique EGFP reporter expression patterns in endocrine and stem/progenitor cells of the liver, pyloric stomach, and hematopoietic system. Although Bex2 seems to play redundant roles in vivo, these results suggest the significance and potential applications of Bex2 in studies of endocrine and stem/progenitor cells.

The Frequency of Histological Abnormalities in the Muscularis Propria of the Antrum and Pylorus in Gastroparesis Patients

Introduction: Gastroparesis (GP) patients represent a heterogenous population with diabetes mellitus (DM-GP), idiopathic (ID-GP) and post-vagotomy etiologies. Structural studies of their gastric smooth muscle have shown reduced numbers of interstitial cells of Cajal (ICC) and enteric neurons in DM-GP, as well as immune responses and infiltrates in the myenteric plexus in ID-GP. Our goal was to investigate smooth muscle abnormalities in full thickness surgical biopsies of the antrum as well as the pylorus in GP patients. Methods: 16 patients (88% female, 10 DM-GP and 6 ID-GP), aged 20-63, underwent full-thickness antral biopsies during surgery, 15 to place the gastric electrical stimulator (Enterra) and perform a pyloroplasty, and 1 for jejunostomy tube placement. Full-thickness pyloric biopsies were also obtained in 5 of these patients. In addition, antral biopsies were obtained at surgery from 5 female non-GP chronically vomiting patients, aged 19-61 years. The biopsy samples were stained with H&E, trichrome for fibrosis, S100 for myenteric plexus, and C- Kit (CD117) for ICC, where less than 10 per high power field (HPF) was regarded as reduced and also examined for cellular or inflammatory infiltrates or fibrosis in the myenteric plexus. Results: One of 5 controls did have reduced ICC but otherwise all had normal histologic analysis while 6 of the 16 (38%) GP patients had depleted ICC in the antrum (3 DM-GP and 3 ID-GP). Of the 5 pyloric biopsies analyzed, 2 DM-GP patients had reduced ICC. Polymorphonuclear leukocytes (PMN) were noted in nerve bundles in 2 ID-GP patients and aggregates of CD3+ T-cells in nerves were found in 1 DM-GP and 1 ID-GP. Inclusion bodies in the smooth muscle were observed in 3 patients with DM-GP. One patient with DM-GP had decreased ICC in the antrum and pylorus, inclusion bodies, and aggregates of T-cells in nerves. Conclusion: Abnormalities are found in the gastric muscularis propria in the majority (69%) of GP patients. Specifically: 1.) reduced ICC in 38%, 2.) PMN and CD3+ cellular infiltrates in the myenteric plexus of ID-GP patients indicative of a post-infection neural injury in some patients termed “idiopathic,” 3.) inclusion bodies consistent with a smooth muscle myopathy only seen in diabetics, and 4.) decreased pyloric sphincter ICC not previously reported in GP patients.

The orexin system in the enteric nervous system of the bottlenose dolphin (Tursiops truncatus).

This study provides a general approach to the presence and possible role of orexins and their receptors in the gut (three gastric chambers and intestine) of confined environment bottlenose dolphin. The expression of prepro-orexin, orexin A and B and orexin 1 and 2 receptors were investigated by single immunostaining and western blot analysis. The co-localization of vasoactive intestinal peptide and orexin 1 receptor in the enteric nervous system was examined by double immunostaining. Also, orexin A concentration were measured in plasma samples to assess the possible diurnal variation of the plasma level of peptide in this species. Our results showed that the orexin system is widely distributed in bottlenose dolphin enteric nervous system of the all gastrointestinal tract examined. They are very peculiar and partially differs from that of terrestrial mammals. Orexin peptides and prepro-orexin were expressed in the main stomach, pyloric stomach and proximal intestine; while orexin receptors were expressed in the all examined tracts, with the exception of main stomach where found no evidence of orexin 2 receptor. Co-localization of vasoactive intestinal peptide and orexin 1 receptor were more evident in the pyloric stomach and proximal intestine. These data could suggest a possible role of orexin system on the contractility of bottlenose dolphin gastrointestinal districts. Finally, in agreement with several reports, bottlenose dolphin orexin A plasma level was higher in the morning during fasting. Our results emphasize some common features between bottlenose dolphin and terrestrial mammals. Certainly, further functional investigations may help to better explain the role of the orexin system in the energy balance of bottlenose dolphin and the complex interaction between feeding and digestive physiology.

Optimum concentration and dose of ropivacaine for caudal block in neonates undergoing laparotomy under general anesthesia: evaluation of postoperative outcome

Objective To investigate the optimum concentration and dose of ropivacaine for caudal block in the neonates undergoing laparotomy under general anesthesia.Methods One hundred pediatric patients of both sexes,aged 9-30 days,weighing 2.5-4.5 kg,scheduled for elective pyloromyotomy,were randomly divided into 5 groups (n =20 each) using a random number table:control group (group C),0.10％ ropivacaine 1.0 ml/kg group (group 0.1％ L1),0.15 ％ ropivacaine 1.0 ml/kg group (group 0.15 ％ L1),0.10 ％ ropivacaine 1.2 ml/kg group (group 0.10 ％ L2),and 0.15 ％ ropivacaine 1.2 ml/kg group (group 0.15 ％ L2).Anesthesia was induced with sevoflurane and cisatracurium.The pediatric patients were tracheally intubated and mechanically ventilated.Remifentanil was infused intravenously at 0.2-0.3 μg· kg-1 · min-1 in group C.In 0.10 ％ L1,0.15 ％ L1,0.10 ％ L2 and 0.15％L2 groups,the corresponding concentrations and doses of ropivacaine were injected into the sacral canal under the guidance of ultrasound.The operation was started at 15 min after administration and sevoflurane was inhaled and the end-tidal concentration of sevoflurane was maintained at 0.8-1.0 MAC.Before induction (T1),at pyloric muscle retraction (T2),and at 4,8,12 and 24 h after operation (T3-6),blood samples were collected from the central vein for determination of plasma concentrations of cortisol and interleukin-6 (IL-6).Pain was assessed using CRIES score at T3-6.When CRIES scores ＞ 3,10％ chloral hydrate 0.5 ml/kg was given by retention enema for analgesia,and the requirement for chloral hydrate was recorded.The emergence time,extubation time,duration of stay in post-anesthesia care unit (PACU) and hospital discharge time were recorded.Bradycardia and hypotension during operation,and development of motor block of lower extremities,infection and dehiscence of incision,vomiting,and urinary retention after operation were also recorded.Results Compared with group C,no significant changes were found in the emergence time,extubation time,duration of stay in PACU,hospital discharge time,plasma concentrations of cortisol and IL-6,the requirement for chloral hydrate,and the incidence of bradycardia,hypotension,motor block of lower extremities,and infection and dehiscence of incision in 0.10％ L1 and 0.15 ％ L1 groups,the emergence time,extubation time,duration of stay in PACU,hospital discharge time were significantly shortened,and the plasma concentrations of cortisol and IL-6,requirement for chloral hydrate,and the incidence of hypotension and infection of incision were decreased in 0.10％ L2 and 0.15％ L2 groups,and the incidence of vomiting and urinary retention was increased in 0.15％ L1 and 0.15％ L2 groups.Compared with group 0.10％ L2,the incidence of vomiting and urinary retention was significantly decreased,and no significant changes were found in the other parameters mentioned above in 0.15％ L2 group.Conclusion The optimum concentration and dose of ropivacaine are 0.10％ and 1.2 ml/kg,respectively,for caudal block in the neonates undergoing laparotomy under general anesthesia. Key words: Amides ; Anesthesia, caudal ; Anesthesia, general; Infant, newborn

Submucosal Dissection of Pyloric Neoplasms Is Feasible

Neoplasms occurring in the pylorus are more difficult to remove by endoscopic submucosal dissection (ESD) than lesions that occur in most other areas

Early human experience with per-oral endoscopic pyloromyotomy (POP).

Gastroparesis is a condition characterized by delayed gastric emptying, and a constellation of symptoms, including nausea, vomiting, early satiety, and bloating. Although current surgical options such as pyloroplasty have been shown to be effective, an endoscopic submucosal myotomy technique may be applied to divide the pyloric sphincter without surgical access. Such endoscopic technique may provide the benefits of a natural orifice procedure, and improve gastric emptying in gastroparetic patients. Per-oral pyloromyotomy (POP) was performed in seven female patients aged 33-65 years (mean 51 years). All patients had a pre-operative work-up that included upper endoscopy, and a gastric emptying study. A pH study, and esophageal manometry were also performed when a concomitant fundoplication was considered. POP was technically successful in all seven cases. There were no immediate procedural complications. Perioperative, complications included: one patient with an upper GI bleed 2 weeks post-procedure, necessitating transfusions, and endoscopic clipping of a pyloric channel ulcer; one patient who experienced difficulty swallowing post operatively, delaying discharge by 1 day; and one patient who developed a hospital-acquired pneumonia, delaying discharge by several days. Six of the seven patients experienced significant symptomatic improvement following the procedure. Three month follow-up nuclear medicine solid-phase gastric emptying studies are currently available for 5 of the 7 patients. Normal gastric emptying at 4 h was noted in four of five patients (80 %). One patient did not respond to endoscopic management subsequently underwent an uneventful laparoscopic pyloroplasty, which also failed to significantly improve her symptoms. POP is a technically safe and feasible endoscopic procedure. Early follow-up suggests promising symptomatic improvement as well as objective improvement in gastric emptying. Additional clinical experience is required to establish the role of this technique in the management of gastroparesis.

Roles for Nkx2-5 and Gata3 in the ontogeny of the murine smooth muscle gastric ligaments.

The gastric ligaments are superficial cord-like structures, located on the lesser curvature of the stomach, that extend from the pylorus to the esophagus. These ligaments have been documented in a wide variety of mammalian species, including humans, but their composition and ontogeny is unexplored. Here, we demonstrate that, during ontogeny, the gastric ligaments are first visible as extensions from a C-shaped domain of Gata3-expressing cells that surround the future pylorus; this domain will later give rise to the pyloric outer longitudinal muscle (OLM). The open ends of the C are located ventrally, and, beginning at embryonic day (E) 13.5, the ligaments grow anteriorly from these points. Whereas most other ligaments of the stomach are neurovascular in nature, the gastric ligaments are composed of smooth muscle cells that mature between E14.5 and E16.5. The gastric ligaments coexpress the transcription factors Gata3, Nkx2-5, and Sox9, and germline loss of Gata3 or conditional deletion of Nkx2-5 abrogates Sox9 expression and impairs gastric ligament smooth muscle development; similar phenotypes were previously seen in the OLM. In accord with this molecular contiguity between the OLM and gastric ligaments, three-dimensional image reconstruction highlights physical contiguity between these smooth muscle structures, suggesting that they may work together as a unit to control flexure of the pyloric region, a function similar to the ligament of Treitz at the duodenojejunal junction. These findings may have implications for our understanding of normal pyloric sphincter function, as well as the common human congenital pathology idiopathic hypertrophic pyloric stenosis.

Imaging presentation of pylorus obstruction caused by foreign bodies in the gastric anrum and granulomatous inflammation

Pylorus obstruction caused by foreign bodies in the gastric anrum and granulomatous inflammation is rarely seen.The clinical symptoms of this disease are unspecific.Combination of X-ray radiography,computed tomography and gastroscopy could make definite diagnosis.Differential diagnosis between pylorus obstruction and peptic ulcer,gastric cancer and duodenal obstruction should be done before operation.On April 13,2012,a patient with pylorus obstruction caused by foreign bodies in the gastric anrum and granulomatous inflammation was treated at the Second Hospital of Jiaxing,the imaging characteristics of the disease were summarized to provide referrence for the diagnosis and treatment of this disease. Key words: Pylorus obstruction; Foreign body ; Granulomatous inflammation

Mo1296 EndoFLIP As a Novel Method to Evaluate the Pyloric Sphincter in Patients With Gastroparesis

Gastroparesis is a complication of diabetes mellitus. Gastroparetic symptoms of nausea, vomiting, and early satiety and the delayed gastric emptying can make glucose control difficult. The impact of gastroparesis on diabetes management and control from the patient perspective has not been systematically studied. The aim of this study was to identify patient perceptions regarding the impact of gastroparesis on managing their diabetes. Methods: Diabetic patients being referred for gastroparesis and having delayed gastric emptying on gastric scintigraphy were enrolled in this prospective study. Clinical and demographic characteristics were obtained by interview, medical record and laboratory reports. Gastroparetic symptom severity was assessed with the Patient Assessment of Upper GI Symptoms (PAGI-SYM) on a none (0) to very severe (5) scale. A questionnaire developed for this study examined the impact on gastroparesis on diabetes related symptoms and control, with responses ranging from strongly disagree (-2) to strongly agree (+2). Results: 33 individuals with diabetic gastroparesis (25 T1DM and 8 T2DM; average age 44±3 (SEM) years; 26 females) participated. All but 3 patients were taking insulin. Mean HgbA1c was 8.1±0.2% with range from 6.6 to 11.2%. Gastric retention at 4 hrs averaged 37±4% (normal<10%). Duration of diabetes averaged 18.5±2.0 years and gastroparetic symptoms 5.6±1.7 years. Patients rated their most severe symptoms of gastroparesis as nausea (3.7±0.2), early satiety (3.7±0.2), and postprandial fullness (3.8±0.2). Patients with T1DM had greater gastric retention (41±4 vs 23±4% retention at 4 hrs; p<0.05), greater HgbA1c (8.4±1.7 vs 6.3±0.9; p=0.06), and greater vomiting severity (2.7±0.4 vs 0.9±0.6; p=0.03) than patients with T2DM. The majority of diabetic subjects identified that since their diagnosis of gastroparesis, their diabetes was more difficult to control (23 of 33 patients) and that extra time and effort for care of their diabetes was required (22 of 33). In contrast to T2DM, patients with T1DM expressed that since developing gastroparesis, their blood sugars have been higher (0.7±0.3 vs 0.0±0.5; p=0.20), have had more frequent episodes of hypoglycemia (0.6±0.2 vs -0.6±0.4; p<0.01), and found their gastroparetic symptoms worsened with if blood sugars were too high (0.8±0.2 vs 0.1±0.5; p=0.10). Few diabetic patients of either group (7 of 33) felt that their gastroparesis symptoms improved if blood sugars were controlled. Conclusions: Gastroparesis has a significant impact on patients' perceived ability to self-manage and control their diabetes. T1DMpatients, in particular, associate their gastroparesis with episodes of hyperand hypo-glycemia, and find their gastroparetic symptoms worsen with poor control. Future research should focus on strategies to support patient self-management for diabetics with gastroparesis.

Morphology of the Pylorus of Bombyx mori (Linnaeus) (Lepidoptera: Bombycidae).

The pylorus is a segment of the hindgut of great morphological diversity, which is subdivided into the posterior interstitial ring, pyloric cone, and pyloric valve. There is no morphological information on Bombyx mori (L.) hybrids, which is an insect of economic interest to Brazil. Consequently, this study aimed to analyze the morphology of the pylorus of hybrid larvae of fifth instars of B. mori from crossbreeding of Chinese and Japanese races. These were anesthetized, and the pylorus was fixed and processed by light microscopy and scanning electron microscopy. The pylorus presented as a separate compartment, consisting of a simple epithelium, with large variation in cell morphology, covered on the luminal side by an intima with specializations in some areas, the spicules. The musculature was formed by bundles of striated muscle fibers in longitudinal and circular arrangement. These fibers were multinucleated with central and peripheral nuclei, operating in peristalsis. The morphology of the pylorus is a reflection of functional dynamism, and this study provided a better understanding of its physiology, which promotes the regulated movement of the bolus, preventing reflux and directing it towards the ileum in the formation of fecal pellets.

Successful Treatment of Life-Threatening Metabolic Alkalosis Due to Pyloric Stenosis: A Rare Case

Alkalemia is defined as blood pH > 7.40 and if severe alkalemia pH > 7.60. Metabolic alkalosis is one of the common in-hospital acid-base disorders. Gastric outlet obstruction secondary to pyloric stenosis has been reported most frequent causes of severe metabolic alkalosis resulting from volume and hydrogen ion loss. Mortality is directly related to the severity of the acid base disturbances. As serum pH exceeds 7.60, the mortality also increases and can reach up to 80%. The current case is of a 41-year-old male with history of peptic ulcer disease presented with muscle cramps and confusion, and found to have severe metabolic alkalosis with an arterial pH of 7.91 mm Hg . He had superimposed acute kidney injury and severe hypokalemia which was successfully treated with aggressive volume repletion, hydrochloric acid infusion and surgery for pyloric stenosis. This is the severe reported life compatible level of metabolic alkalosis (pH: 7.91) to best our knowledge. J Med Cases. 2014;5(5):312-314 doi: http://dx.doi.org/ 10.14740 / jmc1623w

A comparative study on endoscopic placement methods of nasal jejunum nutrition tube

Objective To compare the clinical application effect of placing nasal jejunum nutrition tube by gastroscope and transnasal gastroscope. Methods In Jun 2011, the patients who need nasal jeju- num nutrition tube due to obstruction of gastric antrum, pylorus and duodenum were assigned randomly into gastroscope pushing group （GP） and transnasal gastroscope guide wire group （TNGGW）. Operation time, achievement ratio, and tube displacement ratio were compared. Results Nasal jejunum nutrition tubes were successfully placed in all patients by two methods. In GP group, the success rate was 85%, and mean time cost was （750. 3 ± 445.9） s, and tube displacement ratio was 30%. In TNGGW group, the success rate wasl00%, and mean time cost was （ 157.4 ± 79. 3）s with no tube displacement ratio. There was a statisti- cally significant difference in mean time cost between GP group and TNGGW group （ P 〈 0. 01 ）. Conclusion It is a more reliable and convenient method to place nasal jejunum nutrition tube by transnasal gastroscope than by gastroseope. Key words: Jejunum; Enteral nutrition; Transnasal gastroscope; Guide wire

Investigation of Helicobacter pylori infection among children who underwent gastroscopy from 2001 to 2010 in Nanjing Area

Objective To investigate Helicobacter pyloric (Hp) infection in children who underwent gastroscopy in Nanjing area. Methods From Jan.2001 to Dec.2010, 2 990 pediatric patients with gastrointestinal symptoms who underwent endoscopy and Hp rapid urease test of gastric mucosa specimens. Results There were 2 990 patients who underwent gastroscopy during the 10 years including 1 718 cases of male and 1 272 cases of female.The rate of Hp infection was 53.8%(924/1 718 cases) and 52.4%(667/1 272 cases) in male and female, respectively.There was no significant difference (χ2=0.532, P>0.05). From Jan.2001 to Dec.2005, 611 patients were tested and the rate of Hp infection was 66.9%(409/611 cases). From Jan.2006 to Dec.2010, 2 379 patients were tested and the rate of Hp infection was 49.7%.There was significant difference(χ2=58.13, P=0.01) between the 2 groups.The rate of Hp infection were 49.6%, 48.1%, 55.2%, 60.0% in 0-6 years group, >6-9 years group, >9-12 years group, and>12 years group, respectively.There was significant difference among the 4 different age groups(χ2=23.66, P<0.01). The rate of Hp infection in nodular gastritis(61.4%) was higher than that in chronic superficial gastritis (50.6%). There was significant difference between the 2 groups(χ2=7.42, P<0.01). The rate of Hp infection in allergic purpura (46.2%)was higher compared with the children with normal gastroscopy results(15.9%). There was significant dif-ference between the 2 groups(χ2=10.19, P<0.01). Conclusions There is gradually downward trend by year in the rate of Hp infection of children who underwent gastroscopy in Nanjing area by year.The rate of Hp infection is increa-sing with the age after the age of 6 years.Hp infection may play a role in the nodular gastritis and allergic purpura. Key words: Gastroscopy; Helicobacter pylori; Child

Substance P is essential for maintaining gut muscle contractility: a novel role for coneurotransmission revealed by botulinum toxin

Substance P (SP) is commonly coexpressed with ACh in enteric motor neurons, and, according to the classical paradigm, both these neurotransmitters excite smooth muscle via parallel pathways. We hypothesized that, in addition, SP was responsible for maintaining the muscular responsiveness to ACh. We tested this hypothesis by using botulinum toxin (BoNT/A), a known blocker of vesicular release of neurotransmitters including ACh and neuropeptides. BoNT/A was injected into rat pyloric sphincter in different doses; as control we used boiled BoNT/A. At the desired time point, pylorus was dissected out and pyloric contractility was measured ex vivo in an organ bath and by measuring phosphorylation of myosin light chain 20 (MLC20). BoNT/A (10 IU) significantly reduced the response of pyloric muscle to exogenous ACh, an effect that was accompanied by reduced MLC20 phosphorylation in the muscle. Both effects were reversed by exogenous SP. CP-96345, a NK1 receptor antagonist, blocked the ability of exogenous SP to reverse the cholinergic hyporesponsiveness as well as the reduction in MLC20 phosphorylation induced by BoNT/A. In conclusion, we have identified a novel role for SP as a coneurotransmitter that appears to be important for the maintenance of muscular responsiveness to the principal excitatory neurotransmitter, ACh. These results also provide new insight into the effects of botulinum toxin on the enteric nervous system and gastrointestinal smooth muscle.

Human intestinal tract length and relationship with body height (916.4)

Despite its great importance in surgical approaches to intestinal resection, little definitive information is available on human gut tract length. Previous studies have correlated various measures with sex, age, weight, height, and “ethnic background.” Better knowledge of these relationships may aid in avoidance of surgical complications such as the nutritional disorder “short bowel syndrome.” This study examined length of the intestinal tract and its components (small intestine and colon) in 10 donor bodies. The small intestine was measured from pyloric sphincter to ileocecal junction while the large intestine was measured from caecum to sigmoid colon. Results indicate strong correlation (r=0.827) between colon length and body height from cranial vertex to heel, likely a result of the colon's function in water absorption. This relationship was stronger than the ones among total gut length, small intestine length, and body height. In particular, the weakest correlation was between small intestine length and height (r=0.337), suggesting that the combined lengths of the duodenum, jejunum, and ileum are not closely related to body size. Indeed, this measure had the highest coefficient of variation (0.26) while colon length showed the lowest (0.085). Future research will test hypotheses related to population differences in gut length and its physiologic consequences.

Laryngeal Granuloma in Experimental Rats With Gastroesophageal Reflux Disease and Mechanically Injured Vocal Cord Mucosa

This study was undertaken to elucidate the mechanisms underlying laryngeal granuloma formation in a rat model of gastroesophageal reflux disease (GERD) with mechanically injured vocal cord mucosa. The rat model of GERD was surgically created by tying the pyloric sphincter and ligating the transitional region between the forestomach and the glandular portion (limiting ridge). The control rats received only a midline incision. In all the animals, a plastic bar was inserted into the trachea, and moved vertically thrice in 3 seconds to cause mechanical injury of the vocal cord mucosa. The rats were sacrificed 2 weeks postsurgically, and their pharynx and larynx were observed histologically. Granulomas were observed in the vocal cord mucosa of the GERD group (3 of 5 animals); they presented a similar pathological structure to that of human laryngeal granulomas. In contrast, only abrasions and blisters were observed on the vocal cord mucosa in the control group (all 5 animals). The development of laryngeal granuloma may involve both mechanical injury and gastric acid reflux.