Gastric Region Research Articles

Development and characterization of gastro-floating sustained-release granules for enhanced bioavailability of patchouli oil

Patchouli oil (PO), extracted from Pogostemon cablin Benth., a prominent aromatic plant of the Lamiaceae family, has shown considerable protective effects against gastrointestinal infections, particularly those induced by Helicobacter pylori. This study aimed to develop a gastro-floating multi-unit system for PO to enhance its gastric retention and oral bioavailability. MethodsThe oil-laden granules were prepared using colloidal silicon dioxide (CSD) for oil adsorption and to provide buoyancy, along with ethyl cellulose (EC) and hydroxypropyl methyl cellulose (HPMC) to form a sustained-release matrix. The CSD exhibited favorable characteristics for oil adsorption and floating. Compatibility between PO and CSD was affirmed through DSC thermograms and FTIR spectra. The obtained granules demonstrated a sustained release profile, achieving over 90 % release within 10 h without an initial burst. After oral administration, the granules were observed to remain in the gastric region of rats for over 7 h. The bioavailability of patchouli alcohol from the optimized granules was significantly higher than that from of the PO-loaded powders. The gastro-floating sustained-release granules, based on a CSD/EC/HPMC matrix, offer a simple yet effective strategy to improve the delivery efficacy of PO against Helicobacter pylori infections in the gastric region.

Evaluation of the toxic potential of ethyl methanesulphonate (EMS) on Hydra vulgaris

The effect of EMS at final concentration of 0.09, 0.18, 0.27 and 0.37mM was studied on Hydra vulgaris using morphological, regeneration, oxidative stress markers and DNA damage as parameters. The morphological scores showed a significant dose dependent difference in the Hydra exposed to 0.18, 0.27, and 0.37mM of EMS for 24, 48, 72 and 96 hrs. The regeneration scores also showed a significant difference in the gastric region of Hydra exposed to 0.37mM of EMS for 48hr. A significant difference in the scores of regeneration was observed for the mid body portion exposed to 0.18, 0.27 and 0.37mM of EMS for 72 and 96hr of duration compared to control. A dose-dependent significant increase in the activities of glutathione-S-transferase (GST), catalase (CAT), and superoxide dismutase (SOD) was observed compared to control. The thiobarbituric acid reactive species (TBARS) levels were also significantly increased compared to control. The genotoxic damage was assessed in the cells of gastric region of the Hydra exposed to 0.09, 0.18, 0.27 and 0.37mM of EMS for 48hr by performing comet assay. A significant dose-dependent increase in the DNA damage was observed compared to control.

Ferrous ascorbate non-effervescent floating mini-caplets as an oral iron supplement.

This research aimed to develop non-effervescent floating mini-caplets of Ferrous Ascorbate (FA) using low-density polymers to overcome the problems of poor bioavailability associated with immediate-release iron products.Methods:The excipients and method (melt granulation) were selected based on pre-and post-compression parameters in trial batches. The formulation was optimized by a full factorial 32 experimental design. An optimized formulation was evaluated for drug release kinetic, accelerated stability study, and in vivo study in healthy adult New Zealand female rabbits.Results:The optimized formulation F6 mini-caplets (42.5% FA, 45% Glyceryl palmitostearate asPrecirol, 10% polyvinyl pyrrolidone K-30, and 2.5% lactose) were found to have instant floating and 12h floating duration in 0.1N Hydrochloric acid (HCl) dissolution medium. In vitro drug release (diffusion mechanism) at 1h and 5h was 30-35% and 65-70%, respectively. It was found stable for three months under an accelerated stability study. In vivo study showed significantly increased serum iron levels and decreased unsaturated iron binding capacity (UIBC) in the test group (optimized formulation) compared to control and standard (immediate-release iron).Conclusion:Based on the in vitro and in vivo results, we conclude that non-effervescent floating FA mini-caplets have higher bioavailability compared to immediate release FA, which may be attributed to prolonged iron release at its absorption site due to their retention in the gastric region. Hence, non-effervescent floating FA mini-caplets may act as a potential approach for iron deficiency.

Deep Learning-Based Real-Time Organ Localization and Transit Time Estimation in Wireless Capsule Endoscopy.

Wireless capsule endoscopy (WCE) has significantly advanced the diagnosis of gastrointestinal (GI) diseases by allowing for the non-invasive visualization of the entire small intestine. However, machine learning-based methods for organ classification in WCE often rely on color information, leading to decreased performance when obstacles such as food debris are present. This study proposes a novel model that integrates convolutional neural networks (CNNs) and long short-term memory (LSTM) networks to analyze multiple frames and incorporate temporal information, ensuring that it performs well even when visual information is limited. We collected data from 126 patients using PillCam™ SB3 (Medtronic, Minneapolis, MN, USA), which comprised 2,395,932 images. Our deep learning model was trained to identify organs (stomach, small intestine, and colon) using data from 44 training and 10 validation cases. We applied calibration using a Gaussian filter to enhance the accuracy of detecting organ boundaries. Additionally, we estimated the transit time of the capsule in the gastric and small intestine regions using a combination of a convolutional neural network (CNN) and a long short-term memory (LSTM) designed to be aware of the sequence information of continuous videos. Finally, we evaluated the model's performance using WCE videos from 72 patients. Our model demonstrated high performance in organ classification, achieving an accuracy, sensitivity, and specificity of over 95% for each organ (stomach, small intestine, and colon), with an overall accuracy and F1-score of 97.1%. The Matthews Correlation Coefficient (MCC) and Geometric Mean (G-mean) were used to evaluate the model's performance on imbalanced datasets, achieving MCC values of 0.93 for the stomach, 0.91 for the small intestine, and 0.94 for the colon, and G-mean values of 0.96 for the stomach, 0.95 for the small intestine, and 0.97 for the colon. Regarding the estimation of gastric and small intestine transit times, the mean time differences between the model predictions and ground truth were 4.3 ± 9.7 min for the stomach and 24.7 ± 33.8 min for the small intestine. Notably, the model's predictions for gastric transit times were within 15 min of the ground truth for 95.8% of the test dataset (69 out of 72 cases). The proposed model shows overall superior performance compared to a model using only CNN. The combination of CNN and LSTM proves to be both accurate and clinically effective for organ classification and transit time estimation in WCE. Our model's ability to integrate temporal information allows it to maintain high performance even in challenging conditions where color information alone is insufficient. Including MCC and G-mean metrics further validates the robustness of our approach in handling imbalanced datasets. These findings suggest that the proposed method can significantly improve the diagnostic accuracy and efficiency of WCE, making it a valuable tool in clinical practice for diagnosing and managing GI diseases.

The investigation of B12 deficiency leading to the serendipitous diagnosis of gastric carcinoid tumour

Gastric carcinoid is a rare type of gastric malignancy accounting for around 7% of all gastrointestinal neuroendocrine tumours (NETs). While most gastric NETs (gNETs) are readily visible through direct visualisation by upper endoscopy, around 25% of gastric carcinoids are invisible because they are located in the submucosal gastric regions of the body and fundus. gNETs located in the intra-mucosal areas can be identified by gastric mapping; this can be done by taking random gastric biopsies from the antrum, body and fundus. We report a case of a well-differentiated gastric NET type 1 with atrophic gastritis diagnosed on upper endoscopy and pathological immunohistochemistry staining.

Enhanced curcumin solubility in epichlorohydrin engineered β-Cyclodextrin copolymer for gastric maladies

The present work relates to a β-cyclodextrin based drug delivery system with epichlorohydrin as cross-linking agent, with higher binding efficiency of the drug curcumin and enhanced solubility of the curcumin in complex form when simulated in gastric fluid and increased sustained release of curcumin from complex for 2 h to act in gastric region. Although cross-linking with epichlorohydrin (EPC) is a process studied long time ago, however its use as a gastric solubility enhancer for curcumin has been studied for the first time. The synthesized polymer was well characterized by FT-IR, SEM, XRD, TGA and particle size analysis. The polymer enhanced the water solubility of curcumin by ∼ 800–850 times and the gastric solubility was increased by ∼ 1400–1500 times and acted as a sustained release system as verified by the pepsin inhibition studies which makes it a potential drug carrier for gastric specific drug targeting that can be a promising treatment for gastritis and gastric ulcers.

Descriptions of new and rare crabs associated with coral rubble and sponges from Kanyakumari, southeastern Arabian Sea, southern India (Decapoda: Brachyura: Epialtidae and Pilumnidae).

Three new brachyuran crab species are described from coral rubble and sponges collected in the southern Indian state of Tamil Nadu. The epialtid, Acanthophrys keeae n. sp., was obtained from coral rubble and is the first species from the genus reported from the Indian Ocean. It is most similar to A. costatus Griffin & Tranter 1986, from eastern Australia, but can be distinguished by the proportionately longer postorbital spine, more strongly granulated gastric region, relatively less inflated and narrower branchial region, sinuous outer margin of the basal antennal article which has the median part concave, almost smooth merus of the cheliped, more elongate male anterior thoracic sternum, more triangular male pleon, and the distal two-thirds of the male first gonopod being almost straight. The pilumnid, Latopilumnus ajmali n. sp., was found in the sponge, Callyspongia (Cladochalina) diffusa (Ridley, 1884), and is characterised by its carapace and pereiopods being covered by a relatively dense coat of short setae with only scattered simple long setae, and the dorsal carapace surface being almost smooth with the regions poorly demarcated. Vellumnus intonsus n. sp. (Pilumnidae) was present in coral rubble, is morphologically most similar to V. penicillatus (Gordon, 1930) (Hong Kong) and V. pygmaeus Takeda, 1977 (Japan) but can be separated by the lateral lobule of the front being separated from the frontal lobes by a deep cleft, the more prominently convex supraorbital margin, triangular external orbital tooth, presence of larger granules on the cheliped carpus and chela, and the distal part of the male first gonopod is proportionately stouter and distinctly hooked.

Formulation and evaluation of sustained release floating tablets of venlafaxine using natural polymers

Over the past three decades, oral controlled-release dosage forms have been developed due to their therapeutic advantages, such as ease of administration, patient compliance, and flexibility in formulation. However, this approach has faced physiological difficulties, such as the inability to contain and position the controlled drug delivery system within the desired region of the gastrointestinal tract (GIT) due to variable gastric emptying and motility. Venlafaxine is an antidepressant and a serotonin and norepinephrine reuptake inhibitor (SNRI). Its active metabolite, desvenlafaxine, works by blocking the reuptake of serotonin and norepinephrine, which are key neurotransmitters in mood regulation. Gastroretentive dosage forms can stay in the gastric region for several hours and significantly prolong the gastric residence time of drugs. Natural materials have been extensively used in drug delivery because they are readily available, cost-effective, eco-friendly, capable of many chemical modifications, potentially degradable, and compatible due to their natural origin. Keywords: Sustained Release Floating Tablets, Venlafaxine,

Clinicopathological and endoscopic features of Helicobacter pylori infection-negative gastric cancer in Japan: a retrospective study.

Helicobacter pylori infection-negative gastric cancer (HPNGC) has not been systematically investigated in consecutive patients. Hence, this study aimed to investigate the clinicopathological and endoscopic features of HPNGC. This single-center retrospective study selected participants from patients with gastric cancer who were treated at the Fukuoka University Chikushi Hospital between January 2013 and December 2021. Only patients diagnosed with HPNGC were enrolled, and their clinicopathological and endoscopic features were analyzed in detail. The prevalence of HPNGC in the present study was 2.6% (54/2112). The types of HPNGC observed in each gastric region were as follows: advanced gastric cancer was observed in the cardia; gastric adenocarcinoma of fundic-gland differentiation, gastric adenocarcinoma of foveolar-type presenting with whitish elevation and raspberry-like foveolar-type gastric adenocarcinoma, gastric adenocarcinoma arising in polyposis, and gastric adenocarcinoma with autoimmune gastritis were observed in the fundic gland region ranging from the gastric fornix to the gastric body; signet-ring cell carcinoma was observed in the gastric-pyloric transition region ranging from the lower gastric body to the gastric angle; and well-differentiated tubular adenocarcinoma with low-grade atypia was observed in the antrum. This study revealed that tumors from each gastric region exhibited distinct macroscopic and histological types in HPNGC.

Design of floating formulations and antiulcer activity of Desmostachya bipinnata

The study aims to design and optimize the floating formulations of the aqueous extract of Desmostachya bipinnata (ADB) to treat peptic ulcers. The trial concentrations of HPMC E50, HPMC K4M, and Carbopol 940 were used as factors, and floating lag time, total floating time, and % drug release at 12 h were used as responses. The formulation underwent evaluation for different parameters: aspirin-induced ulcers in rats assessed the antiulcer activity, and X-ray studies in rabbits evaluated the gastroretentive nature. The optimized formulation has shown a floating lag time of 32 s and floated in the gastric medium for more than 9 h with a maximum drug release of 93% at the end of 12 h by following the Korsmeyer-Peppas drug release mechanism. The optimized formulation has good flow properties. The FT-IR, DSC, and XRD studies show ADB and excipients didn't show any incompatibility. The formulation has shown significant antiulcer activity against aspirin-induced ulcers in rats, with an ulcer index of 3.38 ± 0.24 and inhibition of 76.67 ± 0.56%. The in vivo X-ray imaging proved the gastric retention of the formulations for more than 8 h. The results of the formulations demonstrate the floating ability and sustained drug release of the tablet responsible for treating peptic ulcers to show a localized effect in the gastric region and to maintain the ROS levels.Graphical

Improved gastric residence time of famotidine by raft-forming drug delivery system using DOE.

This study investigated the raft-forming suspension of famotidine as an anti-reflux formulation to improve the oral bioavailability of narrow absorption window drugs by enhancing gastric residence time (GRT) and preventing gastro-esophageal reflux disease (GERD). Various combinations of raft-forming agents, such as Tragacanth gum (TG), guar gum (GG), and xanthan gum (XG), were evaluated alongside sodium alginate (SA) to develop an effective raft. Preformulation studies and preliminary screening were conducted to identify the most suitable raft-forming agent, and GG was chosen due to its mucilaginous properties. The formulation was optimized using a 32 full factorial design, with the quantities of GG and SA as independent factors and apparent viscosity and in-vitro drug release (%) as dependent factors. The in vivo floating behavior study was performed for optimized and stabilized formulation. Among the tested batches, F6 was selected as the optimized formulation. It exhibited desirable characteristics such as adequate raft weight for extended floating in gastric fluid, improved apparent viscosity, and a significant percentage of drug release at 12h. A mathematical model was applied to the in-vitro data to gain insights into the drug release mechanism of the formulation. The stability of the suspension was assessed under accelerated conditions, and it demonstrated satisfactory stability. The formulation remains floating in the Rabbit stomach for more than 12h. It concludes that the developed formulation has enhanced bioavailability in the combination of GG and SA. The floating layer of the raft prevents acid reflux, and the famotidine is retained for an extended period of time in the gastric region, preventing excess acid secretion. The developed formulations are effective for stomach ulcers and GERD, with the effect of reducing acid secretion by H2 receptor antagonists.

Evidências de Helicobacter spp. em gatos domésticos na região central do Rio Grande do Sul - pré-estudo

ABSTRACT Non-Helicobacter pylori Helicobacters(NHPH) account for causing moderate and severe gastritis in humans. Moreover, they have already been documented in the oral cavity of feline animals. The current study aims to investigate Helicobacter spp. incidence in necropsied domestic cats from central Rio Grande do Sul. Stomach, liver, and bile samples derived from 30 cats’ cadavers were subjected to rapid urease test (RUT), histopathological analysis, PCR, and nucleotide sequencing to investigate the genetic material presence and to identify the main phylogenetic group. Based on RUT results, 64.2% and 53.5% of patients were positive for gastric body and pyloric antrum, respectively. Ten out of these 15 patients were male (70%) and the positive result observed for the pyloric antrum was associated with males. Mild histopathological changes were observed in most gastric and liver samples. Gastric samples subjected to PCR presented positive results in 60.7%, whereas liver samples accounted for positive results in 17.8% and bile samples, in 3.5% of cases. There was high nucleotide identity with NHPH species. This study has found evidence that NHPH can be found in the gastric and hepatic regions, as in the bile of domestic cats, besides emphasizing the zoonotic potential of this disease

Biomechanical characterization of the passive porcine stomach

The complex mechanics of the gastric wall facilitates the main digestive tasks of the stomach. However, the interplay between the mechanical properties of the stomach, its microstructure, and its vital functions is not yet fully understood. Importantly, the pig animal model is widely used in biomedical research for preliminary or ethically prohibited studies of the human digestion system. Therefore, this study aims to thoroughly characterize the mechanical behavior and microstructure of the porcine stomach. For this purpose, multiple quasi-static mechanical tests were carried out with three different loading modes, i.e., planar biaxial extension, radial compression, and simple shear. Stress-relaxation tests complemented the quasi-static experiments to evaluate the deformation and strain-dependent viscoelastic properties. Each experiment was conducted on specimens of the complete stomach wall and two separate layers, mucosa and muscularis, from each of the three gastric regions, i.e., fundus, body, and antrum. The significant preconditioning effects and the considerable regional and layer-specific differences in the tissue response were analyzed. Furthermore, the mechanical experiments were complemented with histology to examine the influence of the microstructural composition on the macrostructural mechanical response and vice versa. Importantly, the shear tests showed lower stresses in the complete wall compared to the single layers which the loose network of submucosal collagen might explain. Also, the stratum arrangement of the muscularis might explain mechanical anisotropy during tensile tests. This study shows that gastric tissue is characterized by a highly heterogeneous microstructure with regional variations in layer composition reflecting not only functional differences but also diverse mechanical behavior. Statement of SignificanceUnfortunately, only few experimental data on gastric tissue are available for an adequate material parameter and model estimation. The present study therefore combines layer- and region-specific stomach wall mechanics obtained under multiple loading conditions with histological insights into the heterogeneous microstructure. On the one hand, the extensive data sets of this study expand our understanding of the interplay between gastric mechanics, motility and functionality, which could help to identify and treat associated pathologies. On the other hand, such data sets are of high relevance for the constitutive modeling of stomach tissue, and its application in the field of medical engineering, e.g., in the development of surgical staplers and the improvement of bariatric surgical interventions.

Mucoadhesive capsules based on bacterial nanocellulose and chitosan as delivery system of turmeric extract

Current efforts in stomach-related drug design focus on improving drug bioavailability within the gastric region. Bacterial nanocellulose (BNC) has been established as a suitable material for drug delivery systems; however, it lacks adhesion to the gastric environment. This limitation can be addressed by leveraging the mucoadhesive properties of low molecular weight chitosan (LMWC). Therefore, we aimed to develop mucoadhesive capsules constructed from BNC coated with crosslinked LMWC, intended for targeted drug delivery in the gastric region. The capsules were characterized using scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and mucoadhesion assessments. Under acidic conditions, crosslinked chitosan exhibited enhanced swelling relative to neutral conditions. The coating of chitosan onto the BNC fibrillar network of the capsules resulted in the superimposition of vibration bands and enhanced thermal stability. Furthermore, the capsules exhibited significant mucoadhesive properties in the gastric environment, with an attachment force measuring 89.151 ± 6.226 mN. To validate the efficacy of the system, we utilized antioxidant turmeric extract (TE) as a bioactive compound with chemopreventive potential against stomach cancer. TE was adsorbed onto BNC in a reversible multilayer system, enabling controlled adsorption and desorption. These findings highlight the significance of developing mucoadhesive capsules as a tailored drug delivery system for gastric conditions, particularly in the context of treating stomach diseases as cancer.

Study on arsenic speciation, bioaccessibility, and gut microbiota in realgar-containing medicines by DGT technique and artificial gastrointestinal extraction (PBET) combine with simulated human intestinal microbial ecosystem (SHIME)

It is well-known that several Chinese patent medicines use realgar as a specific component. People are more aware of the health dangers associated with realgar since it includes arsenic. Previous research overstated the arsenic toxicity of realgar-containing Chinese prescription medications because little thought was given to the influence of arsenic bioaccessibility by gut microbiota. In light of this, this study examined the total content, bioaccessibility and speciation of targeted medications while also examining intestinal epithelial transit utilizing the diffusive gradients in thin-films (DGT). All samples contained arsenic, and the bioaccessibilities of the colon, intestine and gastric regions ranged from 0.19% to 1.73%, 0.25–1.88% and 0.21–1.70% respectively. The range of DGT-bioaccessibility is 0.01–0.0018%. Three steps of analysis were conducted on inorganic As(III) and As(V). In health risk assessment, the ADDs and HQs of DGT-bioaccessibility were below the threshold levels when compared to computing average daily intake dose (ADD) and hazard quotient (HQ) by bioaccessibility of gastric, intestinal and colon. Additionally, Proteobacteria and Firmicutes were discovered to be the two predominant kinds of gut microbes in this study. Under arsenic exposure, the abundance of Christensenellaceae, Desulfovibrionaceae and Akkermansiaceae increased, but the quantity of Rikenellaceae decreased. These findings revealed that alterations in gut microbiota had an impact on host metabolism.

Patients with postprandial distress syndrome experience problems with their interoceptive perceptual function to the gastric region, but their heartbeat perception is normal: a case control study

BackgroundVisceral hypersensitivity in functional dyspepsia can be localized or widespread, and there is no simple method of assessment. Measuring interoceptive accuracy at different sites provides an assessment of perceptual hypersensitivity to specific ecological phenomena. The purpose of this study was to characterize visceral hypersensitivity by comparing gastric sensory and cardiac perceptual tests in patients with postprandial distress syndrome and in healthy volunteers.MethodsSixteen patients with postprandial distress syndrome (age = 47.5 ± 17.4, all female) and 16 healthy volunteers (age = 43.3 ± 16.1, all female) participated in the study after a six-hour fast. Each participant answered questionnaires about physical and mental quality of life, depression and anxiety, tendency of alexithymia, and somatosensory amplification. After completing the questionnaire, the participants took the heartbeat tracking task and the five-minute water load test. We performed statistical analysis using the Mann–Whitney U test and Spearman’s rank correlation coefficient.ResultsSubjects with postprandial distress syndrome had a lower drinking capacity than healthy volunteers (postprandial distress syndrome = 360.9 ± 170.0 mL, healthy volunteers = 644.1 ± 297 mL, P = 0.009), but there was no significant difference in the heartbeat perception score (postprandial distress syndrome = 0.599 ± 0.175, healthy volunteers = 0.623 ± 0.181, P = 0.647). There was a negative correlation (r = − 0.509, P < 0.05) between drinking capacity and the heartbeat perception score in healthy volunteers, but no correlation in postprandial distress syndrome (r = − 0.156, P = 0.564). Heartbeat perception score did not correlate with psychological measures.ConclusionsCompared with healthy volunteers, only the five-minute water load test values were reduced in patients with postprandial distress syndrome, and no difference was observed in the heartbeat tracking task. Combining the 5-minute water load test and the heart rate tracking task revealed a lost cardiac-gastric perceptual relationship in patients with postprandial distress syndrome that was not observed in healthy volunteers, suggesting that there is hypersensitivity in gastric interoceptive perceptual function. Performing sensory examinations at two different sites may be useful in clarifying whether visceral hypersensitivity is localized.Trial registrationUMIN000057586. Registered11 March 2023(retrospectively registered).

Mechanosensitive enteric neurons in the guinea pig gastric fundus and antrum.

Coping with the ingested food, the gastric regions of fundus, corpus, and antrum display different motility patterns. Intrinsic components of such patterns involving mechanosensitive enteric neurons (MEN) have been described in the guinea pig gastric corpus but are poorly understood in the fundus and antrum. To elucidate mechanosensitive properties of myenteric neurons in the gastric fundus and antrum, membrane potential imaging using Di-8-ANEPPS was applied. A small-volume injection led to neuronal compression. We analyzed the number of MEN and their firing frequency in addition to the involvement of selected mechanoreceptors. To characterize the neurochemical phenotype of MEN, we performed immunohistochemistry. In the gastric fundus, 16% of the neurons reproducibly responded to mechanical stimulation and thus were MEN. Of those, 83% were cholinergic and 19% nitrergic. In the antrum, 6% of the neurons responded to the compression stimulus, equally distributed among cholinergic and nitrergic MEN. Defunctionalizing the sensory extrinsic afferents led to a significant drop in the number of MEN in both regions. We provided evidence for MEN in the gastric fundus and antrum and further investigated mechanoreceptors. However, the proportions of the chemical phenotypes of the MEN differed significantly between both regions. Further investigations of synaptic connections of MEN are crucial to understand the hardwired neuronal circuits in the stomach.

Simultaneous Colonic Pressure Waves in Children and Young Adults with Gastrointestinal Motility Disorders: Artefact or Colonic Physiology?

Simultaneous pressure waves (SPW) spanning all recording sites in colonic manometry studies have been described as a potential biomarker of normal gas transit and extrinsic neural reflexes. In pediatric studies utilizing combined antroduodenal and colonic manometry, it was noted that most colonic SPWs appeared to also span all sensors in the gastric and small bowel regions. This suggests that a proportion of colonic SPWs may represent an artefact caused by forces extrinsic to the colon. Our aim was to characterize colonic SPWs and determine how many of these spanned most of the digestive tract. In 39 combined high-resolution antroduodenal and colonic manometry traces from 27 pediatric patients, we used our purpose-built software to identify all SPWs that spanned either (i) all recording sites in the digestive tract or (ii) those restricted to the colon. A total of 14,565 SPWs were identified (364 ± 316 SPWs/study), with 14,550 (99.9%) spanning the entire antroduodenal and colonic recording sites. Only 15 SPWs (0.1% of the total) were restricted to the colon (all in one recording). Based on these findings, we suggest that, in pediatric studies, SPWs should not form part of any diagnostic criteria, as these events appear to be an artefact caused by factors outside the colon (abdominal strain, body motion).

New and rare deep-sea majoid crabs (Crustacea: Brachyura) from Papua New Guinea.

Additional spider crab (superfamily Majoidea) material from four major French-led expeditions to the Papua New Guinea region were examined in this study. One new genus and four new species from the families Inachidae and Oregoniidae are described. Dorhynchus profundus n. sp. is close to D. rostratus (Sakai, 1932) but can easily be separated by the shape of the ambulatory dactylus and the proportionately lower protogastric spines. Achaeus pholcus n. sp. is unusual in that it occurs in deeper waters (beyond 500 m), and can be separated from A. lacertosus Stimpson, 1857, A. villosus Rathbun, 1916, and A. brevidactylus Sakai, 1938, by its distinctive carapace shape, structure of the frontal margin, regions of the carapace, antennular fossa, ambulatory dactylus, male pleon, and proportions of the chela. Parapleisticantha aie n. sp. is closest to P. japonica Yokoya, 1933, but differs in its proportionately longer carapace, more elongated basal antennal article, longer third maxilliped ischium and the relatively less curved male first gonopod with the distal part differently structured. A new genus (Orbicantha n. gen.) with one new species (Orbicantha sacrebleu n. gen., n. sp.) is also described; it is allied to Pleistacantha Miers, 1879, Parapleisticantha Yokoya 1933, and Pleisticanthoides Yokoya, 1933, but is distinctive in its subcircular carapace, shorter regions, short pseudorostral spines, possession of spines on the gastric, cardiac and branchial regions, some of which have rounded tips, a short ocular peduncle, a very short third antennal article, a quadrate epistome, and the more reduced P4 and P5. New records from the family Epialtidae are also reported: Griffinia gilloloensis (Rathbun, 1916), Hyastenus borradailei (Rathbun, 1907), and Oxypleurodon luzonicum (Rathbun, 1916). The taxonomy of Grypachaeus tenuicollis Takeda, 1978 (Oregoniidae) and Griffinia lappacea (Rathbun, 1918) (Epialtidae) is also discussed.

Structural Features of the Cardia Gastric Region in Domestic Rabbits

The knowledge of normal microscopical peculiarities of the digestive system in mammals is essential, but information regarding certain structures is still scarce in numerous species. Our study aims to highlight the normal morphological features of the cardia region in domestic rabbits, as regards the overall appearance, structure, and dimensions of the gastric pits, including a description of the cells located in gastric glands. The cardia region of five domestic rabbits underwent tissue sampling, followed by fixation in 10% buffered formalin, paraffin embedding, and later sectioned at 5 µm in thickness. Eventually, the samples were stained by Goldner’s trichrome method. The microscopical examination has revealed the presence of gastric pits and glands in the entire cardia region of the rabbit, with a different morphological appearance from one zone to another. Gastric pits have the smallest depth immediately after the oesophagogastric junction, which gradually increases and decreases afterwards as it approaches the fundic zone. The gastric glands contain basically four cell types in various proportions, including serous cells, mucous cells, parietal cells, and chief cells. Other peculiarities of the gastric mucosa in the cardia region in rabbits include a thick mucosa with a loose and prominent lamina propria, and an ill-defined muscularis mucosae that is not organized in distinct layers as in other species. The detailed microanatomical structure of the cardia region of the stomach is necessary for understanding the digestion processes in rabbits, species used as a model in diverse fields of research including the pathology of the digestive system.