Structural and tribological studies on the interaction of porcine gastric mucin with non- and cationic-modified ß-lactoglobulins.

ß-lactoglobulin (BLG) is the major whey protein with negative charges at neutral pH in aqueous media. Thus, the interaction with mucins, the major polyanionic component of mucus, is very weak due to the electrostatic repulsion between them. The present study postulates that cationization of BLG molecules may reverse the interaction characteristics between BLG and mucin from repulsive to associative. To this end, cationic-modified BLGs were prepared by grafting positively charged ethylenediamine (EDA) moieties into the negatively charged carboxyl groups on the aspartic and glutamic acid residues and compared with non-modified BLG upon mixing with porcine gastric mucin (PGM). To characterize the structural and conformational features of PGM, non/cationized BLGs, and their mixtures, various spectroscopic approaches, including zeta potential, dynamic light scattering (DLS), and circular dichroism (CD) spectroscopy were employed. Importantly, we have taken surface adsorption with optical waveguide lightmode spectroscopy (OWLS), and tribological properties with pin-on-disk tribometry at the sliding interface as the key approaches to determine the interaction nature between them as mixing PGM with polycations can lead to synergistic lubrication at the nonpolar substrate in neutral aqueous media as a result of an electrostatic association. All the spectroscopic studies and a substantial improvement in lubricity collectively supported a tenacious and associative interaction between PGM and cationized BLGs, but not between PGM and non-modified BLG. This study demonstrates a unique and successful approach to intensify the interaction between BLG and mucins, which is meaningful for a broad range of disciplines, including food science, macromolecular interactions, and biolubrication etc.

Examining the efficiency of porcine gastric mucin-coated magnetic beads in extraction of noroviruses from frozen berries.

Human norovirus is the leading cause of foodborne gastroenteritis worldwide. Due to the low infectious dose of noroviruses, sensitive methodologies are required to detect and characterize small numbers of viral particles that are found in contaminated foods. The ISO 15216 method, which is internationally recognized for detection of foodborne viruses from high-risk food commodities, is based on viral precipitation, followed by RNA extraction and identification of the viral genome by RT-PCR. Although the ISO 15216 method is efficient, it is time consuming and tedious, does not report on the viral infectivity, and is sensitive to the presence of RT-PCR inhibitors. Norovirus capture by the porcine gastric mucin conjugated magnetic beads (PGM-MB) was developed as an alternative virus recovery method. It relies on the integrity of the viral capsid being able to bind to PGM. PGM contains a variety of histo-blood group antigens (HBGAs) that act as norovirus receptors. Therefore, the PGM-MB method allows for extraction of noroviruses, with potentially intact viral capsids, from complex food matrices. The viral genome can then be released through heat-shock of the captured virus. For this reason, we performed a parallel comparison between the ISO 15216 method and the PGM-MB method in isolation and quantification of noroviruses from frozen raspberries. We have demonstrated that the efficiency of the PGM-MB method in extraction of murine norovirus (MNV) and human norovirus GII.4 from raspberries is equal or better than the ISO 15216 method, while the PGM-MB has fewer steps and shorter turnaround time. Moreover, the PGM-MB method is more efficient in removing the inhibitors prior to RT-PCR analysis.

Chitosan interaction with stomach mucin layer to enhances gastric retention and mucoadhesive properties.

The interaction between mucoadhesive materials and mucin layers is of significant interest in the development of drug delivery systems and biomedical applications for effective targeting and prolonged stay in the gastrointestinal tract. In this article, the current advancement and mucoadhesive properties of chitosan concerning the stomach mucin layer and its interactions have been briefly addressed. Chitosan a biocompatible polysaccharide exhibited promising mucoadhesive properties attributed to its cationic nature and ability to establish bonds with mucin glycoproteins. The mucoadhesion mechanism is ascribed to the electrostatic interactions between the positively charged amino (NH2) groups of chitosan and the sialic acid residues in mucin glycoprotein which carry a negative charge. The article provides a succinct overview of prior uses, current trends, and recent advancements in chitosan-based gastric-targeted delivery systems. We look forward to further innovations and emerging research related to chitosan-based methods of delivery that may increase the chitosan suitability for use in novel therapeutic approaches.

Extraction and Fractionation of Human Gastric Mucins from Gastric Juice.

Mucin, a major component of the mucus, is considered to be one of the principal factors in the physiological defense mechanism of the gastrointestinal mucosa. Measuring the mucin content of human gastric mucus is a useful tool for the assessment of Helicobacter pylori (H. pylori) eradication or the involvement of mucus secretion in various gastroduodenal diseases. Here, we describe a methodology for the isolation of the mucin fraction from human gastric juice and the quantification of mucin.

On the mucoadhesive properties of synthetic and natural polyampholytes.

HYPOTHESIS: The mucoadhesive characteristics of amphoteric polymers (also known as polyampholytes) can vary and are influenced by factors such as the solution's pH and its relative position against their isoelectric point (pHIEP). Whilst the literature contains numerous reports on mucoadhesive properties of either cationic or anionic polymers, very little is known about these characteristics for polyampholytes EXPERIMENTS: Here, two amphoteric polymers were synthesized by reaction of linear polyethylene imine (l-PEI) with succinic or phthalic anhydride and their mucoadhesive properties were compared to bovine serum albumin (BSA), selected as a natural polyampholyte. Interactions between these polymers and porcine gastric mucin were studied using turbidimetric titration and isothermal titration calorimetry across a wide range of pHs. Model tablets were designed, coated with these polymers and tested to evaluate their adhesion to porcine gastric mucosa at different pHs. Moreover, a retention study using fluorescein isothiocyanate (FITC)-labelled polyampholytes deposited onto mucosal surfaces was also conducted FINDINGS: All these studies indicated the importance of solution pH and its relative position against pHIEP in the mucoadhesive properties of polyampholytes. Both synthetic and natural polyampholytes exhibited strong interactions with mucin and good mucoadhesive properties at pH < pHIEP.

Kinesin Family Member B18 Is Related to Gastric Mucin Phenotype and Contributes to Gastric Cancer Progression by Regulating Epithelial-Mesenchymal Transition.

INTRODUCTION: Gastric cancer (GC) remains a common health concern worldwide and is the third leading cause of death in Japan. It can be broadly classified into gastric and intestinal mucin phenotypes using immunohistochemistry. We previously reported numerous associations of kinesin family member (KIF) genes and mucin phenotypes with GC. However, no previous studies have reported on the importance of KIF18B in GC using immunostaining. Thus, in this study, we investigated the expression and functions of KIF18B, which is highly expressed in gastric mucin phenotype GC. METHODS: We performed RNA-seq of gastric and intestinal mucin type GCs, and clinicopathological studies of the KIF18B we found were performed using 96 GC cases. We also performed functional analysis using GC-derived cell lines. RESULT: RNA-seq showed the upregulation of matrisome-associated genes in gastric mucin phenotype GC and a high expression of KIF18B. KIF18B was detected in 52 of the 96 GC cases (54%) through immunohistochemistry. Low KIF18B expression was significantly associated with poor overall survival (p < 0.01). Other molecules that were significantly associated with KIF18B were MUC5AC and claudin 18; these were also significantly associated with the gastric mucin phenotype. KIF18B small interfering RNA (siRNA)-transfected GC cells showed greater growth and spheroid colony formation than the negative control siRNA-transfected cells. Furthermore, expression of snail family transcriptional repressor 1 and cadherin 2 was significantly increased and that of cadherin 1 was significantly decreased in KIF18B siRNA-transfected GC cells. CONCLUSION: These findings not only suggest that KIF18B may be a useful prognostic marker, but also provide insight into the pathogenesis of the GC phenotype.

Priestia flexa KS1: A new bacterial strain isolated from human faeces implicated in mucin degradation / Priestia flexa KS1: Una nueva cepa bacteriana aislada de heces humanas implicada en la degradación de la mucina

The human gut acts as a habitat for diverse microbial communities, including mucin utilizers that play a significant role in host health and diseases. In this study, a gram-positive, rod-shaped mucin degrading bacterium was isolated from human faeces that belonged to the Priestia flexa species. Priestia isolate was analyzed for mucin-degrading ability and found that the KS1 strain could grow on mucin as the sole carbon source. The experimental results of the mucolytic zone around the colony and a 58% decrease in carbohydrate concentration confirmed the ability of Priestia to degrade mucin. The intracellular and extracellular glycosidase assay data supported the above results suggesting the ability of P. flexa to produce glycan hydrolysis enzymes that convert complex mucin oligosaccharide chains into simple glycans. The survival ability of the KS1 strain in simulated gastrointestinal conditions revealed that it could tolerate low pH (≥ 50% cell viability at pH 1.0) and 0.5% bile salt concentration (≥ 85% cell viability). The strain showed low hydrophobicity towards n-hexadecane (26.51 ± 0.92%) and xylene (21.71 ± 0.54%). Moreover, the KS1 culture was resistant to cefixime, clavulanic acid/ceftazidime, nafallin, methicillin, trimethoprim, kanamycin, and nalidixic antibiotic. Our results highlight the isolation of P. flexa KS1 strain that degrade mucin under in vitro conditions and show its better acclimatization within the GI environment. Further studies are required to unearth the molecular mechanisms involved in the degradation of mucin oligosaccharides in the human gut, advancing our understanding of health and disease.(AU)

A Complex Connection Between the Diversity of Human Gastric Mucin O-Glycans, Helicobacter pylori Binding, Helicobacter Infection and Fucosylation.

Helicobacter pylori colonizes the stomach of half of the human population. Most H. pylori are located in the mucus layer, which is mainly comprised by glycosylated mucins. Using mass spectrometry, we identified 631 glycans (whereof 145 were fully characterized and the remainder assigned as compositions) on mucins isolated from 14 Helicobacter spp.-infected and 14 Helicobacter spp.-noninfected stomachs. Only six identified glycans were common to all individuals, from a total of 60 to 189 glycans in each individual. An increased number of unique glycan structures together with an increased intraindividual diversity and larger interindividual variation were identified among O-glycans from Helicobacter spp.-infected stomachs compared with noninfected stomachs. H. pylori strain J99, which carries the blood group antigen-binding adhesin (BabA), the sialic acid-binding adhesin (SabA), and the LacdiNAc-binding adhesin, bound both to Lewis b (Leb)-positive and Leb-negative mucins. Among Leb-positive mucins, H. pylori J99 binding was higher to mucins from Helicobacter spp.-infected individuals than noninfected individuals. Statistical correlation analysis, binding experiments with J99 wt, and J99ΔbabAΔsabA and inhibition experiments using synthetic glycoconjugates demonstrated that the differences in H. pylori-binding ability among these four groups were governed by BabA-dependent binding to fucosylated structures. LacdiNAc levels were lower in mucins that bound to J99 lacking BabA and SabA than in mucins that did not, suggesting that LacdiNAc did not significantly contribute to the binding. We identified 24 O-glycans from Leb-negative mucins that correlated well with H. pylori binding whereof 23 contained α1,2-linked fucosylation. The large and diverse gastric glycan library identified, including structures that correlated with H. pylori binding, could be used to select glycodeterminants to experimentally investigate further for their importance in host-pathogen interactions and as candidates to develop glycan-based therapies.

Biology and management of lobular endocervical glandular hyperplasia.

AIM: Lobular endocervical glandular hyperplasia (LEGH) is a multicystic proliferative disorder of the uterine cervix. The aim of this review was to clarify the current understanding of this unique tumor. METHOD: This article reviews the chronological progress of research regarding clinico-pathological and genetic aspects of LEGH and related cervical cystic diseases such as Nabothian cyst and adenocarcinoma of gastric type (GAS), using the literature and data from our institute. We also describe clinical management including preoperative diagnosis and adequate surgical/expectant treatment based on the biological features. RESULTS: Recent studies revealed several unique aspects of LEGH, that is, (i) production of gastric mucin, (ii) symptomatic and histological similarity with minimal deviation adenocarcinoma (MDA), and (iii) frequent association with GAS, including MDA. These findings indicated that LEGH is a gastric metaplasia, as well as pre-cancerous neoplasia. For the preoperative diagnosis of LEGH, the combination of "cosmos" sign on magnetic resonance imaging, detection of gastric mucin, and lack of nuclear atypia on cytology is important. Cone biopsy is effective for pathological diagnosis. Simple hysterectomy is indicated as surgical treatment for LEGH; however, meticulous follow-up is also an option, especially for young patients, because the rate of malignant transformation was reported to be 1%-2%. For LEGH patients who selected follow-up, a worsening cytology and increase in lesion size were important signs of malignant change of LEGH for safe follow-up. CONCLUSION: Proper understanding of the characteristics of LEGH is important for adequate management.

α1,4-Linked N-acetylglucosamine suppresses gastric cancer development by inhibiting Mucin-1-mediated signaling.

Gastric cancer is the second leading cause of cancer deaths worldwide, and more understanding of its molecular basis is urgently needed. Gastric gland mucin secreted from pyloric gland cells, mucous neck cells, and cardiac gland cells of the gastric mucosa harbors unique O-glycans carrying terminal α1,4-linked N-acetylglucosamine (αGlcNAc) residues. We previously reported that αGlcNAc loss correlated positively with poor outcomes for patients with differentiated-type gastric cancer. However, the molecular mechanisms underlying these outcomes remained poorly understood. Here, we examined the effects of upregulated αGlcNAc expression on malignant phenotypes of the differentiated-type gastric cancer cell lines, AGS and MKN7. Upregulation of αGlcNAc following ectopic expression of its biosynthetic enzyme attenuated cell proliferation, motility, and invasiveness of AGS and MKN7 cells in vitro. Moreover, AGS cell tumorigenicity was significantly suppressed by αGlcNAc overexpression in a xenograft model. To define the molecular mechanisms underlying these phenotypes, we investigated αGlcNAc binding proteins in AGS cells and identified Mucin-1 (MUC1) and podocalyxin. Both proteins were colocalized with αGlcNAc on human gastric cancer cells. We also found that αGlcNAc was bound to MUC1 in murine normal gastric mucosa. When we assessed the effects of αGlcNAc binding to MUC1, we found that αGlcNAc blocked galectin-3 binding to MUC1, phosphorylation of the MUC1 C-terminus, and recruitment of Src and ß-catenin to that C-terminus. These results suggest that αGlcNAc regulates cancer cell phenotypes by dampening MUC1 signal transduction.

MUC6 expression is a preferable prognostic marker for invasive mucinous adenocarcinoma of the lung.

Gastric gland mucin consists of core protein MUC6 with residues heavily glycosylated by unique O-glycans carrying α1,4-linked N-acetylglucosamine (αGlcNAc). αGlcNAc-glycosylated MUC6 protein is seen in normal gastric and duodenal glands. Decreased αGlcNAc glycosylation on MUC6-positive tumor cells is often observed in premalignant lesions of the stomach, pancreas, and bile duct, and decreased MUC6 expression is seen in invasive cancer of these organs. Lung cancer (LC) is the most common cause of cancer death worldwide. Recently, the adenocarcinoma subtype has become the most common histological subtype of LC, and one of its invasive forms is invasive mucinous adenocarcinoma (IMA). Currently, prognostic markers of LC IMA are unknown. Here, we analyzed MUC5AC, MUC6, and αGlcNAc expression in 54 IMA LC cases. MUC5AC was positively expressed in 50 (93%), MUC6 in 38 (70%), and αGlcNAc in 19 (35%). Each expression level was scored from 0 to 3. The αGlcNAc expression score was significantly decreased relative to MUC6 (P < 0.001). Interestingly, disease-free survival was significantly higher in MUC6-positive than MUC6-negative cases based on the log-rank test (P = 0.021). For in vitro analysis, we ectopically expressed MUC6 in A549 cells, derived from LC and harboring a KRAS mutation. MUC6-expressing A549 cells showed significantly lower proliferation, motility, and invasiveness than control cells. Finally, F-actin staining in MUC6-expressing cells revealed a decrease or loss of filopodia associated with decreased levels of FSCN transcripts, which encodes an actin-bundling protein fascin1 necessary for cell migration. We conclude that MUC6 expression is a preferable prognostic biomarker in IMA LC.

Complexation between porcine gastric mucin (PGM) and lysozyme: Influence of heat treatment of lysozyme on the tribological properties.

The influence of complexation between porcine gastric mucin (PGM) and lysozyme (LYZ) solutions (pH⁓7.0) on their lubricating properties was studied at a hydrophobic self-mated polydimethylsiloxane (PDMS) tribopair. To this end, LYZ solutions with varying heating time, namely 1hr, 3hr-, and 6hr at 90 °C, as well as unheated LYZ solution, were prepared. The lubricating capability of PGM and LYZ solutions and also their mixtures was characterized using pin-on-disk tribometry. In parallel, to precisely investigate the interaction between PGM and LYZ solutions, an array of the well-known experiments including electrophoretic-dynamic light scattering, circular dichroism spectroscopy and optical waveguide light-mode spectroscopy were employed. These experiments were utilized to elucidate the key features e.g. zeta potential, hydrodynamic diameter, conformational structure and mass adsorption. The tribometry results indicated that both PGM and unheated LYZ solutions had poor lubricating properties in the boundary lubrication regime (sliding speed lower than 10 mm/s). Mixing PGM with unheated LYZ led to a slight decrease in the friction coefficient, but no desirable lubricity was observed. An optimum slippery characteristic was achieved by incorporating 1hr heated LYZ solution into PGM one. Excellent lubricity of PGM/1hr heated LYZ may stem from surface charge compensation, tenaciously compact aggregation, unique conformational structure and considerable mass adsorption onto PDMS. This finding revealed that a strong interaction between PGM and LYZ molecules and as a result, the promising lubricating capability of PGM/LYZ mixtures, can be administered by varying heat-treatment duration of LYZ proteins.

Covalently Cross-Linked Pig Gastric Mucin Hydrogels Prepared by Radical-Based Chain-Growth and Thiol-ene Mechanisms.

Mucin, a high molecular mass hydrophilic glycoprotein, is the main component of mucus that coats every wet epithelium in animals. It is thus intrinsically biocompatible, and with its protein backbone and the o-glycosidic bound oligosaccharides, it contains a plethora of functional groups which can be used for further chemical modifications. Here, chain-growth and step-growth (thiol-ene) free-radical cross-linked hydrogels prepared from commercially available pig gastric mucin (PGM) are introduced and compared as cost-efficient and easily accessible alternative to the more broadly applied bovine submaxillary gland mucin. For this, PGM is functionalized with photoreactive acrylate groups or allyl ether moieties, respectively. Whereas homopolymerization of acrylate-functionalized polymers is performed, for thiol-ene cross-linking, the allyl-ether-functionalized PGM is cross-linked with thiol-functionalized hyaluronic acid. Morphology, mechanical properties, and cell compatibility of both kinds of PGM hydrogels are characterized and compared. Furthermore, the biocompatibility of these hydrogels can be evaluated in cell culture experiments.

Interactions of ß-Lactoglobulin with Bovine Submaxillary Mucin vs. Porcine Gastric Mucin: The Role of Hydrophobic and Hydrophilic Residues as Studied by Fluorescence Spectroscopy.

The aim of this study was to investigate binding interactions between ß-lactoglobulin (BLG) and two different mucins, bovine submaxillary mucins (BSM) and porcine gastric mucin (PGM), using intrinsic and extrinsic fluorescence spectroscopies. Intrinsic fluorescence spectra showed an enhanced decrease of fluorescence intensity of BLG at all pH conditions when BLG was mixed with PGM rather than with BSM. We propose that, unlike BSM, the tertiary structure of PGM changes and the hydrophobic regions are exposed at pH 3 due to protonation of negatively charged residues. Results suggest that PGM also facilitated the structural unfolding of BLG and its binding with PGM by a hydrophobic interaction, especially at acidic pH, which was further supported by extrinsic fluorescence spectroscopy. Hydrophobic interaction is suggested as the dominant interaction mechanism between BLG and PGM at pH 3, whereas electrostatic interaction is the dominant one between BLG and BSM.

A survival comparison of gastric mucin-producing adenocarcinoma to conventional adenocarcinoma: a SEER database analysis.

BACKGROUND: Compared to conventional adenocarcinoma (CA), mucin-producing adenocarcinoma (MPA) is an uncommon histological subtype and is usually separated from other histological types and has been evaluated separately. The objective was to compare the clinicopathological characteristics and survivals of MPA with CA. METHODS: We retrospectively analyzed 1515 MPA patients in SEER database. Log-rank tests and KM survival curves were applied to determine the differences in overall survival (OS) and cancer specific survival (CSS) time. RESULTS: No significant differences were noted in OS and CSS time. The MPA patients who were treated with surgery and chemotherapy exhibited longer OS and CSS time periods than those without treatment. MPA patients treated with radiotherapy exhibited similar OS and CSS time with those without radiotherapy. MPA was not a prognostic factor of survival. CONCLUSIONS: MPA was a rare histological type of gastric cancer. Patients with MPA exhibited similar prognosis with those with CA. Surgery and chemotherapy were effective treatments for patients with MPA.

Atractylenolide­1 alleviates gastroparesis in diabetic rats by activating the stem cell factor/c­kit signaling pathway.

Diabetic gastroparesis (DGP), also known as delayed gastric emptying, is a common complication of diabetes mellitus. There are numerous clinical symptoms associated with DGP, as well as high treatment costs and markedly reduced patient quality of life. However, the pathogenesis of DGP is not clear, thus effective treatment methods are yet to be established. In the present study, a DGP rat model was established in Sprague­Dawley rats by the intraperitoneal injection of streptozotocin (STZ). DGP model rats were treated with different doses of atractylenolide­1 to detect alterations in gastrointestinal function, including gastroparesis, gastric emptying, gastric motility, gastric peristalsis and gastric blood flow. Compared with the DGP group, atractylenolide­1 treatment significantly reduced glycaemia and the level of glycated hemoglobin, as well as restoring gastrointestinal function. Gastroparesis, gastric emptying, gastric motility, gastric peristalsis and gastric blood flow were significantly impaired in the STZ­induced group compared with the vehicle control group. Moreover, the STZ­induced group displayed downregulated expression levels of the DGP indicator KIT proto­oncogene, receptor tyrosine kinase (c­kit), as investigated by immunohistochemistry, and stem cell factor (SCF) protein, as assessed using ELISA, significantly enhanced rat interstitial cells of Cajal (ICC) apoptosis, and significantly altered levels of oxidative stress­related markers (malondialdehyde and superoxide dismutase) in the serum and gastric tissues compared with the vehicle control group. By contrast, treatment with atractylenolide­1 significantly counteracted the effects of DGP on peristalsis, inhibited apoptosis and suppressed oxidative stress by regulating the expression of heme oxygenase 1 in STZ­induced DGP model rats. Further research indicated that atractylenolide­1 regulated oxidative stress reactions and improved gastric function by activating the SCF/c­kit signaling pathway. Collectively, the results of the present study suggested that atractylenolide­1 promoted ICC survival and preserved the structure of the gastric tissue network in a DGP rat model via the SCF/c­kit signaling pathway, providing novel insights for the treatment of DGP.

Gastric mucin phenotype indicates aggressive biological behaviour in early differentiated gastric adenocarcinomas following endoscopic treatment.

BACKGROUND: The distribution of mucin phenotypes and their relationship with clinicopathological features in early differentiated gastric adenocarcinomas in a Chinese cohort are unknown. We aimed to investigate mucin phenotypes and analyse the relationship between mucin phenotypes and clinicopathological features, especially biological behaviours, in early differentiated gastric adenocarcinomas from endoscopic specimens in a Chinese cohort. METHODS: Immunohistochemical staining of CD10, MUC2, MUC5AC, and MUC6 was performed in 257 tissue samples from patients with early differentiated gastric adenocarcinomas. The tumour location, gross type, tumour size, histological type, depth of invasion, lymphovascular invasion, mucosal background and other clinicopathological parameters were evaluated. The relationship between mucin phenotypes and clinicopathological features was analysed with the chi-square test. RESULTS: The incidences of gastric, gastrointestinal, intestinal and null phenotypes were 21 %, 56 %, 20 and 3 %, respectively. The mucin phenotypes were related to histology classification (P < 0.05). The proportion of the gastric phenotype became greater during the transition from differentiated to undifferentiated (P < 0.05). Complete intestinal metaplasia was higher in the gastric and intestinal phenotypes than in the gastrointestinal phenotype (P < 0.05). Tumours with poorly differentiated adenocarcinoma were mainly of the gastric phenotype, which was significantly higher than that of purely differentiated tubular adenocarcinoma (P < 0.05), and the depth of invasion in the mixed type was deeper (P < 0.05). Neither recurrence nor metastasis was detected. CONCLUSIONS: The mucin phenotype of early-differentiated gastric adenocarcinoma has clinical implications, and the gastric phenotype has aggressive biological behaviour in early differentiated gastric cancers, especially in those with poorly differentiated adenocarcinoma or papillary adenocarcinoma components.

Taxifolin and gastro-adhesive microparticles containing taxifolin promotes gastric healing in vivo, inhibits Helicobacter pylori in vitro and proton pump reversibly in silico.

Taxifolin (3,5,7,3,4-pentahydroxy flavanone or dihydroquercetin, Tax) was identified as a gastroprotective compound and a gastroadhesive formulation was recently developed to prolong its residence time and release in the stomach. So, the gastric healing effectiveness of Tax and gastro-mucoadhesive microparticles containing Tax (MPTax) against the acetic acid induced-gastric ulcer in rats was investigated in this study. Moreover, the interactions between Tax and H+/K+-ATPase were investigated in silico, and its anti- H. pylori activity was determined in vitro. The oral treatment with MPTax (81.37 mg/kg, containing 12.29% of Tax) twice a day for seven days reduced the ulcer area by 63%, compared to vehicle-treated group (Veh: 91.9 ± 10.3 mm2). Tax (10 mg/kg, p.o) reduced the ulcer by 40% but with a p = 0.07 versus Veh group. Histological analysis confirmed these effects. Tax and MPTax increased the gastric mucin amount, reduced the myeloperoxidase activity, and increased the glutathione reduced content at ulcer site. However, only MPTax decreased the lipoperoxide accumulation at ulcer site. Besides, Tax and MPTax normalize the catalase and glutathione S-transferase activity. Tax showed reversible interaction with H+/K+-ATPase in silico and its anti-H. pylori effects was confirmed (MIC = 625 µg/mL). These results suggest that the antiulcer property of Tax involves the strengthening of the gastric protective factors in parallel to its inhibitory interaction with H+/K+-ATPase and H. pylori. Considering that ulcer healing action displayed by Tax was favored by gastroadhesive microparticles, this approach seems to be promising for its oral delivery to treat acid-peptic diseases.

Usefulness of the 'cosmos pattern' for differentiating between cervical gastric-type mucin-positive lesions and other benign cervical cystic lesions in magnetic resonance images.

AIM: To evaluate the usefulness of the 'cosmos pattern' (CP) on magnetic resonance (MR) images for differentiating between gastric-type mucin-positive lesions (GMPL) and gastric-type mucin-negative lesions (GMNL). METHODS: This study included 131 patients with clinical suspicion of lobular endocervical glandular hyperplasia (LEGH) who underwent pelvic MR imaging and a Pap smear and/or latex agglutination assay. Differences in MR findings, such as cyst and solid component patterns, cervical location and T1-weighted image (T1WI) signal intensity, were compared between GMPL and GMNL. The diagnostic performances of the findings were assessed. RESULTS: The frequencies of CP (63.1%), upper part (UP) lesions (72.3%) and hypointense area compared with the cervical stroma on T1WI (61.3%) were significantly greater in GMPL than in GMNL (P < 0.05). The sensitivity, specificity, positive predictive value, negative predictive value and odds ratio of the CP for diagnosis of GMPL were 63.1%, 87.9%, 83.7%, 70.7% and 12.4, respectively. In GMNL, a 'macrocystic pattern' was observed in 65.2% of patients; an isointense or hyperintense area on T1WI was observed in 86.4% of patients. The sensitivity was highest (90.8%) when one or more of the following were observed: CP, UP lesion, or hypointense area on T1WI. The specificity was highest (95.5%) when the CP was observed as a hypointense area on T1WI. CONCLUSION: The CP is a highly specific finding for diagnosis of GMPL. If the CP is observed as a hypointense area compared with the cervical stroma on T1WI, GMPL (i.e., LEGH or gastric-type mucinous carcinoma) should be strongly suspected.