Mucosal Side Research Articles

Changes in the Tissue Barrier after Exposure to Lipopolysaccharide on the Apical Side of Enterocytes and the Follicle-Associated Epithelium in Peyer's Patches of the Rat Intestine.

To study the para- and transcellular permeability of columnar epithelium and follicle-associated epithelium of Peyer's patches in the rat intestine, LPS was applied from the mucosal side to simulate the action of endotoxins from gram-negative bacteria of gut microbiota. LPS did not affect transepithelial resistance or sodium fluorescein permeability, but increased the levels of claudin-3 and claudin-4 in enterocytes, suggesting strengthening of the paracellular intestinal barrier. Transcellular permeability was evaluated by electron microscopy based on the number of vesicular structures in the cytoplasm of different cell types. LPS increased the number of small vesicles in follicle-associated epithelium of Peyers' patches. In columnar epithelial cells, LPS reduced the number of smaller vesicles and increased the number of larger ones. LPS did not damage the tissue barrier, but enhanced transcytosis, which could potentiate the effects of endotoxin on its receptors in the intestinal mucosa.

Comparing the Efficacy and Side Effect Profiles of Pazopanib and Sunitinib in the Treatment of Advanced Renal Cell Carcinoma: A Narrative Literature Review

Background: Renal Cell Carcinoma (RCC) is the most common form of kidney cancer, accounting for approximately 85% of all kidney malignancies [1, 3]. Targeted therapies such as Pazopanib and Sunitinib, which inhibit the vascular endothelial growth factor (VEGF) pathway, have become integral to the management of metastatic RCC [4, 5]. Despite their similar mechanisms of action, these agents differ in their side effect profiles, which presents important considerations for patient tolerability and quality of life (QoL) [11, 12]. Objectives: This literature review aims to compare the efficacy and side effect profiles of Pazopanib and Sunitinib in treating advanced or metastatic RCC, providing a synthesis of the current evidence to guide clinicians in optimizing treatment strategies based on patient-specific factors. Methods: A narrative literature review was conducted using a descriptive synthesis approach. Relevant studies from 2006 to 2024 were identified in PubMed, Cochrane Library, and EMBASE. Randomized controlled trials (RCTs) and observational cohort studies were included, with a focus on identifying trends in efficacy and side effect profiles. Conclusion: Pazopanib and Sunitinib provide comparable efficacy in treating advanced RCC, though they differ significantly in their side effect profiles. Pazopanib is generally better tolerated, particularly in reducing fatigue, hand-foot syndrome, and mucosal side effects. In contrast, Sunitinib may be more suitable for patients with concerns about hypertension or hepatotoxicity. Clinicians should carefully balance efficacy with patient-specific tolerability when selecting between these agents. Further research should focus on combination therapies and long-term safety profiles.

Application of Ganoderma lucidum extract for constructing an oral docetaxel delivery system

Docetaxel is one of the most valuable chemotherapeutic drugs, but it has extremely low oral bioavailability. In this study, an oral docetaxel delivery system was constructed based on the extract of Ganoderma lucidum, a well-known medicinal mushroom. First, a G. lucidum extract-docetaxel complex was prepared by stirring and freeze-drying. Results demonstrated that, compared to the docetaxel group, the exposure levels of docetaxel in the complex group were significantly increased in the mouse portal vein (Cmax, 599.7 vs. 58.5 ng/mL; AUC0–12 h, 631.2 vs. 185.9 ng·h/mL), systemic circulation (Cmax, 310.4 vs. 34.9 ng/mL; AUC0–12 h, 467.6 vs. 124.7 ng·h/mL), liver (Cmax, 431.2 vs. 58.4 ng/g liver; AUC0–12 h, 2007.3 vs. 473.0 ng·h/g liver), and lungs (Cmax, 1711.3 vs. 362.7 ng/g lung; AUC0–12 h, 5188.5 vs. 1329.5 ng·h/g lung). Moreover, in the complex group, except for metabolic stability (p > 0.05), transportation from the mucosal side of gut sacs to the serosal side (p < 0.01), solubility (52.6 vs. 4.2 μg/mL), and release of docetaxel in water were significantly improved (15 min, 5.5% vs. 2.3%; 8 h, 35.0% vs. 15.1%). Furthermore, scanning electron microscope (SEM), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD) analysis demonstrated the amorphous existing form of docetaxel. In conclusion, the pharmacokinetics of oral docetaxel in mice was improved by the G. lucidum extract-docetaxel complex, which changed the existing form of docetaxel from crystalline to amorphous. This study provides a simple solution to docetaxel’s low oral bioavailability.

Catharanthus roseus extract attenuates E. coli toxin-induced short circuit current in isolated jejunal epithelium of goat and buffalo

Enterotoxigenic E. coli-derived heat-stable enterotoxin not only alters intestinal barrier functions and produces secretory diarrhea but also causes production losses in livestock. This study aimed to elucidate the ameliorative effect of Catharanthus roseus extract on Cl- secretion in an in vitro model. Isolated jejunal epithelia from goats (N=10) and buffaloes (N=4) were divided into four groups: A) control; B) 1.5% C. roseus extract; C) 10% E. coli toxin, and D) 10% E. coli toxin and 1.5% C. roseus extract. The jejunal epithelia were mounted on Ussing chambers with an exposed surface area of 0.95 cm2 and treated with E. coli toxin on the mucosal side to invoke Cl- channels. Transepithelial potential difference (Pdt), tissue conductance (Gt), and short circuit current (Isc) were determined under voltage-clamped conditions. E. coli toxin produced a significant increase in the Pdt, Gt, and Isc for both goat and buffalo jejunal epithelia, whereas C. roseus extract on the mucosal side alone or followed by the E. coli toxin decreased these parameters, which were comparable with the control. The change in Isc was more pronounced in goats than buffaloes (ΔIscgoat &gt; ΔIscbuff). In experiments with the goat jejunal epithelia, replacement of Cl- from the mucosal buffer decreased Isc, similar to a decrease observed for the C. roseus extract groups. In conclusion, the results of this study suggest that C. roseus extract has a potential to attenuate E. coli-induced Cl- secretion in isolated jejunal epithelia of goats and buffaloes.&#x0D; Keywords: Catharanthus roseus extract; Electrophysiology; Secretory diarrhea; Small intestine, Ruminants

AMPK protects endothelial cells against HSV-1 replication via inhibition of mTORC1 and ACC1.

Herpes simplex virus type 1 (HSV-1) is a widespread contagious pathogen, mostly causing mild symptoms on the mucosal entry side. However, systemic distribution, in particular upon reactivation of the virus in immunocompromised patients, may trigger an innate immune response and induce damage of organs. In these conditions, HSV-1 may infect vascular endothelial cells, but little is known about the regulation of HSV-1 replication and possible defense mechanisms in these cells. The current study addresses the question of whether the host cell protein AMP-activated protein kinase (AMPK), an important metabolic sensor, can control HSV-1 replication in endothelial cells. We show that downregulation of the catalytic subunits AMPKα1 and/or AMPKα2 increased HSV-1 replication as monitored by TCID50 titrations, while a potent AMPK agonist, MK-8722, strongly inhibited it. MK-8722 induced a persistent phosphorylation of the AMPK downstream targets acetyl-CoA carboxylase (ACC) and the rapamycin-sensitive adaptor protein of mTOR (Raptor) and, related to this, impairment of ACC1-mediated lipid synthesis and the mechanistic target of the rapamycin complex-1 (mTORC1) pathway. Since blockade of mTOR by Torin-2 as well as downregulation of ACC1 by siRNA also decreased HSV-1 replication, MK-8722 is likely to exert its anti-viral effect via mTORC1 and ACC1 inhibition. Importantly, MK-8722 was able to reduce virus replication even when added after HSV-1. Together, our data highlight the importance of endothelial cells as host cells for HSV-1 replication upon systemic infection and identify AMPK, a metabolic host cell protein, as a potential target for antiviral strategies against HSV-1 infection and its severe consequences. IMPORTANCE Herpes simplex virus type 1 (HSV-1) is a common pathogen that causes blisters or cold sores in humans. It remains latent in infected individuals and can be reactivated multiple times. In adverse conditions, for instance, in immunocompromised patients, HSV-1 can lead to serious complications such as encephalitis, meningitis, or blindness. In these situations, infection of endothelial cells lining the surface of blood vessels may contribute to the manifestation of disease. Here, we describe the role of AMP-activated protein kinase (AMPK), a potent regulator of cellular energy metabolism, in HSV-1 replication in endothelial cells. While downregulation of AMPK potentiates HSV-1 replication, pharmacological AMPK activation inhibits it by limiting the availability of required host cell macromolecules such as proteins or fatty acids. These data highlight the role of metabolic host cell proteins as antiviral targets and reveal activation of endothelial AMPK as a potential strategy to protect from severe consequences of HSV-1 infection.

Lateral Osteotomy for the Surgical Treatment of the Asian Wide Nose.

Narrowing of the nasal dorsum allows for a more pleasing moderate width. We here introduce a lateral osteotomy technique that is less traumatic and easier to perform than commonly used procedures in Asian and share our experiences in the application. After a blunt dissection of the periosteum at the mucosal side of the nasal bone, all patients who underwent treatment using nasal osteotomy at the level of the maxillary nasal process were retrospectively analyzed. The bony nasal width, height, and the nasal lateral wall slope of bone before and after surgery were measured. The postoperative outcomes, complications, and patient satisfaction were analyzed and evaluated. From January 2008 to January 2018, nasal dorsum narrowing was implemented in 106 patients. On average, nasal width was significantly decreased and no change in nose height after the nasal osteotomy. The nasal width was significantly reduced by 8.51 ± 2.16 mm compared with before surgery. The slope of the nasal lateral wall was reduced from the mean of 155.0 ± 7.63-degree preoperation to the mean of 135.25 ± 7.50-degree postoperation. The follow-up period ranged from 6 months to 4 years, with an average of 10.3 months. This type of nasal bone base osteotomy is a simple and feasible method for the treatment of wide Asian noses with a high patient acceptance and stable postoperative results. Level IV.

Metabolism and Microstructure of the Small Intestine Wall in Patients With Colorectal Cancer

RELEVANCE In patients with colorectal cancer (CRC), the normal small intestine, located outside the pathological focus, undergoes changes that may be the cause of digestive dysfunction after radical surgery to remove the tumor.The assessment of metabolic and microstructural changes in the ileum mucosa in patients with colorectal cancer is necessary to correct the algorithms of postoperative therapy and enteral nutrition. Modern means of optical bioimaging are potentially capable of solving this complex diagnostic problem.AIM OF STUDY To study the features of metabolism and morphological structure of the wall of a conditionally normal small intestine in the mucosa in patients with stage 1–3 CRC using macro- FLIM and optical coherence tomography (OCT).MATERIAL AND METHODS The object of the study was the wall of the ileum (66 samples) from the mucosal side of patients with histologically confirmed CRC stages 1–3 with tumor location in the right sections of the colon. Eight samples were obtained from patients with stage 1 CRC, 38 samples were obtained from patients with stage 2 and 20 samples were obtained from patients with stage 3 tumor. The volume of surgical intervention is right-sided hemicolectomy with total mesocolonectomy, CME (D2 lymph node dissection). Fresh tissue samples were examined using fluorescent lifetime macroimaging (macro-FLIM ) and OCT, followed by histological analysis of the material.RESULTS According to a histological study in the small intestine of patients with stage 1 CRC, the mucosa is covered with a normal single-layer prismatic border epithelium. In the intestine samples of patients with stage 2 CRC, mucus hypersecretion with areas of fibrosis and vascular congestion was observed. At the 3rd stage of CRC, the mucous membrane of the small intestine was loose, with local thickenings, areas of fibrosis with severe leukostasis, and foci of atrophy. None of the samples showed histological signs of a malignant tumor.According to OCT data, in the mucous membrane of the small intestine in patients with the 1st and 2nd stages of CRC, the contours of the villi and, partially, the crypts were well visualized. The structure of the villi was smooth, not coarse, and the shape was regular. In patients with stage 3 CRC, the contours of the crypts and villi were indistinct. There were no differences in the OCT picture between histologic preparations in the 1st and 2nd stages of CRC: the structure of the villi of the small intestine was clear, the shape was unchanged. According to FLIM data, statistically significant differences were revealed in the mean fluorescence lifetime values of reduced nicotinamide dinucleotide (phosphate) NAD(P)H (τm) between 2nd and 3rd (p=0.031), 1st and 3rd (p=0.018) by CRC stages. At the 1st stage of CRC τm was 1.61 [1.30; 2.02] ns, at the 2nd stage 1.50 [1.36; 1.73] ns, at the 3rd stage 1.37 [1.22; 1.51] ns. The FLIM results suggest an increase in the role of glycolysis in enterocyte energy metabolism along with progression of the CRC stage.CONCLUSION In patients with cancer of the right colon, lesions of the microstructure of the mucous membrane were revealed in the ileum not affected by the malignancy. At the same time, the severity of microstructural disorders in the wall of the small intestine is associated with the stage of tumor development in the colon. Bioimaging technologies, namely, methods of optical coherence tomography and fluorescence lifetime macroimaging, made it possible to objectively display microstructural and metabolic disorders in the ileum wall. The data of optical colorectal tomography demonstrated differences in the structural picture of the intestinal villi in patients with stages 1–2 and 3 of colorectal cancer. Results of fluorescence lifetime macroimaging of the metabolic cofactor nicotinamide dinucleotide (phosphate) confirmed an increase in the role of glycolysis in the energy metabolism of enterocytes along with an increase in the stage of colorectal cancer. The identified disorders in the state of the small intestine develop in patients with colorectal cancer before surgery and are highly likely to be an important pathogenetic link of malabsorption in the postoperative period. If the hypothesis is confirmed, the developed algorithm for the complex diagnosis of microstructural and metabolic disorders in tissues will expand the possibilities for the rehabilitation of patients with cancer of the right colon.

Investigation of the efficacy of systemic N-Acetyl Cysteine therapy preventing nasal mucositis following radiotherapy.

Radiotherapy (RT) is one of the main methods used in the treatment of head and neck cancers but may cause mucosal side effects in the tumor area and surrounding structures. These include nasal mucosal disorders and chronic rhinosinusitis due to disruption of the mucociliary system. This situation seriously affects the quality of life of the patients and there is no accepted effective method for its treatment yet. In our study, we aimed to examine the side effects of RT on the nasal mucosa and mucociliary system and to investigate histopathologically and immunohistochemically the effectiveness of N-acetyl cysteine (NAC) in preventing these side effects of RT. The study was carried out with 30 female Sprague Dawley rats devided in three groups. No intervention was made in the control group. On the second day of the experiment, 30 Gy radiotherapy was applied to the head area in the RT group. NAC was administered intraperitoneally at a dose of 1 g/kg/day for 14 days from the first day of the study to the RT+ NAC group. On the second day, 30 Gy of radiotherapy was applied to the head area 1 hour after the NAC application. On the 14th day, 1 hour after NAC was applied to the RT+NAC group, all animals were sacrificed. The nasal mucosa samples were stained with hematoxylin-eosin, and the intensity and extent of staining sentan in the nasopharyngeal tissue samples were evaluated by immunohistochemical staining using anti-SNTN antibody. The loss of cilia in the nasal tissue was lower in the RT+NAC group than in the RT group. The intensity and extent of staining in the nasopharyngeal tissue of Sentan was higher in the RT+NAC group than in the RT group. Mucosal neutrophil and mononuclear inflammatory cell infiltration in the nasal tissue, vascular dilatation, hyperemia and hemorrhage, erosion and shedding of the mucosal epithelium, mucosal ulceration were found to be similar in the RT+NAC group and the control group. It was milder in the RT+NAC group than in the RT group, but not statistically significant. Radiotherapy caused pathological changes in the nasal mucosa, caused loss of cilia and a decrease in the level of Sentan, the cilia apical protein. The results of our study showed that NAC treatment can reduce the side effects of RT on the nasal mucosa. It also showed that NAC was effective in preventing the loss of cilia, which is the building block of the mucociliary system, and improving the expression of Sentan.

Assessment and comparison of microcirculation and macrocirculation in horses undergoing emergency exploratory celiotomy versus elective surgical procedures.

To assess oral buccal microcirculation by hand-held videomicroscopy in horses during colic surgery, comparing microcirculation values with macrocirculatory parameters and with those of healthy elective surgical horses. Clinical prospective study. Client-owned horses (nine in the colic group; 11 in the elective group). In the colic group, buccal mucosal side stream dark-field microscopy (DFM) videos, cardiac output (CO), mean arterial pressure (MAP), and lactate were obtained at three timepoints under general anesthesia (30, 90, and 150 min after induction). Video analysis was used to determine total vessel density, proportion of perfused vessels, perfused vessel density, and heterogeneity index. Dark-field microscopy videos, MAP, and lactate were obtained at a single timepoint under general anesthesia (45 min after induction) in the elective group. There were no differences in microcirculatory parameters between colic and elective horses, nor was there a difference across timepoints in the colic group. There was a weak negative correlation between microvascular parameters and CO (rho = -0.23). The colic group did not have decreased microcirculation in comparison with the healthy elective group. Dark-field microscopy did not correlate well with macrocirculatory parameters in the colic group. Dark-field microscopy may not be a sensitive enough indicator to detect differences in microcirculation between colic and elective groups. The lack of difference in microcirculation may be due to sample size, probe location, or variation in disease severity.

Effect of sodium concentration and mucosal pH on apical uptake of acetate and butyrate, and barrier function of the isolated bovine ruminal epithelium

This study was conducted to investigate the role of Na+ on ruminal short-chain fatty acid (SCFA) absorption and barrier function when isolated ruminal epithelium was exposed to high and low pH ex vivo. Nine Holstein steer calves (322 ± 50.9 kg of BW) consuming 7.05 ± 1.5 kg DM of a TMR were euthanized and ruminal tissue was collected from the caudal-dorsal blind sac. Tissues were mounted between 2 halves of Ussing chambers (3.14 cm2) and exposed to buffers that contained low (10 mM) or high (140 mM) Na+ with low (6.2) or high (7.4) mucosal pH. The same buffer solutions were used on the serosal side except that pH was maintained at 7.4. Buffers used to evaluate SCFA uptake contained bicarbonate to determine total uptake or excluded bicarbonate and included nitrate to determine non-inhibitable uptake. Bicarbonate-dependent uptake was calculated as the difference between the total and non-inhibitable uptake. Acetate (25 mM) and butyrate (25 mM) were spiked with 2-3H-acetate and 1-14C-butyrate, respectively, and were then added to the mucosal side, incubated for 1 min, and tissues were analyzed to evaluate rates of SCFA uptake. Tissue conductance (Gt) and the mucosal-to-serosal flux of 1-3H-mannitol were used to assess barrier function. There were no Na+ × pH interactions for butyrate or acetate uptake. Decreasing mucosal pH from 7.4 to 6.2 increased total acetate and butyrate uptake, and bicarbonate-dependent acetate uptake. Flux of 1-3H-mannitol was not affected by treatment. However, high Na+ concentration reduced Gt and prevented an increase in Gt from flux period 1 to flux period 2. The results of this study indicate that although providing more Na+ to the ruminal epithelium does not affect SCFA uptake or mannitol flux, it may help stabilize tissue integrity.

Lower Lip Reconstruction Using a Sensory Anterolateral Thigh Flap as the First Choice

Summary: Local flaps from the upper lip and cheeks have been the first choice for two-thirds to total resection of the lower lip. However, these local flap techniques involve many clinical problems, including small a mouth, drooling, scarring, and hypesthesia. The improvement of free anterolateral thigh (ALT) flap transfer can solve these problems with expansion of the application of free flaps for lower lip reconstruction. The patient in this case was a 56-year-old man with squamous cell carcinoma of the lower lip (cT3N1M0). Subtotal lower lip resection preserving both corners of the mouth with bilateral neck dissection was performed. Simultaneously, a sensory ALT flap was elevated with an 8 × 6 cm skin island and a lateral femoral cutaneous nerve. The lateral and medial sides of the fascia lata were processed into 1-cm-wide strings, which were tunneled through the orbicularis oris muscle of the upper lip and sutured to the orbicularis oris muscle at the mucosal side of the philtrum. The lateral femoral cutaneous nerve and right mental nerve were sutured. At 3 months, a second surgery was performed to replace the ALT flap on the white labial side with a clavicle full-thickness skin graft. This surgery achieved four important factors: opening and closing of the mouth, sensory function of the lower lip, cosmetic appearance, and minimization of donor-site damage. We believe the worldwide improvement of microsurgery techniques enables lower lip reconstruction using the sensory ALT flap to be selected as the first choice for two-thirds to total lower lip defects.

V08-09 TRANSURETHRAL DORSAL BUCCAL GRAFT URETHROPLASTY FOR PROXIMAL FEMALE URETHRAL STRICTURES

You have accessJournal of UrologyCME1 Apr 2023V08-09 TRANSURETHRAL DORSAL BUCCAL GRAFT URETHROPLASTY FOR PROXIMAL FEMALE URETHRAL STRICTURES Francis Jefferson, Jonathan Warner, Maraika Robinson, and Brian Linder Francis JeffersonFrancis Jefferson More articles by this author , Jonathan WarnerJonathan Warner More articles by this author , Maraika RobinsonMaraika Robinson More articles by this author , and Brian LinderBrian Linder More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003306.09AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Treatment options for proximal female urethral strictures have significant limitations such as high recurrence rate (urethral dilation) and de novo stress urinary incontinence (flap/graft reconstruction). The objective of this video was to describe a novel dorsal inlay buccal graft urethroplasty technique that reduces technical difficulty and eliminates the need for urethral mobilization. METHODS: Stay sutures are placed at the urethral meatus, and a nasal speculum is placed into the urethra staying distal to the stricture. A beaver blade is then used to incise the urethra at the 12 o'clock, 10 o’clock, and 2 o’clock positions; these are superficial, non-full thickness incisions. A laparoscopic suture passing device is then used to pass a suture from the bladder to the urethral lumen at the 12:00 o'clock position. The suture is then passed through corresponding mid portion of the buccal graft ensuring that the mucosal side will be in the urethral lumen when the graft is deployed. This is repeated at the 10 o'clock and 2 o'clock positions with placement of the proximal suture at the level of the bladder neck and then through the corresponding location on the buccal graft. The graft is then parachuted into position at the level of the bladder neck. A laparoscopic knot pusher is then used to tie down the proximal sutures through the urethra. After trimming the excess buccal graft flush with the meatus, the distal aspect of the graft is sutured to the vaginal epithelium to recreate the urethral meatus. A wide-bore catheter is placed for 3 weeks postoperatively. RESULTS: In 6 consecutive patients treated with this technique with a median follow-up of 3.9 months, surgical success has been 100% as indicated by urethral patency on cystourethroscopy and subjective symptom improvement. There have been no cases of de novo stress urinary incontinence. Pre- and post-operative maximum urine flow rate (Qmax) and post-void residual volumes (PVR) are shown in the table. CONCLUSIONS: A transurethral inlay approach for dorsal buccal graft placement is a feasible option for management of female proximal urethral structure. Given decreased periurethral dissection compared to other techniques, this approach may decrease the risk of de novo stress urinary incontinence. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e751 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Francis Jefferson More articles by this author Jonathan Warner More articles by this author Maraika Robinson More articles by this author Brian Linder More articles by this author Expand All Advertisement PDF downloadLoading ...

Naringenin alters the pharmacokinetics of ranolazine in part through the inhibition of cytochrome P450 (3A4) and P-glycoprotein

BackgroundThis study set out to look at how naringenin affected the pharmacokinetics of ranolazine in rats. The pharmacokinetic investigation of ranolazine in rats following oral administration of ranolazine with or without coadministration of naringenin was successfully conducted using the established technique. Animals were administered the same medications for 7 days as part of a multiple dosage study (MDS), and the amount of ranolazine in plasma was calculated on 18 days. The intestinal transit of ranolazine in the presence and absence of naringenin and verapamil was examined in an in vitro experiment using the intestinal sacs of rats and chickens (P-glycoprotein inhibitor).ResultsNaringenin raised the maximal level (Cmax) of ranolazine from 231 ± 10.16 to 303.67 ± 9.46 and 325.67 ± 21.81 ng/mL in SDS and MDS, respectively. Moreover, naringenin elevated the area under the curve (AUC) of ranolazine from 1293.54 ± 37.18 to 1505.38 ± 100.30 and 1575.42 ± 76.98 ng/mL/h in SDS and MDS. In the presence of naringenin, there was an increase in the transfer of ranolazine from the mucosal side to the serosal side. Naringenin inhibits the enzymes Cytochrome P450 (3A4) or (CYP3A4) and P-glycoprotein (P-gp). The findings showed that naringenin might have a considerable impact on ranolazine pharmacokinetics, including extending its t1/2 and raising its AUC.ConclusionsThe findings of the study showed that naringenin inhibits the enzymes CYP3A4 and P-gp. Therefore, naringenin might have a considerable impact on ranolazine pharmacokinetics, including extending its t1/2 and raising its AUC.Graphical abstract

Evaluation of chronic cigarette smoke exposure in human bronchial epithelial cultures.

Cigarette smoke (CS) exposure induces both cytotoxicity and inflammation, and often causes COPD, a growing cause of morbidity and mortality. CS also inhibits the CFTR Cl- channel, leading to airway surface liquid dehydration, which is predicated to impair clearance of inhaled pathogens and toxicants. Numerous in vitro studies have been performed that utilize acute (≤24 h) CS exposures. However, CS exposure is typically chronic. We evaluated the feasibility of using British-American Tobacco (BAT)-designed CS exposure chambers for chronically exposing human bronchial epithelial cultures (HBECs) to CS. HBECs are polarized and contain mucosal and serosal sides. In vivo, inhaled CS interacts with mucosal membranes, and BAT chambers are designed to direct CS to HBEC mucosal surfaces while keeping CS away from serosal surfaces via a perfusion system. We found that serosal perfusion was absolutely required to maintain HBEC viability over time following chronic CS exposure. Indeed, with this system, we found that CS increased inflammation and mucin levels, while decreasing CFTR function. Without this serosal perfusion, CS was extremely toxic within 24 h. We therefore propose that 5- and 10-day CS exposures with serosal perfusion are suitable for measuring chronic CS exposure and can be used for monitoring new and emerging tobacco products.

Reduced sodium absorption in the colon under serotonin is a potential factor aggravating secretory diarrhea.

Serotonin is a substance with a propulsive effect on the gastrointestinal tract. It stimulates the intestinal secretion of water and electrolytes, and plays an important role in the pathophysiology of secretory diarrhea. However, the influence of serotonin on intestinal absorption is very poorly understood. This study aimed to evaluate the serotonin and selected antagonists of serotonin receptors, i.e., ondansetron (5-HT3) and GR113808 (5-HT4), on electrogenic sodium ion absorption in the colon. The electrophysiologic method developed by Ussing and modified with a stimulating function on the mucosal side of the isolated colon wall was used. The influence of selected serotonergic compounds on the electrogenic transport of sodium ions under stationary conditions and mechanical stimulation was investigated. For this purpose, experiments were performed on specimens of isolated rabbit colon. Amiloride and bumetanide were used as reagents directly controlling individual ion transport. The data were analyzed using tests for paired samples (paired sample t-test, Wilcoxon signed-rank test and one-sided sign test). Serotonin reduced stationary and stimulated colonic sodium absorption. The 5-HT3 receptor antagonist did not influence the studied phenomenon, while 5-HT4 antagonists acted contrary to serotonin. Serotonin reduces both stationary and stimulated sodium ion absorption, thus playing an important role in the pathophysiology of secretory diarrhea. The described phenomenon depends on serotonin's action on 5-HT4 receptors.

Securing Resection Margin Using Indocyanine Green Diffusion Range on Gastric Wall during NIR Fluorescence-Guided Surgery in Early Gastric Cancer Patients.

Near-infrared (NIR) fluorescence lymphography-guided minimally invasive gastrectomy using indocyanine green (ICG) is employed to visualize draining lymphatic vessels and lymph nodes. Endoscopically injected ICG spreads along the gastric wall and emits fluorescence from the serosal surface of the stomach. We aimed to assess the efficacy of ICG diffusion in securing the resection margin. We retrospectively analyzed 503 patients with early gastric cancer located in the body of the stomach who underwent fluorescence lymphography-guided gastrectomy from 2018 to 2021. One day before surgery, ICG was endoscopically injected into four points of the submucosal layer peritumorally. We measured the extent of resection and the resection line based on the ICG diffusion area from the specimen using NIR imaging. The mean area of the ICG diffusion was 82.7 × 75.3 and 86.7 × 80.2 mm2 on the mucosal and serosal sides, respectively. After subtotal gastrectomy, the length of the proximal resection margin was 38.1 ± 20.1, 33.4 ± 22.2, and 28.7 ± 17.2 mm in gastroduodenostomy, loop gastrojejunostomy, and Roux-en-Y gastrojejunostomy, respectively. The ICG diffusion area along the gastric wall secured a resection margin of &gt;28 mm. The ICG diffusion range can be used as a simple and easy method for determining the resection margin during gastrectomy using NIR imaging.

The "Kite-t-FAMMIF": A Novel Technique for Reconstruction of Extensive Soft Palate Resection.

Summary:Total soft palate reconstruction is a challenge for the head and neck surgeon. Velopharyngeal incompetence resulting from soft palate resection impairs both speech and swallowing and significantly affects the quality of life of the patients. Radial forearm free flap is the reconstructive technique most used worldwide, but it requires microsurgical skills, is associated with high donor site morbidity, and shrinks during the healing process, especially after adjuvant radiotherapy. We present a novel technique using a single “kite-shaped” tunnelized-facial artery myomucosal island flap (t-FAMMIF) and report very favorable functional outcomes. Three patients in whom a kite-shaped flap was used to reconstruct a total soft palate defect after squamous cell carcinoma resection were included. In two of them, the resection included both tonsils due to cancer spreading to the tonsillar fossae. The mucosal and muscular sides of a single t-FAMMIF flap were able to restore the oral and nasal lining of the palate, respectively, without the need to fold the flap. All patients were able to tolerate an oral soft diet 10 days after surgery. No complications were detected. A complete mucosalization on the nasal lining was observed by video-endoscopy 3 weeks after surgery. No case of shrinking of the flap was observed during the follow-up, and speech and swallowing functions were not impaired after complete wound healing. Kite-shaped t-FAMMIF represents an excellent and feasible reconstructive option for extensive postablative soft palate defects.

S1163 Endoscopic Full Thickness Resection of Gastrointestinal Neoplasia – Single Center Experience

Introduction: Endoscopic full-thickness resection (EFTR) is emerging therapeutic option for en-bloc treatment of subepithelial tumors and epithelial neoplasia with significant fibrosis. Study aim was to evaluate results at advanced endoscopy center. Methods: This was retrospective analysis of 18 EFTR cases from 01/2020 till 11/2021, that were performed in advanced endoscopy center with a dedicated full thickness resection device (FTRD®, Ovesco, Germany). We recorded the demographic, procedural and technical characteristics. Lesion pathology (surface size, type, location), timing of procedure, technical success (defined as reaching the lesion, deploying the clip, and performing an en bloc and macroscopically complete resection), clinical success (defined as R0 resection and histopathology evaluation compatible with adequate endoscopic treatment) and rate of procedure-related complications (bleeding, perforation, need for emergency surgery, infectious complications and cardio-pulmonary adverse events associated with sedation) were also recorded (Table). Results: Majority of lesions had previous failed attempts at removal (n=10, 55.5%). Other lesions (n=8, 44.4%) included appendiceal orifice (n=6, 33.3%) or neuroendocrine neoplasia (n=2, 11.1%). Mean age of patients was 67.4 years +/- (SD) 10.9 years. 8/18 (44.4%) patients were female. Procedures were performed with conscious sedation (midazolam) and analgesia (piritramide), with pulse oximetry monitoring. There were no cardiopulmonary adverse events. (Figure) One procedure was aborted due to postsurgical anatomy; the endoscope with the FTRD device could not be passed through. One patient developed post procedural appendicitis and a surgical appendectomy was performed, although the EFTR was technically successful. No other complications were recorded. Mean procedure time was 42.1 +/- (SD) 14.3 minutes. Technical success of the procedure was 94.4% (n=17/18), clinical success was achieved in 88.2% (n=15/17). One patient was referred to surgery due to insufficient safety margins of removed specimen and one patient due to presence of invasive adenocarcinoma (pT2). All but one (post-procedural appendicitis) patients were discharged after one day of observation. Conclusion: Our results confirm that EFTR is effective endoscopic technique. It is exceptionally useful in fibrotic lesions and neuroendocrine neoplasia. Technically less challenging than endoscopic submucosal dissection it can still pose technical difficulties especially in cases with postsurgical anatomy.Figure 1.: A) Pre-EFTR marks of a 20 mm sessile serrated lesion of the appendiceal orifice. B) Deployment of the EFTR device. C) Resection defect after EFTR. D) Mucosal side of the resected specimen. The pathology showed sessile serrated lesion. Table 1. - Demographics and Procedure Characteristics. SD - standard deviation. Timing of procedure (time of endoscopy and deployment of the device). Technical success (defined as reaching the lesion, deploying the clip, and performing an en bloc and macroscopically complete resection). Clinical success (defined as R0 resection and histopathology evaluation compatible with adequate endoscopic treatment). Other – hyperplastic polyps, fibrotic tissue and lipoma Sex (n=18) (n, %) Male 10 (55.6) Female 8 (44.4) Mean age +/- SD (years) 67.4 +/- 10.9 ASA classification, (n, %) II 12 (66.7) III 6 (33.3) Mean dose of midazolam +/- SD, mg 0.7 +/- 0.83 Mean dose of piritramide +/- SD, mg 4.5 +/- 5.1 Location of the lesion, n=18 (n, %) Rectum 8 (44.4) Transverse Colon 2 (11.1) Ascending Colon 1 (5.6) Appendiceal Orifice 6 (33.3) Body of Stomach 1 (5.6) Mean Procedure Time +/- SD, min 42.1 +/- 14.3 Technical success, n=18 (n, %) Yes 17 (94.4) No 1 (0.06) Clinical success, n=17 (n, %) Yes 15 (88.2) No 2 (12.8) Pathohistology of the Retrieved Specimen, n=17 (n, %) Adenoma with Low Grade Dysplasia 5 (29.4) Sessile Serrated Lesion 3 (17.6) Adenocarcinoma 3 (17.6) Neuroendocrine Neoplasia 2 (11.8) Other 4 (23.5)

SARS-CoV-2 causes secretory diarrhea with an enterotoxin-like mechanism, which is reduced by diosmectite

Background and aimsThe pathophysiology of SARS-CoV-2-associated diarrhea is unknown. Using an experimental model validated for rotavirus-induced diarrhea, we investigated the effects of SARS-CoV-2 on transepithelial ion fluxes and epithelial integrity of human intestinal cells. The effect of the antidiarrheal agent diosmectite on secretion was also evaluated following its inclusion in COVID-19 management protocols. MethodsWe evaluated electrical parameters (intensity of short-circuit current [Isc] and transepithelial electrical resistance [TEER]) in polarized Caco-2 cells and in colonic specimens mounted in Ussing chambers after exposure to heat-inactivated (hi) SARS-CoV-2 and spike protein. Spectrofluorometry was used to measure reactive oxygen species (ROS), a marker of oxidative stress. Experiments were repeated after pretreatment with diosmectite, an antidiarrheal drug used in COVID-19 patients. ResultshiSARS-CoV-2 induced an increase in Isc when added to the mucosal (but not serosal) side of Caco-2 cells. The effect was inhibited in the absence of chloride and calcium and by the mucosal addition of the Ca2+-activated Cl– channel inhibitor A01, suggesting calcium-dependent chloride secretion. Spike protein had a lower, but similar, effect on Isc. The findings were consistent when repeated in human colonic mucosa specimens. Neither hiSARS-CoV-2 nor spike protein affected TEER, indicating epithelial integrity; both increased ROS production. Pretreatment with diosmectite inhibited the secretory effect and significantly reduced ROS of both hiSARS-CoV-2 and spike protein. ConclusionsSARS-CoV-2 induces calcium-dependent chloride secretion and oxidative stress without damaging intestinal epithelial structure. The effects are largely induced by the spike protein and are significantly reduced by diosmectite. SARS-CoV-2 should be added to the list of human enteric pathogens.

Sphingomyelin localization in the intestinal crypt surface

Macroscopic lipid observation in the organs of living small animals has not been realized. Here, we visualized sphingomyelin (SM) in the intestines of living mice using an SM-binding protein (EqtII-EGFP-His) under two-photon microscopy. The SM was identified as 10 μm spots in glands of the lamina propria of the mucosa in the large and small intestines. The spots vertically penetrated from the serosa toward the mucosal side. At the edge of the mucosal side in the small intestine, these spots connected with each other and formed horizontal lines. For the large intestine, the horizontal lines became a surface, indicating that SM covered the whole crypt membrane. Detailed observation revealed thin SM-positive lines that connected the spots and the blood vessels in the small intestine. Thus, SM exists at crypt surfaces and inside crypts of the intestines and can regulate the functions of the digestion system.