Mucosal Border Research Articles

Comparison of narrow band and fluorescence molecular imaging to improve intraoperative tumour margin assessment in oral cancer surgery

ObjectiveNew techniques have emerged to aid in preventing inadequate margins in oral squamous cell carcinoma (OSCC) surgery, but studies comparing different techniques are lacking. Here, we compared narrow band imaging (NBI) with fluorescence molecular imaging (FMI), to study which intraoperative technique best assesses the mucosal tumour margins. Materials and MethodsNBI was performed in vivo and borders were marked with three sutures. For FMI, patients received 75 mg of unlabelled cetuximab followed by 15 mg cetuximab-800CW intravenously-two days prior to surgery. The FMI borders were defined on the excised specimen. The NBI borders were correlated with the FMI outline and histopathology. ResultsSixteen patients were included, resulting in 31 NBI and 30 FMI measurements. The mucosal border was delineated within 1 mm of the tumour border in 4/31 (13 %) of NBI and in 16/30 (53 %) FMI cases (p = 0.0008), and within 5 mm in 23/31 (74 %) of NBI and in 29/30 (97 %) of FMI cases (p = 0.0048). The median distance between the tumour border and the imaging border was significantly greater for NBI (3.2 mm, range −6.1 to 12.8 mm) than for FMI (0.9 mm, range −3.0 to 7.4 mm; p = 0.028). Submucosal extension and previous irradiation reduced NBI accuracy. ConclusionEx vivo FMI performed more accurately than in vivo NBI in mucosal margin assessment, mainly because NBI cannot detect submucosal extension. NBI adequately identified the mucosal margin especially in early-stage and not previously irradiated tumours, and may therefore be preferable in these tumours for practical and cost-related reasons.

Measurement of tracheal diameters using ultrasonography versus computed tomography in Beagle dogs

ObjectiveTo compare ultrasonography with computed tomography (CT) for assessment of tracheal diameter as a feasibility study for endotracheal tube selection. Study designProspective study. AnimalsA total of nine Beagle dogs with a median (interquartile range) weight of 7.4 (7.2–7.7) kg. MethodsTracheal diameter measurements were obtained at two locations: 1 cm proximal to caudal border of the cricoid cartilage (sublaryngeal; SL) and dorsal to above cranial border of the manubrium (thoracic inlet; TI). For CT, dogs were anesthetized with propofol and sevoflurane, in sternal recumbency, and measurements obtained after controlled ventilation–induced apnea and the endotracheal tube cuff was deflated. Transverse diameter, right and left 45° oblique diameters were measured. For ultrasonography, unsedated dogs were standing with slight neck extension, and images obtained in ventrodorsal, 45° right and left oblique ways after expiration. Diameters between the tracheal lumen mucosal borders were measured. The degree of agreement between the tracheal diameters measured at SL and TI locations with CT (TDCT-SL and TDCT-TI) and ultrasonography (TDUS-SL and TDUS-TI) was verified using the Bland-Altman method. ResultsThe agreement between the measurements obtained with CT and ultrasonography was revealed by Bland-Altman analyses, although ultrasonography tended to slightly underestimate the tracheal diameter. Conclusions and clinical relevanceUltrasonography can be applied for tracheal diameter measurement. Although further studies are required, an endotracheal tube selection method, using ultrasonography, could be proposed.

A diminutive polyp with synchronous liver metastasis: Luck or skill?

A 59-year-old Caucasian man was admitted in our hospital for abdominal pain and weight loss. Abdominal ultrasound revealed hepatic lesions suggestive for metastasis. Therefore, Endoscopy was performed to find the primary neoplasia. Esophagogastroduodenoscopy was normal. Two polyps were detected on colonoscopy: a sub-centimetric pedunculated one (tubular adenoma) and a 5 mm sessile one, both at the sigmoid colon. The latter appeared ulcerated at the top with regular round pit (KUDO I-II) and mucosal borders, highlighted by NBI (Fig.

A Qualitative Comparison of Manual and K‐means Segmentation for Whole‐slide Histology Images of Rabbit Vocal Folds

IntroductionSurgical treatment for subglottic stenosis often faces recurrence of narrowing and patients continue to face quality of life issues. Currently, biomechanical models that inform surgical treatments are difficult to create due to vocal fold intricacies and trouble distinguishing between tissue types–muscle, mucosa, and cartilage. Improved models of laryngeal microanatomy can be used to assess and predict surgical outcomes for patients who suffer from subglottic stenosis. While manual segmentation of histology is the standard, automatic segmentation can be more efficient, sensitive, and specific in tissue differentiation. Manual segmentation faces challenges like extensive operator time and inter‐rater subjectivity. The aim of this study, therefore, was to qualitatively compare manual segmentation to automatic k‐means segmentation of whole‐slide histology rabbit vocal fold images. This is the preliminary step towards enhancing segmentation and, later, achieving a high‐fidelity human larynx model.Methods134 whole‐slide histology images were manually segmented from seven rabbits using colored masks for muscle, cartilage, mucosa, and adipose tissue. Of those images, 31 were also selected for segmentation using k‐means for initial qualitative comparison. At least two images were segmented per rabbit. K‐means segmentation is optimal for our multidimensional data. Since it is deterministic, we selected the number of clusters as our parameter. After inspecting n=1‐10 clusters, n=4 was chosen as qualitatively producing the most distinct clusters without oversampling.ResultsFor our preliminary results, we compared the histological image, the manual segmentation, and the automatically segmented image. In the automatic segmentations, tissue type is distinguished by the grayscale contrast. The four classes visible are cartilage, muscle, adipose tissue, and mucosa. There is occasional loss of visualization of adipose tissue and mucosa, however, the cartilage and muscle tissues remain distinct. The mucosal area boundaries remain clear despite some visualization loss within the mucosal borders, therefore, mucosa can be distinguished from adjacent cartilage and muscle. Training on a large dataset like other machine learning algorithms is unnecessary for k‐means, which is ideal for our relatively small sample size. The speed and versatility of k‐means has qualitatively demonstrated comparable results to our manual segmentations.ConclusionFuture directions for our project include conducting k‐means segmentation of the remainder of the 134 images collected. We have also tested mean‐shift clustering and a deep learning convolutional neural network (CNN) to compare automatic segmentation methods to one another, and to the standard manual segmentation/ground truth. Future testing also includes quantitative analysis of these algorithms’ accuracy. Beyond our histology images, we have at least 14 MR images (at least two per rabbit) of the larynges as well. We intend to combine and overlay the structural detail of the histology images with the soft tissue differentiation of the MRI.

Linked color imaging effectively detects the endoscopic atrophic border in transnasal endoscopy.

In oral endoscopy, linked color imaging (LCI) detects atrophic border and gastric mucosal diseases better than white light imaging (WLI), but its usefulness in transnasal endoscopy has not been fully investigated. Here, we retrospectively compared WLI and LCI using the L*a*b* color space in images from 57 patients aged ≥20 years who had undergone transnasal endoscopy as part of a health check-up from May 2016 to January 2017. We measured color differences at the atrophic/non-atrophic and fundic/pyloric mucosal borders. Gastritis severity scored using the Kyoto classification of gastritis was similar between the two techniques. However, in patients with current and with past Helicobacter pylori infection, color difference at the atrophic border was greater with LCI (21.58 ± 6.97 and 27.34 ± 10.32, respectively) than with WLI [14.42 ± 5.95 (p = 0.004) and 17.9 ± 8.48 (p<0.001)]; in those never infected with Helicobacter pylori, color difference at the fundic/pyloric mucosal border was greater with LCI than with WLI (p<0.001). Because of its enhancement of atrophic border detection, we recommend linked color imaging as the method of choice for transnasal endoscopy in health check-ups, particularly for identifying people at high risk of gastric cancer.

The mouth opens wide onto an additional view of immune development at mucosal borders

Much of our understanding of the way mucosal surfaces achieve a harmonious balance with their resident commensal microbiota derives from analysis of this interplay in the gut. Koren etal. (2021) interrogate the dynamics of this relationship in the mouth during early life and find that highly tissue-specific responses facilitate maturation.

The Cd8 locus Controls the Functional Conversion of CD4 Th cells to CD4 CTL in the Intestine

Abstract CD4 T cells adapt to their surroundings by differentiating into various T helper (Th) subsets. At steady state, regulatory CD4 T cells (Treg) and interleukin (IL)-17 producing CD4 T cells (Th17 cells) are present in the intestine and localize mainly to the lamina propria, whereas CD4 cytotoxic T lymphocytes (CTL) reside in the epithelium. A hallmark of CD4 CTL is the reactivation of the Cd8 locus and the re-expression of CD8a controlled by the Cd8 enhancer I (E8I). We showed before that CD4 Th cells can reprogram to CTL. Here, we elucidated a mechanism that drives the CTL reprogramming of CD4 Th cells. We identified a long noncoding RNA transcribed from the Cd8 locus, as the critical regulator of the reciprocal expression of T-BET and RUNX combined with the suppression of Foxp3 and Rorc in CD4 CTL precursors. We further found that the E8I region functions as is central coordinator of the RUNX3-controlled cytotoxic gene expression program marked by the re-expression of CD8a. Adoptive transfer of naïve E8I deletion mutant CD4 T cells to Rag1−/− recipient mice led to accelerated weight loss, and severe small and large intestine inflammation with excessive accumulation of pathogenic IL-17A and IL-17A/IFNg double producing CD4 T cells. Altogether, these findings indicate that the Cd8 locus controls the functional polarization of CD4 Th cells and furthermore, that the conversion to CTL not only enhances the direct protective capacity but also regulate the immune response and prevents excessive inflammation and immune pathology at the mucosal border of the intestine.

Thymic selection of innate self-specific T cells: Both Timing and Signal Strength matter

Abstract Naïve CD4 and CD8 T cells are selected in the thymus in response to low-avidity TCR interactions. Such weak TCR signals are crucial for installing a quiescent program that guides them to the lymph nodes yet allows for immune activation upon encounter of high-affinity ligands in the periphery. In contrast, agonist-selected T cells receive strong self-based TCR signals in the thymus that imprint them to guard the mucosal borders and maintain quiescence at steady state. Although the TCR signal strength is a decisive factor in instructing these different outcomes, the mechanism that generates protective self-specific T cells remains largely enigmatic. Previous work suggests that the self-specific double negative (DN) T cell lineage already diverges early during T cell development. We have explored the role of developmental timing by Cre-mediated deletion of components of the TCR signaling pathway. The Lck proximal promoter drives Cre expression before b-selection and the CD4 promoter drives Cre expression after b-selection but before positive selection. As TCR targets we investigated the lack of Themis expression, essential for the generation of conventional naïve T cells, but dispensable for agonist selection. Vice versa, we analyzed the requirement for Stim1 and Stim2, driving agonist selection, but not conventional selection. Both Lck prox Cre- and CD4 Cre-driven deletion of Themis lead to a drastic decrease in naïve T cells. However, DN T cells are particularly dependent on early strong TCR signals at the Pre-TCR stage, as only Lck prox Cre- but not CD4 Cre-driven deletion of Stim1/2 eliminates this subset. Our results suggest that strong signals at the Pre-TCR checkpoint are crucial for the generation of innate self-specific T cells.

An Overview of Inflammatory Bowel Disease: General Consideration and Genetic Screening Approach in Diagnosis of Early Onset Subsets.

Inflammatory bowel disease (IBD) is the consequence of an aberrant hemostasis of the immune cells at the gut mucosal border. Based on clinical manifestation, laboratory tests, radiological studies, endoscopic and histological features, this disease is divided into three main types including Crohn’s disease (CD), Ulcerative colitis (UC), and IBDunclassified (IBD-U). IBD is frequently presented in adults, but about 20% of IBD cases are diagnosed during childhood called pediatric IBD (PIBD). Some patients in the latter group emerge the first symptoms during infancy or under 5 years of age named infantile and very early onset IBD (VEO-IBD), respectively. These subtypes make a small fraction of PIBD, but they have exclusive phenotypic and genetic characteristics such that they are accompanied by severe disease course and resistance to conventional therapy.In this context, understanding the underlying molecular pathology opens a promising field for individualized and effective treatment. Here, we describe current hypotheses on IBD pathophysiology then explain the new idea about genetic screening technology as a good potential approach to identify the causal variants early in the disease manifestation, which is especially important for the fast and accurate treatment of VEO-IBD.

Limited diversity sparks inflammation at the mucosal border

Immunodeficiency in Omenn syndrome promotes microbiota-driven inflammation that can be controlled by antibiotics.

Histological and histochemical characterization on stomach of Mystus cavasius (Hamilton), Oreochromis niloticus (Linnaeus) and Gudusia chapra (Hamilton): Comparative study

The histological features and histochemical characterization of the stomach were investigated in Mystus cavasius (Hamilton), Oreochromis niloticus (Linnaeus) and Gudusia chapra (Hamilton) having different feeding habits. Histologically the stomach of all the three fishes was made up of mucosa, submucosa, muscularis and serosa. The mucosa of superficial epithelium consists of a single layer of compactly arranged columnar epithelial cells. Prominent gastric glands are present in M. cavasius whereas in G. chapra the gastric glands are totally absent in the gizzard like stomach. However, in O. niloticus tubular gastric glands are present in the glandular epithelium of caecal like stomach. The distribution and chemical nature of mucopolysaccharides in the aforementioned fishes were studied histochemically by employing Periodic Acid Schiff’s in combination with the Alcian Blue (PAS–AB) technique. Columnar epithelial cells lining the mucosa of the stomach including mucosal border were provided with exclusively neutral mucin which was probably involved in the protective functions against acid and enzymes. The different intensities of reaction of Best Carmine (BC) for glycogen in the epithelial lining and gastric glands of the stomach of the aforesaid three fish species under study were discussed. The intense reaction for protein and tryptophan was noticed in the gastric epithelium and gastric glands of M. cavasius probably due to accumulation of zymogen granules in the gastric glands. On the contrary, moderate reaction for protein and tryptophan was associated with the epithelial cells and gastric glands of O. niloticus and G. chapra. The cytoarchitecture and different degrees of localization of mucopolysaccharides, glycogen, protein and tryptophan in the stomach of M. cavasius, O. niloticus and G. chapra were correlated with the functional significance of the region concerned.

Crosstalk at the mucosal border: importance of the gut microenvironment in IBS.

The aetiology and pathology of IBS, a functional bowel disorder thought to lack an organic cause, is largely unknown. However, studies suggest that various features, such as altered composition of the gut microbiota, together with increased intestinal permeability, a changed balance in the enteroendocrine system and a dysregulated immune system in the gut, most likely have an important role in IBS. Exactly how these entities act together and give rise to symptoms is still unknown, but an altered gut microbiota composition could lead to dysregulation of the intestinal barrier as well as the enteroendocrine and the immune systems, which (through interactions with the nervous system) might generate symptoms. This Review highlights the crosstalk between the gut microbiota, the enteroendocrine system, the immune system and the role of intestinal permeability in patients with IBS.

γδ T Cells Exhibit Multifunctional and Protective Memory in Intestinal Tissues

The study of Tcell memory and the target of vaccine design have focused on memory subsumed by Tcells bearing the αβ Tcell receptor. Alternatively, γδ Tcells are thought to provide rapid immunity, particularly at mucosal borders. Here, we have shown that a distinct subset of mucosal γδ Tcells mounts an immune response to oral Listeria monocytogenes (Lm) infection and leads to the development of multifunctional memory Tcells capable of simultaneously producing interferon-γ and interleukin-17A in the murine intestinal mucosa. Challenge infection with oral Lm, but not oral Salmonella or intravenous Lm, induced rapid expansion of memory γδ Tcells, suggesting contextual specificity to the priming pathogen. Importantly, memory γδ Tcells were able to provide enhanced protection against infection. These findings illustrate that γδ Tcells play a role with hallmarks of adaptive immunity in the intestinal mucosa.

Ventral Tongue Myomucosal Flap

Squamous cell carcinoma (SCC) or verrocous carcinoma (VC) occurs frequently on the border of the lower lip and surgical excision is the mainstay of treatment. The vermilion border area is difficult to reconstruct and is very complex both morphologically and anatomically. Various reconstructive approaches for defects of the vermilion border have been described. However, for esthetics, reconstruction of the vermilion border defect by tissue of normal texture and color is paramount.We used a ventral myomucosal tongue flap for reconstruction of the vermilion border after radical excision of squamous cell carcinomas of the lip in 15 patients with labial carcinoma. The tumor was resected with a safe margin (1 cm in SCC and 0.5 cm in VC) in an approximately rectangular shape. Free-border confirmation was done using frozen section. A longitudinal strip of the free border of the tongue nonkeratinized mucosal layer with submucosal muscular layers of the tongue including the terminal branch of the lingual artery was raised. This strip extended to the angles of the mouth to cover the defect. The mucosal or myomucosal flap of the ventral tongue is designed according to the shape and size of a vermilion defect. The vermilion and subcutaneous tissue are incised, and the specimen is sent for histopathological free-border confirmation by frozen section. The flap is sutured in 2 layers, joining the mucosal border of the tongue and the upper border of the skin. The tongue flap pedicle was cut off after 3 weeks, and the oral side of the vermilion was sutured. The donor site of the tongue was closed primarily. Application of moisturizing cream for at least 2 months after surgery would be continued. In all 15 cases, the reconstructed vermilion with a tongue flap was ideal and with almost no disturbance in the patients' speaking, swallowing or taste with satisfactory cosmetic results. The ventral tongue flap is a suitable choice for vermilion border reconstruction. This flap is useful because the procedure does not require complicated surgery, and preservation of the orbicularis oris muscle and mental artery and nerve is possible.

Use of medical aural and encephalic glue-soaked gelfoam for frontal sinus repair: A single-centre experience

BackgroundFrontal sinus (FS) perforation is a common complication in frontal craniotomy. The primary goal of treatment is to seal the FS without destroying physiological function. ObjectiveThis article describes a new FS cavity reconstruction technique using medical aural and encephalic glue (EC glue)-soaked gelfoam. MethodsBetween 2007 and 2012, 118 patients underwent FS reconstruction using EC glue-soaked gelfoam. The FS cavity was reconstructed in all patients and no patient experienced intracranial infection, frontal sinusitis, or cerebrospinal fluid (CSF) leakage. ResultsRestoring physiological function is the primary goal of FS reconstruction. Difficulty often arises in sealing the sinus opening, especially when the mucosa is damaged. Mucosal border dissection and electric coagulation of the mucosal laceration can help to reconstruct the mucosal cavity. Sealing the sinus with autogenous or exogenous material, such as fascia, bone flap or gelfoam carries increased risks of intracranial infection, frontal sinusitis, and CSF leakage in the short term, and increased the occurrence of a FS mucocoele in the long term. Gelfoam saturated with EC glue obtained good results. ConclusionWe describe the application of gelfoam saturated with EC glue to treat an open FS with or without mucosal violation during frontal craniotomy. Gelfoam saturated with EC glue is a quick, effective, low-cost and reliable means of sealing the FS while preserving its physiological function.

Innate lymphoid cells: from border protection to the initiation of inflammatory diseases

Innate lymphoid cells (ILC) are a recently discovered group of innate lymphocytes found at mucosal surfaces. The transcriptional and effector programs of ILC strikingly resemble those of the various T-helper (Th) cell fates (that is, Th1, Th2, Th9, Th17, Th22). ILC are involved in protecting the mucosal borders by producing tissue protective factors. More recently, evidence has been provided that inappropriately activated ILC can be drivers of various inflammatory disorders. Here, we will highlight recent developments in our understanding of the transcriptional and developmental programs controlling ILC specification and fate decisions. We will also review the roles assigned to ILC in protecting barriers and in promoting inflammatory diseases. Finally, we will outline how the power of ILC may be harnessed for clinical application, and how interference with ILC function may be used as a new strategy to treat inflammatory diseases.

NADPH-diaphorase expression in the Meibomian glands of rat palpebra in postnatal development

In the current study, we aimed at investigating the presence of nitric oxide synthase (NOS) positive nerve fibers in rat meibomian glands (MGs) at various stages of development. There is good evidence to suggest that nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) is a surrogate for neuronal nitric oxide synthase (NOS). Sections of the central, upper eyelids of Wistar rats were processed histochemically for NADPH-d to investigate the presence and distribution of NOS-positive nerve fibers at the following time points: day 1 and weeks 1, 2 and 3 post partum, and in adult controls. At day 1, MG acini were lightly stained and located at a distance from the mucosal border. Vessels were accompanied by intensely stained NADPH-d positive nerve fibers. At the week 1 time point, both the vessels and the NADPH-d positive fibers were still present, but less numerous. MGs were now closer to the mucosa, so that the submucosa was thinner. The acini were mostly pale but occasionally darker. At week 3, there were fewer blood vessels in both the sub-mucosa and within the septa. Darker acini were more common than lightly stained acini. NADPH-d positive dots were observed in the vicinity of the MGs. At the week 3 time point, MGs were adjacent to the mucosal border and stained more intensely than at earlier times; almost all acini were stained. The microscopic appearances were almost identical with those of adult palpebra. Submucosal and septal blood vessels and NADPH-d positive nerve fibers were less numerous. NADPH-d histochemical staining confirmed differences in the density of stained nerve fibers at different developmental stages. The greatest density of NADPH-d -positive nerve fibers occurred in 1-day-old rats whereas they were less numerous in adult rat eyelids. Nerves innervating MGs utilize nitric oxide (NO) as a neurotransmitter mostly in early developmental stages and this need thereafter decreases and stabilizes at 3 weeks postnatally.

Securing Mucosal Borders—Migrant Monocytes to the Rescue

Gr1(+) "inflammatory" monocytes are emerging as key players in the innate immune response to infection and vaccination. In a recent issue of Immunity, Dunay et al. (2008) report a surprisingly crucial role for inflammatory monocytes in mucosal resistance to the parasitic agent Toxoplasma gondii.

Aesthetic vermilion reconstruction of a post-involuted hemangioma scar

The author describes a technique for vermilion reconstruction after excision of an involuted hemangioma scar in the upper lip in an adult female patient. Reconstruction was achieved by making use of all the available vermilion tissue remaining after a triangular excision of the scar. The incision is in the form of a horizontal “K” with extended limbs and repair by advancing and interdigitating the two medial and lateral triangular vermilion flaps with a final Z-shaped suture line. The advancement is like a modified double opposing Y–V plasty. This was complemented by a simple Z-plasty of the labial mucosa to correct an existing notch and deficiency of the free mucosal border. The aesthetic result was excellent; thus, its use can be considered when closing any similar defects resulting from scars or small benign lesion excisions.

The struggle for iron: gastrointestinal microbes modulate the host immune response during infection

The gastrointestinal track is one source of potential bacterial entry into the host, and the local immune system at the mucosal border is paramount in establishing host immune tolerance and the immune response to invading organisms. Macrophages use iron for production of hydroxy-radical and superoxide reactions, which are necessary for microbial killing. Presumably, as a survival strategy, bacteria, which also require iron for survival, have adapted the ability to sequester iron from the host, thereby limiting the availability to macrophages. As current modes of antimicrobial therapy are evolving, examination of nontraditional therapies is emerging. One such potential therapy involves altering the bacterial micronutrient iron concentration. Necrotizing enterocolitis is a clinical condition where such a strategy makes intuitive sense. This review will describe the immune response to gastrointestinal infection, the mechanisms that the gastrointestinal system uses to absorb intraluminal iron, and the critical role iron plays in the infectious process.