Preparation of Soluble Mucin Solutions from the Salivary Glands.

Studying salivary gland mucins is important for elucidating the pathogenesis of salivary gland diseases, including tumors and xerostomia, and developing diagnostic methods for them. Classic methods for isolating mucins from salivary glands require sacrificing several animals to obtain sufficient quantities of mucin and are time-consuming. Supported molecular matrix electrophoresis (SMME) was used to characterize mucins and their glycans. With this method, mucins can be analyzed within 2 days using less than 100 mg of tissue and without using expensive equipment, such as an ultracentrifuge. This chapter describes a method for preparing mucin solutions for SMME analysis of salivary gland mucins.

Comprehensive diagnosis and treatment of ductal carcinoma of the submandibular gland: case report and literature review.

Salivary duct carcinoma (SDC) is a rare malignant tumor of the salivary gland and is most commonly found in the parotid gland, followed by the submandibular gland. Due to its rarity, there is no consensus on its treatment. Surgical resection is currently the only curative treatment. Considering its high degree of malignancy, extensive tumor resection and postoperative adjuvant radiotherapy are recommended. We report a rare case of SDC of the submandibular gland. A 62-year-old man presented to our hospital with complaints of swelling in the right submaxillary area for 4 months, rapidly growing, with pain for 10 days. After admission, fine needle aspiration (FNA) revealed right submandibular gland ductal carcinoma. Considering its aggressiveness, large size, and invasion of parapharyngeal and oral floor soft tissues, the patient received two cycles of neoadjuvant chemotherapy followed by extended surgical resection. Postoperatively, the patient received four cycles of concurrent chemoradiotherapy, followed by afatinib targeted therapy. No recurrence or metastasis was observed in a 45-month follow-up. Thus we present a comprehensive treatment for salivary duct carcinoma combining neoadjuvant chemotherapy with surgery, postoperative concurrent radiotherapy, and chemotherapy followed by afatinib targeted therapy.

An optimized protocol for assessment of sputum macrorheology in health and muco-obstructive lung disease.

Background: Airway mucus provides important protective functions in health and abnormal viscoelasticity is a hallmark of muco-obstructive lung diseases such as cystic fibrosis (CF). However, previous studies of sputum macrorheology from healthy individuals and patients with CF using different experimental protocols yielded in part discrepant results and data on a systematic assessment across measurement settings and conditions remain limited. Objectives: The aim of this study was to develop an optimized and reliable protocol for standardized macrorheological measurements of airway mucus model systems and native human sputum from healthy individuals and patients with muco-obstructive lung disease. Methods: Oscillatory rheological shear measurements were performed using bovine submaxillary mucin (BSM) at different concentrations (2% and 10% solids) and sputum samples from healthy controls (n = 10) and patients with CF (n = 10). Viscoelastic properties were determined by amplitude and frequency sweeps at 25°C and 37°C with or without solvent trap using a cone-plate geometry. Results: Under saturated atmosphere, we did not observe any temperature-dependent differences in 2% and 10% BSM macrorheology, whereas in the absence of evaporation control 10% BSM demonstrated a significantly higher viscoelasticity at 37°C. Similarly, during the measurements without evaporation control at 37°C we observed a substantial increase in the storage modulus G' and the loss modulus G″ of the highly viscoelastic CF sputum but not in the healthy sputum. Conclusion: Our data show systematically higher viscoelasticity of CF compared to healthy sputum at 25°C and 37°C. For measurements at the higher temperature using a solvent trap to prevent evaporation is essential for macrorheological analysis of mucus model systems and native human sputum. Another interesting finding is that the viscoelastic properties are not much sensitive to the applied experimental deformation and yield robust results despite their delicate consistency. The optimized protocol resulting from this work will facilitate standardized quantitative assessment of abnormalities in viscoelastic properties of airway mucus and response to muco-active therapies in patients with CF and other muco-obstructive lung diseases.

Conjoint analysis of OPRPN and SMR3A protein expression as potential predictive biomarkers for head and neck squamous cell carcinoma after radiotherapy.

Increased submaxillary gland androgen­regulated protein 3A (SMR3A) expression was previously shown to serve as an independent risk factor for oropharyngeal squamous cell carcinoma (OPSCC) and as a surrogate biomarker for active estrogen receptor 2 signaling in radioresistant tumor cells. In the present study, it was aimed to unravel the expression and clinical significance of another member of the opiorphin family, opiorphin prepropeptide (OPRPN), in the radiotherapy for head and neck squamous cell carcinoma (HNSCC). Expression of SMR3A and OPRPN were analyzed for the prior and post fractionated irradiation (4x2 Gy) by double immunofluorescence staining in established HNSCC cell lines as well as by immunohistochemical (IHC) staining in ex vivo tumor tissues. Next, in a retrospective experimental cohort study, primary tumor samples from OPSCC patients (n=96), who received definitive surgery and adjuvant radiotherapy were reviewed, and expression levels of OPRPN protein were detected by IHC. Immunoreactivity scores (IRS) were associated with pathological and clinical risk factors by Chi­square analysis. Survival analysis was performed by using the Kaplan­Meier plot, log­rank test and Cox regression analysis. The expression levels of OPRPN and SMR3A protein were both induced by fractionated irradiation in vitro and ex vivo. In primary tumor samples, IRS of OPRPN was significantly higher than scores of SMR3A expression and positively correlated with expression patterns of SMR3A. SMR3A was confirmed to serve as an unfavorable factor, while OPRPN protein had no significant association with the clinical outcome of patients with OPSCC. A combinational analysis revealed that the subgroup with SMR3AhighOPRPNlow staining pattern had the worst clinical outcome among the various subgroups. Multivariate Cox regression analyses indicated that high expression of SMR3A serves as an independent unfavorable biomarker, while increased expression of OPRPN appears to exert protective function. In summary, the present study indicated that SMR3A and OPRPN serve as potential prognostic markers for HNSCC after radiotherapy.

Management of Ludwig's Angina at a Tertiary Care Hospital in Western Region of India.

Introduction Ludwig's angina is cellulitis of submandibular space, submental space, and sublingual space. The main causative factors include dental infections (dental caries with atypical periodontitis, pericoronitis, and dental procedures). Other predisposing conditions include poor dental hygiene, dental caries, malnutrition, diabetes mellitus, AIDS, and various other immunocompromised states. It presents as an acute onset and spreads very rapidly causing bilateral diffuse neck swelling, edema of floor of mouth, pain, fever, trismus, foul-smelling pus discharge, difficulty in swallowing, airway edema, and tongue displacement creating a compromised airway with stridor. So it requires early diagnosis and aggressive management. Material and methods Clinical data of all patients with clinical diagnosis of Ludwig's angina managed at the Department of Otorhinolaryngology-Head and Neck Surgery, Sir Takhatsinhji (T) General Hospital and Government Medical College, Bhavnagar, India, from 2015 to 2019 were analyzed retrospectively in this study. Result Over the review period, 30 cases were diagnosed as Ludwig's angina, out of which 12 (40%) were males and 18 (60%) were females; male to female ratio was 1:1.5. The age of the patients ranged from six months to 64 years, with a mean age of 38.86 years. Fever, neck swelling, and neck pain were present in all patients. In 16 patients, incision and drainage were done under general anesthesia while the rest five patients required only local anesthesia. In six patients (20%), for maintenance of airway, tracheostomy was required. The most common complication was necrotizing fasciitis and death followed by septicemia. Mortality was observed in three patients (10%) in this study. Conclusion Despite improved outcomes compare to pre-antibiotic era, Ludwig's angina still remains a potentially life-threatening disease in ENT at present. Dental caries, uncontrolled diabetes mellitus, and malnutrition are commonly associated conditions. With early diagnosis, close airway observation, aggressive intravenous antibiotic treatment, and timely surgical intervention, morbidity, and mortality can be reduced.

RNA-seq coupling two different methods of castration reveals new insights into androgen deficiency-caused degeneration of submaxillary gland in male Sprague Dawley rats.

BACKGROUND: Salivary gland (SMG) degeneration and dysfunction are common symptoms that occur after sex hormone deprivation, but the underlying mechanisms remain largely unknown. Additionally, immunocastration, which causes drop of sex hormones, has been developed as an alternative to surgical castration, however whether it exerts similar effects as surgical castration on the salivary glands is unknown. Through histological and RNA-seq analysis, we assessed changes in morphology and transcriptome of SMG in response to immunocastration (IM) versus surgical castration (bilateral orchiectomy, ORC). RESULTS: Compared to entire males (EM), ORC caused severe degeneration of SMG in rats, as evidenced by both decreased (P < 0.01) SMG weight and organ index, and by decreased (P < 0.01) quantity of SMG acini and ducts. IM had minimal effects (P > 0.05) on SMG weight and organ index, but it still caused degeneration (P < 0.05) of the acini and ducts. Even though, the quantity of both SMG acini and ducts was much higher (P < 0.001) in IM than in ORC. Functional enrichment analysis of the common regulated genes by ORC/IM revealed disrupted epithelial cell development, angiogenesis, anatomical structure morphogenesis and enhanced cell death are associated with SMG degeneration in deprivation of androgens. Integrated data analysis shown that there existed a selective hyperfunction of SMG ribosome and mitochondrion in ORC but not in IM, which might be associated with more severe degeneration of SMG in ORC than in IM. CONCLUSIONS: Our findings suggested that both surgical castration and immunocastration caused SMG degeneration by disrupting epithelial cell development, angiogenesis, anatomical structure morphogenesis and enhancing cell death. But, surgical castration selectively induced hyperfunction of SMG ribosome and mitochondrion, thus causing more severe degeneration of SMG than immunocastration.

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.

Submaxilitis aguda bilateral asociada con listeriosis en un paciente inmunodeprimido / Acute bilateral submaxillitis associated to listeriosis in immunosuppressed patient

Acute bilateral submaxillitis is a rare event, except when it is caused by sialolithiasis. It has been described secondary to allergic, infectious, suppurative or viral processes, autoimmune such as Sjögren's syndrome, drugs such as thiopurines, nitrofurantoin, phenylbutazone, captopril, and after upper airway procedures such as upper endoscopy, orotracheal intubation bronchoscopy and ERCP (endoscopic retrograde cholangiopancreatography for choledocholithiasis). Treatment with tumour necrosis factor-alpha (TNF-alpha) antagonist drugs is associated with an increased risk of reactivation of intracellular bacterial infections, so that listeriosis has been described in pathologies that require such treatment, such as rheumatic, dermatological and intestinal diseases, which present other comorbidities or are immunocompromised. Listeriosis mainly causes bacteremia and meningitis, when symptomatic, and infects immunosuppressed persons, where it has a lethality despite 30% antibiotherapy. We present the clinical case of a male immunosuppressed patient, secondary to a treatment with azathioprine and prednisone followed by adalimumab, for indeterminate inflammatory bowel disease, superinfected by CMV, who after eating meat contaminated by Listeria monocytogenes, suffered a picture of listeriosis bacteremia, which improved with antibiotic treatment, followed by a transient acute bilateral submaxillitis, which subsided with symptomatic treatment (oral hydration). It is the only case described in the literature, in which an immunosuppressed patient treated with adalimumab, suffers from acute bilateral submaxillitis in the context of listeriosis, caused by the mumps virus.

La submaxilitis aguda bilateral es un evento raro, salvo cuando está causada por sialolitiasis. Se la ha descrito secundaria a procesos alérgicos, infecciosos, supurativos, virales o autoinmunes como el síndrome de Sjögren; a la administración de fármacos como tiopurinas, nitrofurantoina, fenilbutazona, captopril, y tras procedimientos sobre la vía aérea superior, como endoscopia digestiva alta, broncoscopia, intubación orotraqueal y colangiopancreatografía retrógrada endoscópica por coledocolitiasis (CPRE). El tratamiento con fármacos antagonistas del factor de necrosis tumoral alfa (TNF-alfa) se asocia con riesgo acentuado de reactivación de infecciones bacterianas intracelulares, de forma que se ha descrito la listeriosis en afecciones que requieren dicho tratamiento, como enfermedades reumáticas, dermatológicas y del intestino en sujetos que presentaban otras comorbilidades o estaban inmunocomprometidos. La listeriosis provoca bacteriemia y meningitis predominantemente, cuando es sintomática, e infecta a los sujetos inmunodeprimidos, en los que, a pesar de la antibioticoterapia, tiene una letalidad del 30%. Se presenta el caso clínico de un paciente varón, inmunodeprimido, secundario a tratamiento por azatioprina y prednisona seguido de adalimumab, por enfermedad inflamatoria intestinal indeterminada, sobreinfectada por citomegalovirus, que tras la ingesta de carne contaminada por Listeria monocytogenes, sufrió un cuadro de bacteriemia por listeriosis que mejoró con tratamiento con antibióticos, seguido de submaxilitis aguda bilateral transitoria, que cedió con tratamiento sintomático (hidratación oral). Es el único caso descrito en la literatura en el que un paciente inmunodeprimido tratado con adalimumab presenta submaxilitis aguda bilateral en el contexto de la listeriosis, provocada por el virus de la parotiditis.

Structural and Quantitative Characterization of Mucin-Type O-Glycans and the Identification of O-Glycosylation Sites in Bovine Submaxillary Mucin.

Bovine submaxillary mucin (BSM) is a gel-forming glycoprotein polymer, and Ser/Thr-linked glycans (O-glycans) are important in regulating BSM's viscoelasticity and polymerization. However, details of O-glycosylation have not been reported. This study investigates the structural and quantitative characteristics of O-glycans and identifies O-glycosylation sites in BSM using liquid chromatography-tandem mass spectrometry. The O-glycans (consisting of di- to octa-saccharides) and their quantities (%) relative to total O-glycans (100%; 1.1 pmol per 1 µg of BSM) were identified with 14 major (>1.0%), 12 minor (0.1%-1.0%), and eight trace (<0.1%) O-glycans, which were characterized based on their constituents (sialylation (14 O-glycans; 81.9%, sum of relative quantities of each glycan), non-sialylation (20; 18.1%), fucosylation (20; 17.5%), and terminal-galactosylation (6; 3.6%)) and six core structure types [Gal-GalNAc, Gal-(GlcNAc)GalNAc, GlcNAc-GalNAc, GlcNAc-(GlcNAc)GalNAc, and GalNAc-GalNAc]. O-glycosylation sites were identified using O-glycopeptides (bold underlined; 56SGETRTSVI, 259SHSSSGRSRTI, 272GSPSSVSSAEQI, 307RPSYGAL, 625QTLGPL, 728TMTTRTSVVV, and 1080RPEDNTAVA) obtained from proteolytic BSM; these sites are in the four domains of BSM. The gel-forming mucins share common domain structures and glycosylation patterns; these results could provide useful information on mucin-type O-glycans. This is the first study to characterize O-glycans and identify O-glycosylation sites in BSM.

Botulinum Neurotoxins and Cancer-A Review of the Literature.

Botulinum neurotoxins (BoNT) possess an analgesic effect through several mechanisms including an inhibition of acetylcholine release from the neuromuscular junction as well as an inhibition of specific pain transmitters and mediators. Animal studies have shown that a peripheral injection of BoNTs impairs the release of major pain transmitters such as substance P, calcitonin gene related peptide (CGRP) and glutamate from peripheral nerve endings as well as peripheral and central neurons (dorsal root ganglia and spinal cord). These effects lead to pain relief via the reduction of peripheral and central sensitization both of which reflect important mechanisms of pain chronicity. This review provides updated information about the effect of botulinum toxin injection on local pain caused by cancer, painful muscle spasms from a remote cancer, and pain at the site of cancer surgery and radiation. The data from the literature suggests that the local injection of BoNTs improves muscle spasms caused by cancerous mass lesions and alleviates the post-operative neuropathic pain at the site of surgery and radiation. It also helps repair the parotid damage (fistula, sialocele) caused by facial surgery and radiation and improves post-parotidectomy gustatory hyperhidrosis. The limited literature that suggests adding botulinum toxins to cell culture slows/halts the growth of certain cancer cells is also reviewed and discussed.

N-Glycan Modifications with Negative Charge in a Natural Polymer Mucin from Bovine Submaxillary Glands, and Their Structural Role.

Bovine submaxillary mucin (BSM) is a natural polymer used in biomaterial applications for its viscoelasticity, lubricity, biocompatibility, and biodegradability. N-glycans are important for mucin stability and function, but their structures have not been fully characterized, unlike that of O-glycans. In this study, BSM N-glycans were investigated using liquid chromatography-tandem mass spectrometry. The microheterogeneous structures of 32 N-glycans were identified, and the quantities (%) of each N-glycan relative to total N-glycans (100%) were obtained. The terminal N-acetylgalactosamines in 12 N-glycans (sum of relative quantities; 27.9%) were modified with mono- (10 glycans) and disulfations (2 glycans). Total concentration of all sulfated N-glycans was 6.1 pmol in BSM (20 µg), corresponding to 25.3% of all negatively charged glycans (sum of present N-glycans and reported O-glycans). No N-glycans with sialylated or phosphorylated forms were identified, and sulfate modification ions were the only negative charges in BSM N-glycans. Mucin structures, including sulfated N-glycans located in the hydrophobic terminal regions, were indicated. This is the first study to identify the structures and quantities of 12 sulfated N-glycans in natural mucins. These sulfations play important structural roles in hydration, viscoelasticity control, protection from bacterial sialidases, and polymer stabilization to support the functionality of BSM via electrostatic interactions.

Submaxillary Mucin: its Effect on Aroma Release from Acidic Drinks and New Insight into the Effect of Aroma Compounds on its Macromolecular Integrity.

Submaxillary mucin is a major component that defines the makeup and functionality of saliva. Understanding its structure and function during food intake is key to designing appropriate strategies for enhancing the delivery of flavour. In the present study, the hydrodynamic integrity of bovine submaxillary mucin was characterised under physiological and acidic conditions and it was shown to have a broad molecular weight distribution with species ranging from 100 kDa to over 2000 kDa, and a random coil type of conformation. A decrease in the pH of mucin appeared to result in aggregation and a broader molecular weight distribution, which was shown to correlate with a release of flavour compounds. Our study also provides indications that p-cresol may have an effect on the macromolecular integrity of mucin.

N-glycans of bovine submaxillary mucin contain core-fucosylated and sulfated glycans but not sialylated glycans.

Bovine submaxillary mucin (BSM) is a heavily-glycosylated macromolecular (approximately 4 MDa) protein and is used in various biomaterial applications in light of its high viscosity and biocompatibility, in addition to use as a biochemical substrate or inhibitor as a result of its abundant O-glycans. Although it has been reported that N-glycosylation provides stability of human mucins, most BSM research has been focused on its O-glycans, while N-glycans have not been reported to date. In this study, a common N-glycan core component was detected by monosaccharide analysis of BSM, and the structures of the N-glycans and their relative quantities were determined by liquid chromatography-tandem mass spectrometry. Seventeen N-glycans comprising ten complex-type [Fucose0~2Hexose3~4N-acetylhexosamine1~6Sulfate0~1; 61.1% (the sum of the relative quantities of each N-glycan out of the total N-glycans)], two high-mannose-type (Hexose5~6N-acetylhexosamine2; 12.0%), and five paucimannose type (Fucose0~1Hexose3~4N-acetylhexosamine2~3; 26.9%) were identified, but no hybrid-type or sialylated N-glycans were found. Additionally, these are less-branched structures compared to human mucins. Of these, ten glycans (77.2%), including two sulfated glycans (8.0%), were core fucosylated, which confer unique biological functions to glycoproteins. The N-glycosylation sites were identified from the analysis of glycopeptides from BSM. This study is the first confirmation of N-glycan attachment to BSM.

Transoral Sialolitectomy as an Alternative to Submaxilectomy in the Treatment of Submaxillary Sialolithiasis.

INTRODUCTION: Sialolithiasis is the most common pathology in the submaxillary gland. The introduction of minimally invasive techniques isolated or associated with sialoendoscopy is replacing glandular resection as a treatment. The conservation of the gland is justified by the recovery of function and a low recurrence rate. The rate of complications is lower in conservative techniques than in submandibular gland resection. PATIENTS AND METHODS: Thirty-three patients with fixed stones in the hilum of the submaxillary gland were treated by transoral sialolitectomy between July 2015 and July 2018, demographic data of the patients such as the number of stones, size, time of hospital stay, complications, pre- and postoperative lingual nerve function, and lithiasis recurrence were collected. RESULTS: The average volume of the stones was 1.02 cm. Complete removal of the stone was possible in 32 patients. All the patients were operated in the outpatient clinic. Seven (21%) patients reported some degree of alteration of the lingual nerve function, of which the only one presented a persistence of more than 4 weeks due to an inadvertent injury that required a microsurgical anastomosis. CONCLUSIONS: Transoral sialolitectomy is a reproducible technique with good results and lower complication rates than submandibular gland resection. Our results in the first 33 cases encourage us to maintain the combined techniques as standard in the treatment of submaxillary sialolithiasis. Current experience guides the definitive substitution of submandibular gland resection by conservative techniques in obstructive pathology.

Transoral sialolitectomy combined with sialoendoscopy versus open submaxilectomy for the management of hilar lithiasis of the submandibular gland. / Sialolitectomía transoral combinada con sialoendoscopia versus submaxilectomía abierta para el manejo de litiasis hiliares de la glándula submaxilar.

INTRODUCTION: The treatment of salivary obstructive pathology by minimally invasive techniques has been an object of assessment by different studies for decades. Lithiasis at the level of the salivary duct will be the most frequent cause of obstruction, representing more than 50% of the pathology of the major salivary glands and almost 80% of these affecting the Wharton duct. MATERIAL AND METHODS: A prospective study comparing the results of combined transoral sialolitectomy (CTS) and open submaxillectomy techniques by cervicotomy in 2 groups of patients treated by lithiasis at the level of the hilum of the submaxillary gland. RESULTS: 22 patients were included in the study 16 (72.7%) were men and 6 (27.3%) were women, the average age was 54.41 years ± 12.75 (Min: 30/Max: 77). Regarding the variables associated with the disease: average lithiasis, size of the stone, hospital stay, lingual nerve alteration or complications for both techniques, differences were not found between both groups. There were only statistically significant differences in the average stay in favor of the CTS (P=.001). CONCLUSION: The minimally invasive approaches to the salivary ductal system, associated or not with sialoendoscopy, can be efficacy and can be associated with lower number of complications. The natural tendency should be aimed to gradually replacing open sialoadenectomy techniques, reserving its indication for the treatment of tumor pathology.

Migration of an Ingested Fish Bone to the Submandibular Gland: A Case Report and Literature Review.

BACKGROUND: Fish bone is one of the most common foreign bodies that gets lodged in the upper digestive tract, often located in the tonsil, epiglottis, pear-shaped fossa, and esophagus, where it may be easily located on routine inspection and removed. The forcible swallowing of food such as rice balls after ingesting fish bones by mistake may lead to the migration of the fish bone from the pharynx, throat, or esophagus to the surrounding tissues. Migration most commonly occurs to the soft tissues of the neck, even to the thyroid gland, but migration to the submandibular gland has rarely been reported. CONCLUSIONS: Foreign body ingestion may cause a series of complications and endanger a patient's life. Cases require high awareness and attentiveness on the part of the first physician to diagnose and manage the condition, and appropriate health education should be imparted to the patient.

De-O-Acetylation of mucin-derived sialic acids by recombinant NanS-p esterases of Escherichia coli O157:H7 strain EDL933.

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 strain EDL933 encodes the single chromosomal 9-O-acetylesterase NanS, and several copies of prophage-encoded 9-O-acetylesterases (NanS-p). These enzymes have recently been shown to cleave 5-N-acetyl-9-O-acetyl neuraminic acid (Neu5,9Ac2) to yield de-O-acetylated Neu5Ac, the latter of which may serve as a carbon and/or nitrogen source. In the current study, we investigated the NanS- and NanS-p-mediated digestion of synthetic O-acetylated neuraminic acids and bovine submaxillary glands mucin (BSM)-derived O-acetylneuraminic acids by high-performance thin-layer chromatography (HPTLC) and nano electrospray ionization mass spectrometry (nanoESI MS). Initial HPTLC analyses showed the expected activity of NanS and NanS-p variants for Neu5,9Ac2. However, all tested enzymes were unable to de-O-acetylate 5-N-acetyl-4-O-acetylneuraminic acid (Neu5,4 Ac2) in our test system. The nanoESI MS analysis of neuraminic acids after treatment of BSM with NanS-p gave evidence that NanS-p variants of EHEC O157:H7 strain EDL933 cleave off O-acetyl groups from mono-, di-, and tri-O-acetylated Neu5Ac and N-glycolylneuraminic acid (Neu5Gc), regardless of the carbon positions C7, C8 or C9 of the acetate esters. This enzyme activity leads to neuraminidase-accessible Neu5Ac and Neu5Gc on mucin glycans. Moreover, we could demonstrate by HPTLC analyses that recombinant Bacteroides thetaiotaomicron sialidase (BTSA-His) was able to cleave Neu5Ac and Neu5,9Ac2 from BSM and that the combination of BTSA-His with both NanS-His and NanS-p-His derivatives enhanced the release of de-O-acetylated core Neu5Ac and Neu5Gc from mammalian mucin O-glycans. Growth experiments with EHEC wildtype strain EDL933, its nanS and nanS/nanS-p1a-p7 mutant and exogenous BTSA-His in BSM demonstrated that the presence of BTSA-His enhanced growth of EDL933 and the nanS deletion mutant but not the nanS/nanS-p1a-p7 mutant. Thus, we hypothesize that the expression of sialic acid O-acetylesterases with a broad specificity could be an advantage in competition with the gut microbiota for nutrients and facilitate EHEC colonization in the human large intestine.

Endoscope-assisted resection of thyroglossal duct cysts via a submaxillary vestibular approach.

BACKGROUND: Thyroglossal duct cysts (TDCs) are usually resected through an incision over the entire protruding zone. The resulting scar is aesthetically displeasing, so we explored the use of endoscope-assisted excision of TDCs via a submaxillary vestibular approach. The purpose of this study was to demonstrate the feasibility, validity, and safety of this approach and to evaluate the follow-up results. METHODS: From January 2007 to August 2015, 16 patients with TDCs underwent surgical resection using a submaxillary vestibular approach. RESULTS: All procedures were successfully performed using endoscope-assisted surgery via a submaxillary vestibular approach. There were no postoperative complications and no conversions of the operation. The average follow-up period was 73 months (range 14-117 months) without recurrence. All patients and their families were satisfied with the cosmetic results. CONCLUSION: Endoscope-assisted excision of TDCs using a submaxillary vestibular approach is feasible and can be applied effectively and safely with good cosmetic results. Therefore, this method should be considered a viable alternative approach for these patients.

Nursing care of a child with extremely severe aplastic anemia accociated with submaxillary skin soft tissue infection / 中国实用护理杂志

Objective To summarize the nursing experience of a case of child with extremely severe aplastic anemia associated with submaxillary skin soft tissue infection, providing references for clinical care. Methods On the basis of the comprehensive cooperation to anti-infective therapy,the nurses adopt autolysis debridement and use silver ion foam dressing for the wound and also provide child with nutritional guidance and psychological support. Results After the targeted treatment the wound healed within one month, the child was transferred to the transplant ward. Conclusions The practice of this case shows that above methods are effective to control extremely severe aplastic anemia associated with submaxillary skin soft tissue infection.

Assessment of the hardness of salivary gland lesions in patients with Sj?gren′s syndrome by real-time shear wave elastography / 中华超声影像学杂志

Objective To investigate the clinical value of the real-time shear wave elastography(RT-SWE) in the assessment of salivary gland lesions by measuring the hardness of parotid gland and submaxillary gland in patients with Sj?gren′s syndrome (SS). Methods Forty patients with SS were chosen as SS group,and 35 age and gender matched healthy volunteers were chosen as control group.The patients were divided into mild SS group ( n =18) and severe SS group ( n =22) according to the decrease of uptake and secretion of salivary gland in Salivary gland scintigraphy.The Supersonic AixPlorer real-time quantitative diagnostic shear wave elastography was used to detect the parotid gland and submaxillary gland in 35 healthy volunteers and 40 patients.The RT-SWE elasticity indices of mean(Emean) was obtained and draw the SWE technology in the diagnosis of mild and severe SS patients with parotid and submandibular glands of the ROC curves. Results ① There was no significant difference in the Emean of left and right glands among the three groups (all P > 0.05). The Emean of parotid gland and submaxillary gland in patients with SS was higher than that in control group,especially in the severe SS group(all P <0.05). ②The cutoff value,sensitivity,specificity and the area under ROC for Emean with SWE diagnosing the parotid gland lesions of mild SS were 7.75 kPa,94.4%,97.1% and 0.998,and those in severe SS were 10.65 kPa, 90.9%,97.1% and 0.999,respectively.The cutoff value,sensitivity,specificity and the area under ROC for Emean with SWE diagnosing the the submaxillary glands lesions of mild SS were 8.15 kPa,100%,91.4%and 0.998,and those in severe SS were 10.40 kPa,95.5%,88.6% and 0.994,respectively.Conclusions RT-SWE can be successfully applied to assess parotid gland and submaxillary gland′s hardness in patients with SS,and provide a new method for the clinical evaluation of salivary gland diffuse lesions.