Cox regression with linked data.

Record linkage is increasingly used, especially in medical studies, to combine data from different databases that refer to the same entities. The linked data can bring analysts novel and valuable knowledge that is impossible to obtain from a single database. However, linkage errors are usually unavoidable, regardless of record linkage methods, and ignoring these errors may lead to biased estimates. While different methods have been developed to deal with the linkage errors in the generalized linear model, there is not much interest on Cox regression model, although this is one of the most important statistical models in clinical and epidemiological research. In this work, we propose an adjusted estimating equation for secondary Cox regression analysis, where linked data have been prepared by a third-party operator, and no information on matching variables is available to the analyst. Through a Monte Carlo simulation study, the proposed method is shown to lead to substantial bias reductions in the estimation of the parameters of the Cox model caused by false links. An asymptotically unbiased variance estimator for the adjusted estimators of Cox regression coefficients is also proposed. Finally, the proposed method is applied to a linked database from the Brest stroke registry in France.

Decreased syntaxin17 expression contributes to the pathogenesis of acute pancreatitis in murine models by impairing autophagic degradation.

Acute pancreatitis (AP) is an inflammatory disease of the exocrine pancreas. Disruptions in organelle homeostasis, including macroautophagy/autophagy dysfunction and endoplasmic reticulum (ER) stress, have been implicated in human and rodent pancreatitis. Syntaxin 17 (STX17) belongs to the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) subfamily. The Qa-SNARE STX17 is an autophagosomal SNARE protein that interacts with SNAP29 (Qbc-SNARE) and the lysosomal SNARE VAMP8 (R-SNARE) to drive autophagosome-lysosome fusion. In this study, we investigated the role of STX17 in the pathogenesis of AP in male mice or rats induced by repeated intraperitoneal injections of cerulein. We showed that cerulein hyperstimulation induced AP in mouse and rat models, which was characterized by increased serum amylase and lipase activities, pancreatic edema, necrotic cell death and the infiltration of inflammatory cells, as well as markedly decreased pancreatic STX17 expression. A similar reduction in STX17 levels was observed in primary and AR42J pancreatic acinar cells treated with CCK (100 nM) in vitro. By analyzing autophagic flux, we found that the decrease in STX17 blocked autophagosome-lysosome fusion and autophagic degradation, as well as the activation of ER stress. Pancreas-specific STX17 knockdown using adenovirus-shSTX17 further exacerbated pancreatic edema, inflammatory cell infiltration and necrotic cell death after cerulein injection. These data demonstrate a critical role of STX17 in maintaining pancreatic homeostasis and provide new evidence that autophagy serves as a protective mechanism against AP.

Effects of SPARCL1 on the proliferation and differentiation of sheep preadipocytes.

Important candidate genes that regulate lipid metabolism have the potential to increase the content of intramuscular fat (IMF) and improve meat quality. Secreted protein acidic and rich in cysteine like 1(SPARCL1) is a secreted glycoprotein with important physiological functions and is involved in the proliferation and differentiation of various cells. However, the role of the SPARCL1 gene in sheep preadipocytes and its regulatory mechanism is still unclear. In this study, we explored the effect of SPARCL1 on the proliferation and differentiation of sheep preadipocytes. The results showed that the expression level of the SPARCL1 gene is higher in fat tissue than in other tissues, and the gene was significantly increased on the 6th day of preadipocyte differentiation. In the preadipocyte proliferation stage, interference of SPARCL1 gene reduced cell viability and increased cell apoptosis. In preadipocyte differentiation stage, SPARCL1 overexpression significantly inhibited lipid droplets accumulation and triglyceride content by increasing Wnt10b, Fzd8, IL6, and ß-catenin and inhibiting PPARγ, C/EBPα, LPL, and IGF1 genes expression, whereas SPARCL1 deficiency significantly promoted cell differentiation by inhibiting ß-catenin and increasing GSK3ß, PPARγ, C/EBPα, and LPL. The results of this study suggest that SPARCL1 plays a negative role during preadipocyte differentiation and may become a novel target for regulating preadipocyte differentiation and improving IMF.Abbreviations:IMF: Intramuscular fat SPARCL1: Secreted protein acidic and rich in cysteine like 1 PPARγ: Peroxisome proliferator-activated receptor γ C/EBPα: CCAAT/enhancer-binding protein-α LPL: Lipoprotein lipase IGF1: Insulin-like growth factor 1 Wnt10b: Wnt family member 10B Fzd8: Frizzled class receptor 8 IL6: Interleukin 6 ß-catenin: Catenin beta interacting protein 1 GSK3ß: Glycogen synthase kinase 3 beta LRP5/6: Low-density lipoprotein receptor-related protein 5/6.

Whole-Transcriptome Analysis of Preadipocyte and Adipocyte and Construction of Regulatory Networks to Investigate Lipid Metabolism in Sheep.

Many local sheep breeds in China have poor meat quality. Increasing intramuscular fat (IMF) content can significantly improve the quality of mutton. However, the molecular mechanisms of intramuscular adipocyte formation and differentiation remain unclear. This study compared differences between preadipocytes and mature adipocytes by whole-transcriptome sequencing and constructed systematically regulatory networks according to the relationship predicted among the differentially expressed RNAs (DERs). Sequencing results showed that in this process, there were 1,196, 754, 100, and 17 differentially expressed messenger RNAs (mRNAs), long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), respectively. Gene Ontology analysis showed that most DERs enriched in Cell Part, Cellular Process, Biological Regulation, and Binding terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis found that the DERs primarily focused on Focal adhesion, phosphoinositide 3-kinase (PI3K)-Akt, mitogen-activated protein kinase (MAPK), peroxisome proliferator-activated receptor (PPAR) signaling pathways. Forty (40) DERs were randomly selected from the core regulatory network to verify the accuracy of the sequence data. The results of qPCR showed that the DER expression trend was consistent with sequence data. Four novel promising candidate miRNAs (miR-336, miR-422, miR-578, and miR-722) played crucial roles in adipocyte differentiation, and they also participated in multiple and important regulatory networks. We verified the expression pattern of the miRNAs and related pathways' members at five time points in the adipocyte differentiation process (0, 2, 4, 6, 8, 10 days) by qPCR, including miR-336/ACSL4/LncRNA-MSTRG71379/circRNA0002331, miR-422/FOXO4/LncRNA-MSTRG54995/circRNA0000520, miR-578/IGF1/LncRNA-MSTRG102235/circRNA0002971, and miR-722/PDK4/LncRNA-MSTRG107440/circ RNA0002909. In this study, our data provided plenty of valuable candidate DERs and regulatory networks for researching the molecular mechanisms of sheep adipocyte differentiation and will assist studies in improving the IMF.

Protective effects of SOD2 overexpression in human umbilical cord mesenchymal stem cells on lung injury induced by acute paraquat poisoning in rats.

AIMS: To study the protective effects and mechanisms of human umbilical cord mesenchymal stem cells (hUCMSCs) and overexpression of antioxidant gene SOD2 on lung injury by establishing a rat model of paraquat (PQ)-induced lung injury. MAIN METHODS: The hUCMSCs cell line overexpressed SOD2 was established. After intraperitoneal injection of PQ solution (24 mg/kg) 3 h later, the different groups of hUCMSCs cell lines were injected through the tail veins of rats. Bronchoalveolar lavage fluid (BALF) was obtained to determine the protein level of inflammatory cytokines. Lung tissues were collected to test the wet/dry weight ratios (W/D), oxidative stress index and lung injury scores. Western blotting was used to detect SOD1, SOD2, HO-1, Nrf2, NF-κBp65 subunit, and cleaved caspase-3. KEY FINDINGS: After treatment with cells built on the basis of hUCMSCs, the protein levels of TNF-α, IL-8, and ICAM-1 in BALF decreased, and meanwhile in lung tissues, MDA content was reduced, GSH-Px activity was elevated, and lung W/D ratio decreased. Additionally, protein expression of NF-κB p65 subunit and activated caspase-3 in lung tissues was down-regulated, whereas expression of SOD1, SOD2, HO-1, and Nrf-2 were up-regulated. The results of HE staining showed that lung injury was significantly alleviated in the hUCMSC treated group. It is noticeable that hUCMSCs and SOD2-overexpressed hUCMSCs effectively reduced PQ-induced lung injury in rats, and moreover, hUCMSCs overexpressed SOD2 were more effective compared with hUCMSCs only. SIGNIFICANCE: Evaluation of the efficacy and analysis of mechanism in the treatment of PQ induced ALI by appliance of SOD2-overexpressed hUCMSCs will provide the proof from bench to bedside.

GUILD: GUidance for Information about Linking Data sets.

Record linkage of administrative and survey data is increasingly used to generate evidence to inform policy and services. Although a powerful and efficient way of generating new information from existing data sets, errors related to data processing before, during and after linkage can bias results. However, researchers and users of linked data rarely have access to information that can be used to assess these biases or take them into account in analyses. As linked administrative data are increasingly used to provide evidence to guide policy and services, linkage error, which disproportionately affects disadvantaged groups, can undermine evidence for public health. We convened a group of researchers and experts from government data providers to develop guidance about the information that needs to be made available about the data linkage process, by data providers, data linkers, analysts and the researchers who write reports. The guidance goes beyond recommendations for information to be included in research reports. Our aim is to raise awareness of information that may be required at each step of the linkage pathway to improve the transparency, reproducibility, and accuracy of linkage processes, and the validity of analyses and interpretation of results.

Disentangling age-gender interactions associated with risks of fatal and non-fatal road traffic injuries in the Sultanate of Oman.

OBJECTIVE: Road traffic injuries (RTIs) are the leading cause of disability-adjusted life years lost in Oman, Saudi Arabia and United Arab Emirates. Injury prevention strategies often overlook the interaction of individual and behavioural risk factors in assessing the severity of RTI outcomes. We conducted a systematic investigation of the underlying interactive effects of age and gender on the severity of fatal and non-fatal RTI outcomes in the Sultanate of Oman. METHODS: We used the Royal Oman Police national database of road traffic crashes for the period 2010-2014. Our study was based on 35 785 registered incidents: of these, 10.2% fatal injuries, 6.2% serious, 27.3% moderate, 37.3% mild injuries and 19% only vehicle damage but no human injuries. We applied a generalised ordered logit regression to estimate the effect of age and gender on RTI severity, controlling for risk behaviours, personal characteristics, vehicle, road, traffic, environment conditions and geographical location. RESULTS: The most dominant group at risk of all types of RTIs was young male drivers. The probability of severe incapacitating injuries was the highest for drivers aged 25-29 (26.6%) years, whereas the probability of fatal injuries was the highest for those aged 20-24 (26.9%) years. Analysis of three-way interactions of age, gender and causes of crash show that overspeeding was the primary cause of different types of RTIs. In particular, the probability of fatal injuries among male drivers attributed to overspeeding ranged from 3%-6% for those aged 35 years and above to 13.4% and 17.7% for those aged 25-29 years and 20-24 years, respectively. CONCLUSIONS: The high burden of severe and fatal RTIs in Oman was primarily attributed to overspeed driving behaviour of young male drivers in the 20-29 years age range. Our findings highlight the critical need for designing early gender-sensitive road safety interventions targeting young male and female drivers.

Telecommunication Wavelength-Band Single-Photon Emission from Single Large InAs Quantum Dots Nucleated on Low-Density Seed Quantum Dots.

Single-photon emission in the telecommunication wavelength band is realized with self-assembled strain-coupled bilayer InAs quantum dots (QDs) embedded in a planar microcavity on GaAs substrate. Low-density large QDs in the upper layer active for ~1.3 µm emission are fabricated by precisely controlling the indium deposition amount and applying a gradient indium flux in both QD layers. Time-resolved photoluminescence (PL) intensity suggested that the radiative lifetime of their exciton emission is 1.5~1.6 ns. The second-order correlation function of g (2)(0) < 0.5 which demonstrates a pure single-photon emission.

In situ probing and integration of single self-assembled quantum dots-in-nanowires for quantum photonics.

The realization of fiber-output single photon sources is necessary for quantum photonics. Here we present in situ probing and integration of single self-assembled quantum dots (QDs)-in-nanowires. Single self-assembled AlGaAs QDs were synthesized in GaAs/AlGaAs core-shell nanowires by molecular beam epitaxy and characterized by optical excitation in both micro-PL and fiber-integrating set-up. Cascaded biexciton-exciton emission with a saturation signal of 1000 counts per second at nitrogen temperature is achieved through the fiber-integrating setup, which makes single mode fibers an ideal candidate for single photons sources and paves the way for the realization of 'all fiber' devices. Numerical calculations were carried out to illustrate the collection efficiency and polarized photoluminescence characteristics. Extraction efficiencies as high as 70% over a broadband emission are reported and increase by a factor of about seven in comparison with air extraction, due to the larger refractive index of the fiber core.

Morphological engineering of self-assembled nanostructures at nanoscale on faceted GaAs nanowires by droplet epitaxy.

Fabrication of advanced artificial nanomaterials is a long-term pursuit to fulfill the promises of nanomaterials and it is of utter importance to manipulate materials at nanoscale to meet urgent demands of nanostructures with designed properties. Herein, we demonstrate the morphological tailoring of self-assembled nanostructures on faceted GaAs nanowires (NWs). The NWs are deposited on different kinds of substrates. Triangular and hexagonal prism morphologies are obtained, and their corresponding {110} sidewalls act as platforms for the nucleation of gallium droplets (GDs). We demonstrate that the morphologies of the nanostructures depend not only on the annealing conditions but also on the morphologies of the NWs' sidewalls. Here, we achieve morphological engineering in the form of novel quantum dots (QDs), 'square' quantum rings (QRs), 'rectangular' QRs, 3D QRs, crescent-shaped QRs, and nano-antidots. The evolution mechanisms for the peculiar morphologies of both NWs and nanostructures are modeled and discussed in detail. This work shows the potential of combining nano-structural engineering with NWs to achieve multifunctional properties and applications.

Multiresidue Determination of ß2-Agonists Including Phenylethanolamine A in Animal-Derived Food by Ultra-High Performance Liquid Chromatography/Tandem Mass Spectrometry.

A comprehensive ultra-high performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS) procedure for detection of nine ß-agonists in animal-derived food is described. The method was based on enzymatic hydrolysis with ß-glucuronidase from Helix pomatia, followed by a liquid-liquid extraction procedure with perchloric acid and a solid-phase extraction scheme using two kinds of cartridges, HLB and MCX. The influence of sample solution pH in the extraction recovery was studied, and pH 4.0 was found to give the best recovery. The analytes were eluted with methanol containing 4% ammonia. A validation procedure for quantitative analysis of ß-agonists in animal-derived food was performed. The three kinds of internal standards, d3-salbutamol, d6-ractopamine and d9-clenpenterol, were applied in the sample preparation and detection of UHPLC/MS/MS. The recoveries from spiked samples ranged between 74.9 and 106.9%. The relative standard deviations of detection were at 0.7-9.6%. The limits of detection and quantification were 0.01-0.05 and 0.03-0.20 µg/kg, respectively. The effect of sample matrix in the detection was discussed in detail.

A comparison of three MDCT post-processing protocols: preoperative assessment of the ossicular chain in otitis media.

The aim of this study was to examine and assess comparative values of HRCT-based multiplanar reformation (MPR), volume rendering (VR) and virtual endoscope built on three-dimensional (3D) shaded-surface display (SSD-based CTVE) for detections of ossicular chain's damage in patients with otitis media. 70 human ears from 70 patients suffering by chronic otitis media or cholesteatoma, who were examined with a preoperative multi-slice computer tomography (MSCT) examination and tympanoplasty in our hospital were collected. The patients ossicular chains were reconstructed with the aforementioned three protocols and assessed via a three-point scoring system by three radiologists. Then, all the patients ossicular chains were reviewed by a surgeon and a radiologist via the same three-point scoring system used during surgeries at same time. By calculation, the Youden's index and coincidence rate were acquired without a significant difference for display of malleus. With regard to the incus, the Youden's index and coincidence rate of VR and MPR did not show any difference, however, both were higher than CTVE. For representation of the stapes, the accuracy of these three modalities is very low; especially, for the CTVE. In conclusion, both MPR and VR are relative robust, and CTVE is not effective for evaluation of small ossicular structures, particularly the stapes. Furthermore, the VR images are real 3D ones. Therefore, it could be the more valuable protocols for detection of the damage of ossicular chain in the patients with otitis media, and should be further applied in the future work.

Diversity and taxonomy of endophytic xylariaceous fungi from medicinal plants of Dendrobium (Orchidaceae).

Dendrobium spp. are traditional Chinese medicinal plants, and the main effective ingredients (polysaccharides and alkaloids) have pharmacologic effects on gastritis infection, cancer, and anti-aging. Previously, we confirmed endophytic xylariaceous fungi as the dominant fungi in several Dendrobium species of tropical regions from China. In the present study, the diversity, taxonomy, and distribution of culturable endophytic xylariaceous fungi associated with seven medicinal species of Dendrobium (Orchidaceae) were investigated. Among the 961 endophytes newly isolated, 217 xylariaceous fungi (morphotaxa) were identified using morphological and molecular methods. The phylogenetic tree constructed using nuclear ribosomal internal transcribed spacer (ITS), large subunit of ribosomal DNA (LSU), and beta-tubulin sequences divided these anamorphic xylariaceous isolates into at least 18 operational taxonomic units (OTUs). The diversity of the endophytic xylariaceous fungi in these seven Dendrobium species was estimated using Shannon and evenness indices, with the results indicating that the dominant Xylariaceae taxa in each Dendrobium species were greatly different, though common xylariaceous fungi were found in several Dendrobium species. These findings implied that different host plants in the same habitats exhibit a preference and selectivity for their fungal partners. Using culture-dependent approaches, these xylariaceous isolates may be important sources for the future screening of new natural products and drug discovery.

Sclerotial formation of Polyporus umbellatus by low temperature treatment under artificial conditions.

BACKGROUND: Polyporus umbellatus sclerotia have been used as a diuretic agent in China for over two thousand years. A shortage of the natural P. umbellatus has prompted researchers to induce sclerotial formation in the laboratory. METHODOLOGY/PRINCIPAL FINDING: P. umbellatus cultivation in a sawdust-based substrate was investigated to evaluate the effect of low temperature conditions on sclerotial formation. A phenol-sulfuric acid method was employed to determine the polysaccharide content of wild P. umbellatus sclerotia and mycelia and sclerotia grown in low-temperature treatments. In addition, reactive oxygen species (ROS) content, expressed as the fluorescence intensity of mycelia during sclerotial differentiation was determined. Analysis of ROS generation and sclerotial formation in mycelia after treatment with the antioxidants such as diphenyleneiodonium chloride (DPI), apocynin (Apo), or vitamin C were studied. Furthermore, macroscopic and microscopic characteristics of sclerotial differentiation were observed. Sclerotia were not induced by continuous cultivation at 25°C. The polysaccharide content of the artificial sclerotia is 78% of that of wild sclerotia. In the low-temperature treatment group, the fluorescent intensity of ROS was higher than that of the room temperature (25°C) group which did not induce sclerotial formation all through the cultivation. The antioxidants DPI and Apo reduced ROS levels and did not induce sclerotial formation. Although the concentration-dependent effects of vitamin C (5-15 mg mL(-1)) also reduced ROS generation and inhibited sclerotial formation, using a low concentration of vitamin C (1 mg mL(-1)) successfully induced sclerotial differentiation and increased ROS production. CONCLUSIONS/SIGNIFICANCE: Exposure to low temperatures induced P. umbellatus sclerotial morphogenesis during cultivation. Low temperature treatment enhanced ROS in mycelia, which may be important in triggering sclerotial differentiation in P. umbellatus. Moreover, the application of antioxidants impaired ROS generation and inhibited sclerotial formation. Our findings may help to provide new insights into the biological mechanisms underlying sclerotial morphogenesis in P. umbellatus.

Identification of Hortaea werneckii Isolated from mangrove plant Aegiceras comiculatum based on morphology and rDNA sequences.

Hortaea werneckii is a black yeast-like ascomycetous fungi associated with the human superficial infection tinea nigra, which commonly occurs in tropical and subtropical countries. Now, this fungus has been found in the halophilic environment all over the world and recognized as a new model organism in exploring the mechanisms of salt tolerance in eukaryotes. During a survey of endophytic fungi of mangrove forest at South China Sea, two isolates of H. werneckii were recovered from medicinal plant of Aegiceras comiculatum. The isolates were identified by morphological characters and phylogenetic analyses (e.g., ITS rDNA, LSU rDNA and translation elongation factor EF1α). Some physiological tests such as thermotolerance, acid tolerance (pH) and NaCl tolerance as well as pathogenicity test in vitro for the strains of Hortaea were performed. It is the first report that H. werneckii was isolated from medicinal plant of A. comiculatum in south sea of China as the endophytic fungi.

Uncommon thyroglossal duct cyst with inward tendency: a recommendation regarding ingrowth type.

OBJECTIVE: There has been a growing number of case reports on uncommon thyroglossal duct cyst (TDC) extending into the oropharynx and/or laryngopharynx, which has often been misdiagnosed. We therefore examined the unfamiliar radiological and clinical characteristics of the cases in question so that we could advance the current store of knowledge. METHODS: From January 2005 to May 2009, all cases with TDC seen at a tertiary hospital, whose clinical data and images included CT and MRI, were included in this retrospective study. Cases with an uncommon thyroglossal duct cyst were chosen and divided to three different sub-types: intra-laryngeal, intra-lingual, and trans-laryngeal, according to the clinical syndrome and the sites of masses. RESULTS: In this study, 250 cases with TDC were collected, 21 (8.40%) of which presented extending images. Five such cases were of the intra-laryngeal type, with a mass lying close to the foramen cecum or posterior of the hyoid bone; 2 were classified as intra-lingual type, with a cyst in the tongue; 14 were classified as trans-laryngeal type, with a tumor occurring below the hyoid bone. CONCLUSION: Uncommon TDCs tend to extend into the range of the respiratory tract. This novel type of ingrowth could facilitate early correct diagnosis and the formulation of an appropriate treatment plan.

[Adsorption of heavy metal ions on two types of manganese oxides analyzed by AAS and AFS].

Two types of manganese oxides, the octahedral layer structure (OL) and the octahedral molecular tunnel structure (OMS), were controllably synthesized via a facilely hydrothermal route and used to remove heavy metal ions (Pb2+, Cu2+, Ni2+ , Hg2+) in solutions. The heavy metal ion concentrations before and after adsorption were determined by atomic absorption spectroscopy (AAS) and atomic fluorescence spectroscopy (AFS) to evaluate the material adsorption performance. The competitive adsorption of the four ions (Pb2+, Cu2+, Ni2+, Hg2+) on manganese oxides was also investigated. The results showed that OMS exhibited better adsorption ability than OL and had excellent adsorption selectivity to Pb2+, with 98% adsorption efficiency in two minutes. Therefore, this can be proposed as a simple, green and efficient method for treatment of polluted water.

[Proteome analysis on interaction between Anoectochilus roxburghii and Mycorrhizal fungus].

OBJECTIVE: To study the mechanism of plant growing promoted by Mycorrhizal fungus through the difference of proteomes. METHOD: The differential proteomes between uninoculated and inoculated endophytic fungi, Epulorhiza sp. on Anoectochilus roxburghii were analyzed by two-dimensional gel electrophoresis and MALDI-TOF/TOF mass spectrum. RESULT AND CONCLUSION: Twenty-seven protein spots were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Twenty-two candidate proteins were identified by database comparisons. The function of these proteins mostly involved in signal transduction, metabolic regulation, as well as photosynthesis and substance metabolism. The results indicate that the regulator control system of plant is influenced by fungi action, and the positive regulation improves substance metabolism and photosynthesis, which results in strong plant and higher resistance. It is also deduced that silent genes may exist in endosymbiosis plants.

Lingual thyroglossal duct cyst with recurrence after cystectomy or marsupialization under endoscopy: diagnosis and modified Sistrunk surgery.

OBJECTIVE: To explore the radiologic characteristics of lingual thyroglossal duct cyst relevant to diagnosis. In addition, to probe the feasibility of modified Sistrunk surgery for patients who experience recurrence after cystectomy or marsupialization under endoscopy. STUDY DESIGN: Retrospective. METHODS: Seven patients, three male and four female, who had been diagnosed with lingual thyroglossal duct cysts, had received cystectomy or marsupialization under endoscopy between one and eight times with cyst recurrence soon after every operation. All of these cases were evaluated by CT before proceeding with the latest modified Sistrunk surgery. During surgery, we routinely used methylene blue to trace the cysts, and then we used an enlarged Sistrunk procedure for such cases. RESULTS: The CT images demonstrated that there were cysts located posteriorly to the tongue that had a close relationship with the hyoid bone and the foramen cecum. In addition, the results of the pathological examinations were consistent with thyroglossal duct cysts. During the postoperative follow up of 18 to 31 months, the patients did not show any symptoms or signs of recurrence. The results of their most recent examinations, two by laryngoscopy and five by CT scan, did not reveal any abnormality in their pars laryngea pharyngis. CONCLUSIONS: CT could differentiate lingual thyroglossal duct cysts from the other cysts occurring at the lingual root. For those patients with lingual thyroglossal duct cysts that recur after cystectomy or marsupialization under endoscopy, the modified Sistrunk operation could be a suitable treatment option.