Comparative study of optical coherence tomograph and histological images of eustachian tube nasopharyngeal region and adjacent structures in vivo and ex-vivo miniature pigs.

OBJECTIVES: Optical Coherence Tomograph (OCT) imaging technology can be used to examine, in vivo, the human ET. At present, it is impossible to achieve the OCT scanning vivo and ex vivo in the same individual human body, or study the consistency between OCT images and histological images of the eustachian tube nasopharyngeal region and adjacent structures. The aim of this study was to determine the consistency between OCT images and histological sections in vivo and ex vivo in miniature pigs. METHODS: OCT imaging was performed on five adult miniature pigs in vivo and ex vivo. The images of the eustachian tube OCT (ET-OCT), nasopharynx OCT (NP-OCT) and histological cross sections were further studied. RESULTS: All five miniature pigs achieved the OCT scan successfully, acquiring ET-OCT and NP-OCT images in vivo and ex vivo on both sides. The acquired ET OCT images closely matched the histological images, revealing details of the cartilage, submucosa, glands, and mucosa. The lower segment of the ET wall mucosa had an abundance of glands and submucosal tissues, with more low-signal areas appearing in the ex vivo images. The NP-OCT images of the nasopharynx matched the details of the mucosa and submucosal tissues. The ex-vivo OCT images showed thicker mucosa and more scattered slightly lower signal areas compared to the vivo OCT images. CONCLUSIONS: ET-OCT images and NP-OCT images matched the histological structure of eustachian tube nasopharyngeal region structures in miniature pigs both in vivo and ex vivo. OCT images may be sensitive to changes in edema and ischemia status. There is a great potential for morphological assessment of inflammation, edema, injure, mucus gland status.

Autoimmune thyroiditis in patients with sudden sensorineural hearing loss.

Objective: This study aims to evaluate the association between autoimmune thyroiditis and Sudden Sensorineural Hearing Loss (SSNHL). Methods: Hundred and five patients with SSNHL were enrolled. Audiometric tests, serum thyroid autoantibodies (TPOAb, TgAb) were studied. Based on the thyroid autoantibody results, patients were divided into two groups: thyroid autoantibody-positive and negative. The relationship between thyroid autoimmunity and audiological characteristics was analyzed. Results: Twenty-six patients (24.8%) of the SSNHL had thyroid autoantibody elevated. The pure tone average (PTA) of patients with and without thyroid autoantibody is 60 ± 38.51 and 54.99 ± 33.87 dBHL, respectively. The PTA was significantly improved in both groups after treatment (p < 0.001), but the hearing gains were similar in both groups (p = 0.205). Hearing loss of 2000-8000 Hz was worse than 125-1000 Hz among thyroid autoantibody-positive patients (p < 0.05), but the hearing improvement of both groups have no significant difference. The hearing improvement of 125-1000 Hz is significantly better than 2000-8000 Hz among patients with thyroid autoantibody negative (p < 0.05). Conclusions: We speculate that a potential association between thyroid autoimmunity and SSNHL. Thyroid autoimmunity may be a pathogenesis factor of SSNHL and associated with more severe hearing loss of high-frequency hearing.

Application of Quantitative Susceptibility Mapping in the Assessment of Iron Content in Brain Regions of Normal Children.

PURPOSE: We evaluated brain iron content in a healthy pediatric population using quantitative susceptibility mapping (QSM). METHODS: From June 2018 to December 2019, healthy subjects aged 2-18 years old (200 males, 200 females) with no anatomical abnormalities were assessed. All of the children underwent 3D T1 anatomical MRIs in addition to the sequence scans of enhanced T2 star-weighted angiography (ESWAN). The ESWAN sequence images were obtained with software to attain quantitative susceptibility mapping of the entire brain. The magnetic susceptibility values in the same brain region were compared across different age groups. The magnetic susceptibility values expressed in the same age group were compared across sexes, brain sides, and brain regions. RESULTS: The magnetic susceptibility value of each brain region increased with age, and the magnetic susceptibility value expressed by each brain region demonstrated a positive correlation with the children's age (r=0.63, P<0.05). No dramatic difference in magnetic susceptibility was observed between the brain's left side and right side in the children within the age range ≥2-<6; however, among the children within the age range ≥6-<18, the magnetic susceptibility values expressed by the left putamen nucleus, globus pallidus, and substantia nigra were higher than those expressed by the same regions on the right side (P<0.05). CONCLUSION: Quantitative susceptibility mapping can be used to evaluate the content of iron in each brain region of normal children.

Quantitative susceptibility mapping shows lower brain iron content in children with attention-deficit hyperactivity disorder.

To investigate the feasibility of quantitative susceptibility mapping in children with attention-deficit hyperactivity disorder (ADHD), 53 children with ADHD aged 5-16 years were prospectively selected as the study group and 49 healthy children matched with age and gender were selected as the control group. All children underwent magnetic resonance imaging conventional sequence, 3D-T1, and enhanced T2*-weighted magnetic resonance angiography (ESWAN) sequence scanning. The iron content of brain regions was obtained through software postprocessing, and the iron content of brain regions of children with ADHD and healthy children was compared and analyzed to find out the characteristics of the iron content of brain regions of children with ADHD. The iron content in frontal lobe, globus pallidus, caudate nucleus, substantia nigra, putamen, and hippocampus of children with ADHD was lower than that of healthy children (p < .05). There was no significant difference in the content of iron in the left and right brain regions of children with ADHD (p > .05). The volume of frontal lobe and hippocampus of children with ADHD was lower than that of healthy children (p < .05). Iron content in brain areas such as globus pallidus, caudate nucleus, hippocampus, and putamen could distinguish children with ADHD (Area under curve [AUC] > 0.5, p < .05). Quantitative susceptibility mapping showed decreased iron content in some brain regions of children with ADHD.

[Effect of circ-SFMBT2 on the biological behavior of non-small cell lung cancer cells by targeting the miR-7-5p/ADAM10 axis].

OBJECTIVE: To explore the effect of circ-SFMBT2 on the biological behavior of non-small cell lung cancer (NSCLC) cells and its regulatory role on the miR-7-5p/ADAM10 axis. METHODS: qRT-PCR and Western blotting were used to determine the expression of circ-SFMBT2, miR-7-5p, and ADAM10 in NSCLC tissues and adjacent tissues. Pearson analysis was used to analyze the correlation between circ-SFMBT2 and miR-7-5p, and between miR-7-5p and ADAM10. In vitro cultured human bronchial epithelial-like cells (HBE) and lung cancer cell lines H1650, H460, A549, H1299. CCK-8 and EdU methods were used to assess the ability of cell proliferation. Plate experiment was used to detect the clone formation ability. Flow cytometry was used to detect the apoptosis rate. Transwell experiment was used to detect cell invasion ability. Dual luciferase reporter experiment detects the targeting relationship between circ-SFMBT2 and miR-7-5p, and between miR-7-5p and ADAM10. Transplanted tumor experiment in nude mice assessed the effect of knocking down circ-SFMBT2 on the growth of transplanted tumor. Immunohistochemical experiments were performed to detect the positive rates of ADAM10 and Ki67 proteins in transplanted tumor tissues. RESULTS: The expression levels of circ-SFMBT2 and ADAM10 were increased in NSCLC tissues and cell lines, while decreased the expression of miR-7-5p. circ-SFMBT2 was negatively correlated with miR-7-5p, while miR-7-5p was negatively correlated with ADAM10. Silencing the overexpression of circ-SFMBT2 and miR-7-5p could inhibit cell proliferation, clone formation and invasion, and also promote apoptosis. circ-SFMBT2 could target miR-7-5p, and ADAM10 was the target gene of miR-7-5p. The combined effect of silencing circ-SFMBT2 and inhibition of miR-7-5p, as well as miR-7-5p overexpression and ADAM10 overexpression could promote cell proliferation, clone formation and invasion, and also suppress cell apoptosis. Silencing circ-SFMBT2 could inhibit the growth of transplanted tumors. CONCLUSION: Silencing circ-SFMBT2 can suppress the proliferation, clone formation, invasion ability and induce apoptosis of NSCLC cells by regulating the miR-7-5p/ADAM10 axis.

Application of prospective ECG-gated multiphase scanning for coronary CT in children with different heart rates.

BACKGROUND: To investigate the application of prospective ECG-gated multiphase scanning in coronary CT imaging in children with different heart rates. METHODS: In the control group, 160 children aged 2-4 years who underwent a coronary CT examination in our hospital from May 2016 to December 2017 were retrospectively selected. They were divided into five subgroups according to their heart rate frequency: 75-85 beats/min, 86-95 beats/min, 96-105 beats/min, and 106-120 beats/min. There were 40 children in each subgroup. Each child was treated with retrospective ECG-gated scanning technology. Six groups of phase images were reconstructed: 40%, 45%, 50%, 70%, 75% and 80%. The optimal phase was selected for coronary artery reconstruction. In the study group, 240 children aged 2-4 years who underwent coronary artery CT examination in our hospital from January 2018 to May 2019 were prospectively selected and divided into five subgroups according to the heart rate frequency: 75-85 beats/min, 86-95 beats/min, 96-105 beats/min, and 106-120 beats/min. There were 60 children in each subgroup. A prospective ECG-gated multiphase scanning technique was used to reconstruct 70%, 75% and 80% phase images in the subgroups with heart rates < 85/min. In the remaining subgroups, 40%, 45% and 50% phase images were reconstructed, and the optimal phase was selected for coronary artery reconstruction. The scanning parameters, dosage of contrast medium and injection mode of contrast medium were the same in both groups. The radiation dose and image quality of the coronary artery were compared between the two groups at the same heart rate. RESULTS: When comparing the two groups at the same heart rate, the radiation dose in the study group was 72% lower than that in the control group (P < 0.05). There was no significant difference in coronary artery image quality between the two groups at the optimal phase (P > 0.05). CONCLUSIONS: Applying prospective ECG-gated multiphase scanning technology to children's coronary CT imaging can significantly reduce the scanning radiation dose without affecting the quality of the coronary artery image.

Investigations on the potential of optical coherence tomography as an imaging tool for eustachian tube.

The purpose of this study was to explore the feasibility of eustachian tube optical coherence tomography (ET-OCT) for imaging the pharyngeal region of the eustachian tube (ET). Ten subjects with ear complaints underwent ET-OCT guided by nasal endoscopy, and ET-OCT examination was performed on both sides of each subject's ETs. The process and resulting images were analysed. Ten subjects ranging from 21 to 73 years old (45 ± 14.77) were enrolled in this study. Eighteen ET-OCT imaging examinations were completed. The mean duration of each examination was 2.80 ± 1.62 min (ranging from 2 to 7 min). There were no adverse events or complications. In some subjects, the ET-OCT images clearly presented the microstructures of the ET wall, including the lumen, mucosa, submucosa, cartilage and plica. However, in some subjects, it showed different characteristics, such as an unclear hierarchy and secretions in the lumen. ET-OCT may help to distinguish the structural composition of the ET and elucidate related pathophysiological mechanisms. It is a valuable imaging tool suited for the ET, with potential diagnostic value in determining the morphology of the lumen, intraluminal mucosa and submucosal tissue in the pharyngeal region of the ET.

LINC00657 knockdown suppresses hepatocellular carcinoma progression by sponging miR-424 to regulate PD-L1 expression.

BACKGROUND: Hepatocellular carcinoma (HCC) is the sixth most commonly diagnosed malignant tumor and the fourth leading cause of cancer-related deaths worldwide. As a novel non-coding RNA, LINC00657 was firstly identified as an oncogenic role in breast cancer. However, few research focus on the effect of LINC00657 on the progression of HCC. OBJECTIVES: The purpose of this study was to investigate the effect of LINC00657 on HCC tissues and cells, and further explore the potential mechanism. METHODS: We first measured the expression of LINC00657 in HCC tissues and cell lines using qRT-PCR. Next we established LINC00657 knockdown in HCC cells. CCK-8 assay, cell invasion assay, flow cytometry analysis, qRT-PCR and western blotting were applied to assess the role of LINC00657 knockdown in the biological behavior of HCC cells. The bioinformatics analysis and the rescue experiment were devoted to the underlying mechanism. RESULTS: LINC00657 was remarkably overexpressed in HCC tissues and cell lines, associated with poor prognosis. LINC00657 knockdown repressed cell proliferation and invasion, promoted cell apoptosis of HCC cell lines. The bioinformatics analysis showed LINC00657 sponged miR-424 as a ceRNA. Besides, PD-L1 mimic rescued the suppression of si-LINC00657 in the biological behavior of HCC cells. CONCLUSION: In a word, we observed LINC00657 regulated PD-L1 expression by sponging miR-424, thus affecting the developments of hepatocellular carcinoma. These findings LINC00657 may provide new evidence for therapeutic application in hepatocellular carcinoma.

Application of multiple injections of contrast agent in head and neck CT arteriovenous angiography in children: Study protocol clinical trial (SPIRIT Compliant).

OBJECTIVE: To investigate the application value of multiple injections of contrast agent in head and neck CT arteriovenous angiography in children. METHODS: A total of 100 children aged 6 to 7 years who needed head and neck CT arteriovenous angiography were prospectively selected. They were randomly divided into a control group and a research group, with 50 children in each group. The same scanning parameters and reconstruction methods were used. The right median cubital vein was injected intravenously with the contrast agent Omnipaque (350 mg I/ml). For children in the control group, a bolus of undiluted contrast agent (dose was 2 ml/kg, upper limit was 50 ml) was injected 1 time. The arterial phase and vein phase of the head and neck vessels were scanned. For children in the research group, a contrast agent bolus diluted with saline to a concentration of 20% was first injected (dose was 1 ml/kg, upper limit was 25 ml), and then an undiluted contrast agent bolus (dose was 1 ml/kg, upper limit was 25 ml) was injected. Thresholds were used to trigger the scanning of the head and neck arterial phases. The CT image quality of the head and neck arteries and veins, radiation dose and contrast agent dose were compared between the 2 groups. RESULTS: Subjective evaluation of CT image quality of arteries: there were 47 cases of 4 points and 3 cases of 3 points in the control group and 34 cases of 4 points and 16 cases of 3 points in the research group. Subjective evaluation of CT image quality of veins: there were 47 cases of 4 points and 3 cases of 3 points in the control group and 5 cases of 4 points, 42 cases of 3 points and 3 cases of 2 points in the research group. The CT value of brain arterial vessel enhancement was higher in the control group than the research group, and the difference was statistically significant (P < .05). The CT value of vein enhancement was higher in the control group than the research group, and the difference was statistically significant (P < .05). The X-ray dose in the research group was 51% lower than that in the control group; the contrast agent dose in the research group was 44% lower than that in the control group. CONCLUSION: For the head and neck enhanced CT examination of children, the method of first bolus injection of 20% diluted contrast agent and later bolus injection of undiluted contrast agent can clearly demonstrate the head and neck arteries and veins one time, reducing the X-ray dose and contrast agent dose, which has clinical practical value in the enhanced CT examination of children with head and neck disease.

Construction and preliminary identification of a prokaryotic expression single-chain antibody fragments library against Streptococcus pneumoniae from antibody-producing cells in human tonsil.

Tonsillitis is the inflammation of the tonsils due to infection, many patients ultimately have to undergo tonsillectomy. In order to improve the accuracy of diagnosis and even create a new treatment for tonsillitis, we constructed a prokaryotic expression single-chain antibody fragment library against Streptococcus pneumoniae with immunoglobulin heavy chain variable region (VH), κ light chain (Vκ), and λ light chain (Vλ) genes by using human tonsil tissue. Plasmid DNA sequencing showed that single-chain antibodies were complete and constructed correctly. The binding activity of recombinant clones was detected by enzyme-linked immunosorbent assay (ELISA), results showed that the binding activity and specificity of anti-S. pneumoniae single-chain fragment variable (scfv) is proved to be successful. The single-chain antibody may be an attractive strategy for tonsillitis etiologic diagnosis and therapy.

Susceptibility and severity of cancer-related fatigue in colorectal cancer patients is associated with SLC6A4 gene single nucleotide polymorphism rs25531 A>G genotype.

PURPOSE: To explore the correlation between the SERT gene promoter single nucleotide polymorphisms (SNPs) rs25531 and rs956304 and the cancer-related fatigue (CRF) of colon and rectal cancer, and also to analyze the correlation of the interaction of genetic and non-genetic factors. METHOD: A sample of 568 colon and rectal cancer patients were recruited from the Second Affiliated Hospital of Nanchang University from October 2013 to December 2015. The Chinese version of the Brief Fatigue Inventory (BFI-C) was used to evaluate the CRF. The genomic DNA was extracted from peripheral blood samples of the patients. Direct sequencing was used to determine the rs25531 and rs956304 genotypes. RESULTS: Compared with the AA genotype, the risk of suffering from CRF and the severity of CRF increased to 1.77 times (95% CI = 1.22-2.59, P = 0.003) for patients who carry with G allele (AG+GG genotype) at rs25531 locus. CONCLUSIONS: The SERT gene promoter SNP rs25531 was associated with the CRF in patients with colon and rectal cancer and the G genotype was an independent risk factor for CRF among individuals with colon and rectal cancer in the study.

Treatment and Prognosis of Anaplastic Thyroid Carcinoma: A Clinical Study of 50 Cases.

INTRODUCTION: Although anaplastic thyroid carcinoma (ATC) is rare, it is one of the most aggressive human cancers. The optimal multimodal therapy policy of ATC is still debated, and a standardized treatment strategy remains to be established. This study aimed to evaluate the management aspect and prognosis of ATC. MATERIALS AND METHODS: The data were analyzed retrospectively for 50 patients with ATC to evaluate the clinical characters, management and factors influencing survival. Survival analysis was performed by Kaplan-Merier method and log-rank test, and multivariate analysis was performed using Cox proportional hazard model. RESULTS: The 1-year and 2-year overall survival rates (OS) were 48.0% and 26.0% respectively in all patients, with the 2-year OS of 40.0% and 31.0% and 6.3% for stage IVA, IVB and IVC respectively (P <0.05). In stage IVA and IVB patients, combined surgery with radiotherapy improved overall survival, and the 2-year OS were 50.0% and 35.7% respectively in the group with combined surgery with radiotherapy and the group with surgery with only (P <0.05). Postoperative radiotherapy improved local control rate in stage IVA and IVB patients (P <0.05). However, surgery, radiotherapy or chemotherapy could not improve the survival of stage IVC patients. Multivariate analysis showed that distant metastases, surgery, radiotherapy and tumor residue could predict the prognosis. CONCLUSION: Combined surgery and radiotherapy could improve overall survival in stage IVA and IVB patients. Patients with ATC have a bad prognosis. Distant metastases, surgery, radiotherapy and tumor residue are the most important factors affecting the prognosis.

HOXB7 as a promising molecular marker for metastasis in cancers: a meta-analysis.

Numerous studies on carcinoma have revealed that the expression level of HOXB7 in cancerous tissues was significantly higher than that in noncancerous tissues. Elevated expression of HOXB7 is associated with the susceptibility to lymph node metastasis and distant metastasis in various tumors. In this study, a meta-analysis was performed to involve majority of relevant articles and explore the association of HOXB7 expression level with metastasis in cancer patients. Literature retrieval was conducted by searching in a number of electronic databases (up to December 1, 2015). The meta-analysis was conducted with RevMan 5.3 software and Stata SE12.0. A total of 1,532 patients with carcinoma from 14 studies were included in analysis. The results of meta-analysis demonstrated that lymph node metastasis was observed more frequently in the patients group with high expression level of HOXB7 than in the patients group with low expression level of HOXB7 (odds ratio =2.17, 95% CI: 1.74-2.71, P<0.00001, fixed-effects model). In addition, a similar result was observed in the association between HOXB7 expression and distant metastasis; the odds ratio was 1.77 (95% CI: 1.09-2.88, P=0.02, fixed-effects model). This meta-analysis demonstrated that the overexpression of HOXB7 was significantly associated with metastasis in cancer patients, which may be served as a common molecular marker for indicating cancer metastasis.

Human metapneumovirus infection induces significant changes in small noncoding RNA expression in airway epithelial cells.

Small noncoding RNAs (sncRNAs), such as microRNAs (miRNA), virus-derived sncRNAs, and more recently identified tRNA-derived RNA fragments, are critical to posttranscriptional control of genes. Upon viral infection, host cells alter their sncRNA expression as a defense mechanism, while viruses can circumvent host defenses and promote their own propagation by affecting host cellular sncRNA expression or by expressing viral sncRNAs. Therefore, characterizing sncRNA profiles in response to viral infection is an important tool for understanding host-virus interaction, and for antiviral strategy development. Human metapneumovirus (hMPV), a recently identified pathogen, is a major cause of lower respiratory tract infections in infants and children. To investigate whether sncRNAs play a role in hMPV infection, we analyzed the changes in sncRNA profiles of airway epithelial cells in response to hMPV infection using ultrahigh-throughput sequencing. Of the cloned sncRNAs, miRNA was dominant in A549 cells, with the percentage of miRNA increasing in a time-dependent manner after the infection. In addition, several hMPV-derived sncRNAs and corresponding ribonucleases for their biogenesis were identified. hMPV M2-2 protein was revealed to be a key viral protein regulating miRNA expression. In summary, this study revealed several novel aspects of hMPV-mediated sncRNA expression, providing a new perspective on hMPV-host interactions.

Human metapneumovirus M2-2 protein inhibits innate immune response in monocyte-derived dendritic cells.

Human metapneumovirus (hMPV) is a leading cause of lower respiratory infection in young children, the elderly and immunocompromised patients. Repeated hMPV infections occur throughout life. However, immune evasion mechanisms of hMPV infection are largely unknown. Recently, our group has demonstrated that hMPV M2-2 protein, an important virulence factor, contributes to immune evasion in airway epithelial cells by targeting the mitochondrial antiviral-signaling protein (MAVS). Whether M2-2 regulates the innate immunity in human dendritic cells (DC), an important family of immune cells controlling antigen presenting, is currently unknown. We found that human DC infected with a virus lacking M2-2 protein expression (rhMPV-ΔM2-2) produced higher levels of cytokines, chemokines and IFNs, compared to cells infected with wild-type virus (rhMPV-WT), suggesting that M2-2 protein inhibits innate immunity in human DC. In parallel, we found that myeloid differentiation primary response gene 88 (MyD88), an essential adaptor for Toll-like receptors (TLRs), plays a critical role in inducing immune response of human DC, as downregulation of MyD88 by siRNA blocked the induction of immune regulatory molecules by hMPV. Since M2-2 is a cytoplasmic protein, we investigated whether M2-2 interferes with MyD88-mediated antiviral signaling. We found that indeed M2-2 protein associated with MyD88 and inhibited MyD88-dependent gene transcription. In this study, we also identified the domains of M2-2 responsible for its immune inhibitory function in human DC. In summary, our results demonstrate that M2-2 contributes to hMPV immune evasion by inhibiting MyD88-dependent cellular responses in human DC.

Different therapeutic strategies in primary salivary gland-type nasopharyngeal carcinomas.

PURPOSE OF REVIEW: Primary salivary gland-type nasopharyngeal carcinoma (PSGT-NPC) is an uncommon malignancy with aggressive behavior and poor prognosis. Its optimal treatment policy remains debated, even though recent evidence provides support for a multimodality approach. The aim of this study was to summarize the optimal management approaches and treatment outcomes of PSGT-NPCs. RECENT FINDINGS: As most of the PSGT-NPCs, such as adenoid cystic carcinoma, mucoepidermoid carcinoma and low-grade (well-differentiated) adenocarcinoma, have low sensitivity to radiation, combined surgical treatment and radiotherapy are still the main treatment approach for limited or resectable lesions. As a result of the fact that in well-differentiated PSGT-NPCs the occult neck metastasis rate is low (less than 20%), elective neck dissection is not recommended in patients with a node-negative neck. Since high-grade (poorly-differentiated) PSGT-NPCs are relatively sensitive to radiation, radiotherapy or chemoradiotherapy is currently considered as the main treatment policy for such patients. There is no evidence to indicate that chemotherapy would improve overall survival. Cranial nerve infiltration, residual tumor, and distant metastases are independent predictive factors of overall survival. SUMMARY: In most patients with PSGT-NPCs, especially for well-differentiated tumors, combined surgical treatment and radiotherapy should be recommended. For poorly-differentiated or unresectable tumors, radiotherapy or chemoradiotherapy is still considered the main treatment approach. Because of the rare incidence of PSGT-NPCs, the number of cases available for analysis is relatively small, and large multicentric studies should be conducted to further evaluate their optimal treatment policy.

Elective neck dissection in clinical stage I squamous cell carcinoma of the tongue: Does it improve regional control or survival time?

The objective of this study was to evaluate whether elective neck dissection could improve regional control or survival time in clinical stage I squamous cell carcinoma of the oral tongue (OTSCC). This was a retrospective study of patients with surgical treatment between January 1991 and December 2003. A total of 131 patients were included in the study, and all of them received operation of the primary site, while 88 cases underwent selective neck dissection simultaneously including level I-III neck dissection in 49 patients and level I-V neck dissection in 39 patients. In all these cases, the rate of occult neck metastases was 23.7%. The 4-year local control rates in patients with only primary site treatment, patients with level I-III neck dissection and patients with level I-V neck dissection were 81.0%, 83.6% and 89.1%, respectively. By univariate analyse, neck dissection did not increase regional control rate, disease free survival (DFS) or overall survival (OS). Multivariate analyses showed that neck dissection was not an independent factor for DFS or OS. This study showed that the occult neck metastases rate was 23.7% in clinical stage I OTSCC. Elective neck dissection did not significantly improve regional control, DFS and OS in clinical stage I patients. There is a need for accurate and valid methods to select the patients who would benefit from elective neck treatment.

Primary salivary gland type carcinoma of the nasopharynx: therapeutic outcomes and prognostic factors.

BACKGROUND: Primary salivary gland type nasopharyngeal carcinoma (SNPC) is a rare malignancy with diverse clinical behavior and different prognoses. Previous studies have reported on limited patient populations, and few long-term studies have outlined outcomes and prognostic factors. Furthermore, controversy exists as to the treatment policy of SNPC. The aim of this study was to define management approaches, therapeutic outcomes, and prognostic factors of SNPC. METHODS: The medical records of 67 patients with SNPC at 1 institution between 1977 and 2005 were reviewed. Patient records were analyzed for management approaches, outcomes, and prognostic factors. RESULTS: SNPC is a rare malignancy accounting for only 0.29% of nasopharyngeal malignancies, and the lymphatic metastases and distant metastases rates were 28.4% and 23.9%, respectively. The 5-year disease-free survival (DFS) and overall survival (OS) rates were 41.1% and 57.1%, respectively; no significant differences were found in DFS or OS between different histological subtypes. A significant difference was found in OS between surgical treatment and nonsurgical treatment in T1-T2 patients with well-differentiated tumors. Multivariate analyses indicated that lymph node metastases, stage, and distant metastases were independent factors for DFS, whereas cranial nerve invasion, tumor residue, and distant metastases were independent factors affecting OS. CONCLUSIONS: SNPC is a malignancy with generally favorable prognosis. In T1-T2 patients with well-differentiated tumors, SNPC should be treated by combined surgical operation and radiotherapy. Cranial nerve invasion, tumor residue, and distant metastases were independent factors affecting OS.

[Reconstruction and analysis of three-dimensional finite element model of human middle ear].

OBJECTIVE: To reconstruct a finite element model of human middle ear and measure characteristic dimensions of this model and calculate the mass properties of the ossicles. METHODS: The proposed method starts with the histologic section preparation of human temporal bone. Through tracing outlines of the middle ear components on the sections in AutoCAD2005, a set of exterior contours of the components is obtained. The three-dimensional solid model of middle ear, including tympanic membrane, ossicular bones, middle ear suspensory ligaments/muscles, are reconstructed using these contours in Unigraphics (UG). To prepare for finite element analysis (FEA) of the middle ear, all surfaces of the solid model are translated into ADINA, a commercial FE model package. Based on these surfaces, FE meshes of the middle ear are created, and material properties and boundaries are set up. The characteristic dimensions of this model are measured and the mass properties of the ossicles are calculated to confirm the accuracy of the geometric model constructed following the proposed method. RESULTS: The three-dimensional finite element model of the human middle ear that included tympanic membrane, ossicular bones and middle ear suspensory ligaments/muscles was reconstructed. The accuracy of this geometric model was confirmed with the outcome of the characteristic dimensions of this model and the mass properties of the ossicles. CONCLUSIONS: The proposed method not only provides an effective, convenient, economic, accurate way to reconstruct the three dimensional finite element model of human middle, but also provides a detailed knowledge of middle ear geometry that is required for finite element analysis.

[Establishment of mechanical middle ear model and the study of the acoustic characteristics of different ossicular prostheses].

OBJECTIVE: To design a tool for evaluating the sound transmission function of ossicular prosthesis and explore the impacts of ossicular prosthesis bead area and the effects of the mass of ossicular prosthesis on the sound transmission function in mechanical middle ear model. METHODS: Two latex membranes were used to represent the tympanic membrane and oval window membrane. The ossicular prosthesis was fitted between the artificial tympanic membrane and oval window membrane during the test. Pure tune signals were used to stimulate the vibration of tympanic membrane. The vibration of oval window membrane was recorded by a laser Doppler vibrometer. The ossicular transmission function was evaluated by comparing the vibration velocities of oval window membrane. Two groups of titanium ossicular prosthesis with different head area and mass respectively were fitted into a mechanical middle ear model to evaluate their sound transmission functions. RESULTS: The feeling threshold curve of mechanical middle ear model (MMEM) was similar to the hearing threshold curve of normal person. The transmission function of the prosthesis with small head area was better than that of prostheses with large head area at frequencies 1500-4000 Hz. The small-massed prostheses functioned better at higher frequencies and the large-massed prostheses functioned better at lower frequencies. But small-massed prostheses functioned better as a whole. CONCLUSIONS: The MMEM was an idea tool to evaluate the transmission functions of different ossicular prostheses. Both the head area and prosthesis mass had an influence on the transmission function of ossicular prosthesis. So while designing the ossicular prosthesis or performing ossiculoplasty, both the head area and prosthesis mass should he taken into consideration.