Investigations on the complex flows induced by dual-swept/dual-ramp wedges in supersonic flows.

The caret inlet with a dual-swept/dual-ramp configuration has excellent stealth performance and aerodynamic capability. Most previous investigations on this configuration have focused on experiments and numerical simulations but there are relatively few theoretical investigations. In this study, the flow field characteristics of dual-swept/dual-ramp configuration are investigated analytically and numerically. An analytical approach that combines the shock dynamics with a "spatial dimension reduction" was used to analyze the characteristics of the wave structures and state parameters of the flow field. The effects of the sweep angles and inflow Mach number on the flow field characteristics are investigated. The results indicate that the problem of shock/shock interaction in two intersecting wedges of large back-swept angle is a problem of weak shock interaction. Therefore, the theory of weak shock interaction is used to investigate the flow field characteristics, including the uniformity of the flow field and the total pressure recovery performance.

Linc-ROR promotes endometrial cell proliferation by activating the PI3K-Akt pathway.

OBJECTIVE: To observe the expressions of Linc-ROR and proteins in the PI3K-Akt pathway in an ectopic lesion of adenomyosis. PATIENTS AND METHODS: The expression of Linc-ROR in the ectopic endometrium, eutopic endometrium, and normal endometrium of adenomyosis was detected by qRT-PCR. Western blot was used to detect the protein expressions of PI3K-Akt in endometriosis and lesion endometriosis. Cell counting kit-8 (CCK-8) assay was utilized to detect cell proliferative activity. After interfering or overexpressing Linc-ROR, protein expressions of the PI3K-Akt pathway were detected by Western blot. RESULTS: Linc-ROR expression in the ectopic endometrium of adenomyosis was higher than that in the eutopic endometrium and normal endometrium, and the expression level of PTEN in adenomyosis tissues was decreased, whilst expression levels of Akt, p-Akt, p-PTEN were increased. Clinical data of enrolled patients indicated that there was a relationship between Linc-ROR expression and the type and severity of dysmenorrhea of adenomyosis. However, no relationship was observed between Linc-ROR expression and age, cesarean section, uterine surgery, and menstrual cycle. Cell counting kit-8 (CCK-8) assay showed that the proliferative activity of cells was significantly decreased after knockdown of Linc-ROR in the adenomyosis cells. Western blot revealed that the expression level of PTEN increased but the expression levels of p-Akt, p-PTEN and p-PDK1 decreased. Overexpression of Linc-ROR obtained the opposite results. CONCLUSIONS: Linc-ROR is highly expressed in the ectopic endometrium of adenomyosis, and it can promote the proliferative activity of endometrial cells by activating the PI3K-Akt pathway.

Genetic analysis of surgical margins in oral cavity cancer.

BACKGROUND: A histological, tumour-free surgical margin does not guarantee recurrence-free survival in patients with cancer. This study investigated the association between microsatellite alteration in tumour-free surgical margins and local recurrence in patients with oral cavity squamous cell carcinoma. METHODS: Patients with histologically confirmed oral cavity squamous cell carcinoma were enrolled in this prospective study. Cancerous specimens, corresponding surgical margins and peripheral blood were obtained. Microsatellite alteration was investigated using six dinucleotide microsatellite markers. All samples were amplified by PCR, followed by automatic fragment analysis. RESULTS: Microsatellite alteration was identified in 100 specimens (69·0 per cent) from 145 patients. Among them, 85 specimens carried loss of heterozygosity, whereas 55 had microsatellite instability (MSI). Patients with MSI at the surgical margin had a higher risk of local recurrence on multivariable analysis (odds ratio 7·17, 95 per cent c.i. 3·49 to 14·73). CONCLUSION: Molecular assessment of surgical margins can help identify patients at risk of local recurrence.

A prospective randomised trial of LigaSure Small Jaw® versus conventional neck dissection in head and neck cancer patients.

OBJECTIVES: We compared the differences between LigaSure Small Jaw®-assisted and conventional neck dissection in patients with head and neck cancer. DESIGN: Prospective randomised study. SETTING: Tertiary referral hospital. PARTICIPANTS: Patients scheduled to undergo neck dissection due to head and neck cancer were eligible for this study. The study group was treated using the LigaSure vessel sealing system (Small Jaw®; Covidien, Colorado, USA) for dissection and hemostasis throughout the whole procedures (ClinicalTrials.gov number: NCT02597582). MAIN OUTCOMES MEASURES: Operation duration, perioperative blood loss, postoperative drainage amount and postoperative pain status. RESULTS: The study group consisted of 21 patients, while the control group had 20 patients. The operation duration was shorter (97.1 versus 116.3 min, P = 0.022) and the average amount of injected analgesics was lower (8.8 versus 17.7 ampules, P = 0.037) in the study group. CONCLUSIONS: The assistance of the LigaSure Small Jaw® during functional neck dissection shortened the operation duration and decreased the amount of injected analgesics needed.

Clinical significance of changes of expression of the Wnt/ß-catenin signaling pathway in renal clear cell carcinoma.

OBJECTIVE: To explore the changes and clinical significance of expression of ß-catenin in renal carcinoma. PATIENTS AND METHODS: We selected 46 patients with renal clear cell carcinoma who were hospitalized from May 2013 to March 2016 and healthy adults (controls) matched for age and body weight, who were hospitalized in the physical examination center of our hospital during the same period. Peripheral blood of patients and controls was drawn for ELISA. After surgery, renal carcinoma and normal peritumoral tissue samples were harvested for immunohistochemical staining, Western blot analysis and qRT-PCR was used to observe changes of ß-catenin expression in renal carcinoma tissues. RESULTS: Compared with controls, ELISA showed that there were significant differences in ß-catenin levels in peripheral blood of patients with renal carcinoma (p<0.05). Western blot and qRT-PCR showed that the expression levels of ß-catenin in renal carcinoma tissues were higher than in normal peritumoral tissues and the differences were statistically significant (p<0.05). Immunohistochemical staining showed that ß-catenin was increased significantly in renal carcinoma tissue compared with normal peritumoral tissues (p<0.05). CONCLUSIONS: ß-catenin expression was significantly increased in the tumor tissues of patients with renal carcinoma. The measurement of ß-catenin expression levels in peripheral blood from patients could be used for early diagnosis of renal carcinoma, which is of great clinical significance.

Association between XRCC1 Arg280His polymorphism and risk of hepatocellular carcinoma: a systematic review and meta-analysis.

Hepatocellular carcinoma (HCC) is one of the most life-threatening malignancies worldwide. Defects in DNA repair genes may increase the risk of HCC. X-ray cross-complementing group 1 gene (XRCC1) is a major DNA repair gene involved in base excision re-pair. Recently, several studies have indicated that an association exists between XRCC1 polymorphism and HCC, particularly the Arg280His polymorphism. However, the data is inconsistent and incomplete. In this study, we conducted a meta-analysis to investigate the association between the XRCC1 Arg280His polymorphism and HCC risk. A total of 10 case-control studies included 1848 HCC cases and 1969 controls were examined in this analysis. Our results suggest that variant geno-types of the XRCC1 Arg280His gene are associated with a significantly increased risk of HCC in homozygote comparison (HisHis vs ArgArg, odds ratio, 1.55, 95% confidence interval, 1.10-2.18, P = 0.013); no het-erogeneity was observed (I2 = 0%). Our analysis suggests that the XRCC1 Arg280His polymorphism is associated with a higher risk of HCC.

Airway pH monitoring in patients with suspected obstructive sleep apnoea using the Dx-pH oropharyngeal probe: preliminary report of a prospective cohort study.

OBJECTIVES: To investigate the laryngopharyngeal reflux (LPR) episodes and pH values in patients with suspected obstructive sleep apnoea (OSA) using the Dx-pH oropharyngeal probe. DESIGN: Prospective cohort study. SETTING: Tertiary medical centre. PARTICIPANTS: Forty patients with complaint of snoring or suspected OSA were prospectively enrolled to receive full nocturnal polysomnography (PSG). The patients were divided into 2 groups: a simple snorers group if the Respiratory Disturbance Index (RDI) was < 5 and an OSA group if the RDI was ≥ 5. MAIN OUTCOME MEASURES: The patients simultaneously received Dx-pH oropharyngeal probe monitoring for 12 h from about 6 pm to 6 am of the next day. The number of LPR events was recorded if the nadir of rapid pH drops was below pH 5.0 and 5.5. The difference of LPR events between the two groups and the difference of LPR events between awake and sleep periods in each group were analysed, respectively. RESULTS: There were 18 (45%) patients diagnosed as OSA with a mean RDI of 28.7, and 22 patients (55%) diagnosed as simple snorers. Between 2 groups, there were no significant differences in the LPR events and pH values during the awake period, sleep period or overall recording period. Comparison of the LPR events and minimum pH values between the awake period and the sleep period revealed there were no significant differences in either group. CONCLUSION: Using the new sensitive Dx-pH oropharyngeal probe with PSG, we found that OSA does not correlate with a higher incidence of LPR episodes.

Preoperative blood sugar and C-reactive protein associated with persistent discharge after incision and drainage for patients with deep neck abscesses.

OBJECTIVES: The aim of this study was to investigate whether preoperative C-reactive protein (CRP) and blood sugar correlated with persistent discharge after incision and drainage for patients with deep neck abscesses. STUDY DESIGN: Retrospective data analysis. SETTING: Tertiary referral centre. PARTICIPANTS: A total of 204 patients who underwent operation for deep neck abscess. MAIN OUTCOME MEASURES: Persistent discharge after operation. RESULTS: One hundred seventy patients were included for final analyses. Most of the patients were male (n = 115; 68%) and the average age was 54 years. Using logistic regression analyses, age >55 years [odds ratio (OR): 3.053; P = 0.002], preoperative CRP >15 mg/dL (OR: 2.174; P = 0.027), and preoperative blood sugar >8.3 mmol/L (OR: 3.280; P = 0.001) were independent factors correlated with persistent discharge. CONCLUSIONS: Older age, elevated preoperative CRP level and blood sugar had a statistically significant association with persistent discharge after operation in deep neck abscesses patients.

Preliminary report of associated factors in wound infection after major head and neck neoplasm operations--does the duration of prophylactic antibiotic matter?

The aim of this study was to investigate whether an extended course of prophylactic antibiotic could reduce the wound infection rate in a subtropical country. Fifty-three consecutive cases scheduled to receive major head and neck operations were randomised into one-day or three-day prophylactic antibiotic groups. Thirteen cases (24.5 per cent) developed wound infections after operations. The duration of prophylactic antibiotic was not related to the surgical wound infection. However, pre-operative haemoglobulin less than 10.5 g/dl (odds ratio: 7.24, 95 per cent confidence interval: 1.28-41.0) and reconstruction with a free flap or pectoris major myocutaneous flap during the operation (odds ratio: 11.04, 95 per cent confidence interval: 1.17-104.7) were associated factors significantly influencing post-operative wound infection. Therefore, one day of prophylactic antibiotic was effective in major head and neck procedures but should not be substituted for proper aseptic and meticulous surgical techniques.

Studies on epoxy compound fixation.

Bioprostheses derived from collagenous tissues have to be fixed and subsequently sterilized before they can be implanted in humans. Clinically, the most commonly used fixative is glutaraldehyde. However, the tendency for glutaraldehyde to markedly alter tissue stiffness and promote tissue calcification are well-recognized drawbacks of this fixative. To address the deficiencies with the glutaraldehyde-fixed tissue, a new fixative, epoxy compound, was used to fix biological prostheses. The study was undertaken to investigate the fixation rates and crosslinking densities of biological tissues fixed with various epoxy compounds. These epoxy compounds are different in their chemical structures. Glutaraldehyde was used as a control. The fixation rates and crosslinking densities of the fixed tissues were determined by measuring their fixation indices and denaturation temperatures, respectively. Generally, the epoxy-fixed tissues were more pliable than the glutaraldehyde-fixed one. Furthermore, the tissues fixed with monofunctional epoxy compound were more pliable than those fixed with multifunctional epoxy compounds. With increasing pH or temperature, the fixation rate of epoxy compound increased. However, the number of epoxide functional groups did not seem to affect the fixation rate of the epoxy compound. The fixation rate of glutaraldehyde was faster than that of epoxy compounds. Additionally, the crosslinking density of the glutaraldehyde-fixed tissue was greater than that of the epoxy-fixed counterparts. Moreover, it was noted that the denaturation temperatures of the tissues fixed with glutaraldehyde or multifunctional epoxy compounds were significantly higher than the fresh ones (p < 0.05), while that fixed with monofunctional epoxy compound stayed roughly the same throughout the entire fixation process (p > 0.05). The results obtained in this study may be used to optimize the fixation process for developing bioprostheses fixed with epoxy compounds.