Surgical treatment of nasopharyngeal cancer - a consensus recommendation from two Chinese associations

BACKGROUND

Surgical treatment is playing an increasingly important role in the management of nasopharyngeal carcinoma (NPC). This consensus focuses on the indications for optimal surgery, and surgical methods in the whole process of treatment for NPC to provide a useful reference to assist these difficult clinical decisions.

METHODOLOGY

A thorough review of available literature on NPC and surgery was conducted by the Association for the prevention and treatment of nasopharyngeal carcinoma in China, international exchange and promotion Association for medicine and healthcare, and the Committee on nasopharyngeal cancer of Guangdong provincial anticancer association. A set of questions and a preliminary draft guideline was circulated to a panel of 1096 experienced specialists on this disease for voting on controversial areas and comments. A refined second proposal, based on a summary of the initial voting and different opinions expressed, was recirculated to the experts in two authoritative medical science and technology academic groups in the prevention and treatment of NPC in China for review and reconsideration.

RESULTS

The initial round of questions showed variations in clinical practice even among similar specialists, reflecting the lack of high-quality supporting data and resulting difficulties in formulating clinical decisions. Through exchange of comments and iterative revisions, recommendations with high-to-moderate agreement were formulated on general treatment strategies and details of surgery, including indications and surgical approaches.

CONCLUSION

By standardizing the surgical indications and practice, we hope not only to improve the surgical outcomes, but also to highlight the key directions of future clinical research in the surgical management of NPC.

[The efficacy and safety of standardized dust mite allergen subcutaneous immunotherapy in children with allergic rhinitis during treatment]

Objective: To evaluate the efficacy and safety of standardized dust mite allergen subcutaneous immunotherapy (SCIT) in children with allergic rhinitis (AR) during treatment. Methods: A total of 283 children with AR diagnosed with definite dust mite allergy and completed 2 to 3 years of SCIT who attended the Department of Otorhinolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, from August 2019 to October 2021 were included, including 205 males and 78 females, with a mean age of 10.8 years. The total nasal symptoms score (TNSS), symptom medication score (SMS), rhinoconjunctivitis quality of life questionnaire (RQLQ) and visual analogue scale (VAS) before and after 2 to 3 years' treatment were recorded, and the differences before and after treatment were compared. Adverse reactions during SCIT were recorded to evaluate its safety. SPSS 22.0 software was used for statistical analysis. Results: The overall effectiveness rate during SCIT in 283 children with AR was 89.4% (253/283). Compared with baseline, all symptom scores, medication scores and quality of life scores were significantly lower after 2 to 3 years of SCIT (all P<0.05). Further group comparisons showed positive efficacy in patients with different clinical characteristics, including age, gender, smoking status, family history of AR, symptom severity, mono-or poly-allergy, and second immunization, with no statistically significant differences between groups (all P>0.05). A total of 12 735 injections were administered during the SCIT, and a total of 213 (1.67%) injections of local adverse reactions occurred, mainly in the initial treatment phase, and the diameter of the local air mass was mostly 5 to 20 mm; 71 (0.56%) injections of systemic adverse reactions occurred, mainly in the initial treatment phase, and most of them were grade 1 reactions with no serious systemic adverse reaction such as shock. Conclusion: Standardized dust mite SCIT has a good safety profile and definite efficacy in treating AR children with different clinical characteristics. It can significantly improve all symptoms, reduce the use of symptomatic drugs and improve their quality of life.

[Impact of asthma action plan-based remote joint management model on asthma control in children]

Objective: To compare the effects of the China Children's Asthma Action Plan (CCAAP)-based remote joint management model with traditional management model on the control of childhood asthma. Methods: A retrospective cohort study was conducted to analyze the general data and asthma control assessment data of 219 children with asthma who attended the respiratory department of Guangzhou Women's and Children's Medical Center from April 2021 to October 2021 and were followed up for 1 year or more. According to the follow-up management model, the CCAAP-based remote joint management model was used in the observation group and the traditional management model was used in the control group, and the propensity score matching method was applied to match the data of children in the two management models for comparison. Paired-samples t-test, Wilcoxon signed-rank test, McNemar χ2-test or χ2-test or nonparametric tests were used to compare the general data and asthma control assessment data between the two matched groups of children. Results: Among 219 children with asthma, 145 were male and 74 were female, aged at consultation (7.2±2.4) years. There were 147 cases in the observation group and 72 cases in the control group, and 27 cases in each of the observation and control groups were successfully matched. The number of asthma exacerbation aura, acute exacerbations, and emergency room visits or hospitalizations for asthma exacerbations were lower in the observation group than in the control group after pairing (1 (0, 2) vs. 3 (1, 5) times, 0 (0,0) vs. 0 (0, 1) times, 0 (0,0) vs. 1 (0, 1) times, Z=-3.42, -2.58, -3.17, all P<0.05). The use of peak flowmeters was higher in children aged 5 years and older in the observation group than in the control group after pairing (100% (22/22) vs. 13% (3/23), χ2=54.00,P<0.001). The ratio of actual to predicted 1st second expiratory volume of force after follow-up in the observation group after pairing was higher than that before follow-up in the observation group and after follow-up in the control group ((95±11)% vs. (85±10)%, (95±11)% vs. (88±11)%, t=-3.40, 2.25, all P<0.05). The rate of complete asthma control after follow-up was higher in both the observation and control groups after pairing than before follow-up for 12 months in both groups (93% (25/27) vs. 41% (11/27), 52% (14/27) vs. 41% (11/27), H=56.19, 45.37, both P<0.001), and the rate of complete control of asthma in children in the observation group was higher than that in the control group at 3 and 12 months of follow-up management (56% (15/27) vs. 25% (5/20), 93% (25/27) vs. 52% (14/27), χ2=47.00, 54.00, both P<0.001). The number of offline follow-up visits, inhaled hormone medication adherence scores, and caregiver's asthma perception questionnaire scores were higher in the observation group than in the control group after pairing (6 (4, 8) vs. 4 (2,5), (4.8±0.3) vs. (4.0±0.6) score, (19.3±2.6) vs. (15.2±2.7) score, Z=6.58, t=6.57, 5.61, all P<0.05), and the children in the observation group had lower school absences, caregiver absences, asthma attack visit costs, and caregiver PTSD scores than the control group (0 (0,0) vs.3 (0, 15) d, 0 (0,0) vs. 3 (0, 10) d, 1 100 (0, 3 700) vs. 5 000 (1 000, 10 000) yuan, 1.3 (1.1, 1.9) vs. 2.0 (1.2, 2.7) score, Z=-2.89, -2.30, 2.74, 2.73, all P<0.05). Conclusion: The CCAAP-based joint management model of asthma control is superior to the traditional management model in the following aspects: it can effectively improve asthma control, self-monitoring, and lung function in children; it can improve treatment adherence and caregivers' asthma awareness; and it can reduce the duration of absenteeism from school, the cost of asthma exacerbation visits, and caregiver's negative psychology.

[Incidence and prognosis of olfactory and gustatory dysfunctions related to infection of SARS-CoV-2 Omicron strain: a national multi-center survey of 35 566 population]

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.

[Application of temporalis muscle flap in repair and reconstruction after the resection of tumor or necrotic foci following radiotherapy of nasopharyngeal carcinoma]

Objective: To summarize and popularize the application of temporalis muscle flap in repair and reconstruction after the resection of tumor or necrotic foci following radiotherapy of nasopharyngeal carcinoma (NPC). Methods: A retrospective analysis was made on the patients treated in the Department of Otorhinolaryngology Head and Neck Surgery of Xiangya Hospital between January 2019 and March 2021 who underwent surgical resection of tumor or necrosis of NPC after radiotherapy and temporalis muscle flap repair. The effect of the repair and the patients' postoperative conditions were analyzed. Results: A total 29 patients, 19 males and 10 females, aged from 33 to 65 years old, were included in the study, and were followed up for 6-35 months. Except for 2 patients who were not followed due to bleeding or special bacterial infection, the others' temporalis muscle flap healed well and no cerebrospinal fluid rhinorrhea or massive hemorrhage occurred. After the operation, all patients had no nasopharyngeal reflux or new open rhinolalia, and in some patients, the open rhinolalia even got relieved. Except for one case of depressed temporal fossa caused by infection and followed debridement and another one case of shallowed forehead wrinkles, the appearances of the other patients were basically symmetrical. Some patients had temporary mouth opening limitation after operation, and all of them recovered after rehabilitation exercises. Conclusions: The temporalis muscle flap can protect the skull base and internal carotid artery, and improve the quality of life of patients after the resection of NPC or necrotic foci. It is a reliable pedicled flap for repairing skull base defect with simple operation procedures and relatively few complications.

[Establishment and analysis of prediction model for invasive subsolid pulmonary nodules based on radiomics]

Objective: To evaluate the best radiomic features based prediction model for identifying the histopathological subtypes of invasive adenocarcinoma or noninvasive pulmonary nodules appearing as subsolid nodules. Methods: A total of 352 patients (108 males and 244 females, median age was [M(Q₁,Q₃)]57 (50,65), underwent high-resolution chest CT and appearing as subsolid nodules and further treated by surgical resection whose subsequently pathological results were classified as atypical adenomatous hyperplasia (AAH), carcinoma in situ (AIS), microinvasive carcinoma (MIA), invasive adenocarcinoma (IA), from January 2015 to September 2019, in Radiology Department of Zhongda Hospital Affiliated to Southeast University and Jinling Hospital, Medical School of Nanjing University were retrospectively collected. They were divided into non-invasive group (n=233) and invasive group (n=119) according to pathological findings. According to the ratio of training set: internal test set: external test set, which is about 3∶1∶1,the patients in Zhongda Hospital Affiliated to Southeast University were randomly divided into training set (n=215, non-IA∶IA 155∶60) and internal test set(n=69, non-IA∶IA 52∶17), meanwhile a certain number of patients in Jinling Hospital, Medical School of Nanjing University(n=68, non-IA∶IA 26∶42)were randomly selected as an independent external test set. Particular quantitative parameters of the nodules, radiomic features, morphological characteristics, clinical data, and serum tumor markers were recorded. Radiomic label was constructed using LASSO regression method. The morphological model, CT model and comprehensive model were constructed by binary logistic regression and were verified in test sets, respectively. Results: Shape_MinorAxis(Gradient),Glszm_ZoneEntropy(LBP) were selected as the two most significant features based on training set. Radiomic tag=1.065 75×Shape_MinorAxis(Gradient)+0.030 58×Glszm_ZoneEntropy(LBP). Comparing the prediction performance of all models in each data cohort, the CT model (Ln(P/1-P)=-2.417 11+1.031 60×Radimic tag+1.203 06×Diameter+1.614 21×(Pleural indentation sign = Y) constructed by radiomic label, pleural depression, and quantitative parameters (diameter, average density) was much better than other models and was chosen as the optimal model, with an AUC of CT models in training cohort and test cohort was 0.954 (95%CI: 0.927-0.981), 0.865 (95%CI:0.764-0.966), better than morphological model 0.857 (95%CI:0.796-0.918), 0.818(95%CI: 0.686-0.949) and comprehensive model 0.951(95%CI: 0.921-0.981), 0.856(95%CI: 0.730-0.982), respectively. Conclusion: The integrative CT model has a better prediction efficiency for identifying invasive or noninvasive nodules appearing as subsolid nodules.

Radiosensitizer EXO-miR-197-3p Inhibits Nasopharyngeal Carcinoma Progression and Radioresistance by Regulating the AKT/mTOR Axis and HSPA5-mediated Autophagy

The biological functions of exosomes and microRNAs (miRs) in nasopharyngeal carcinoma (NPC) remain largely unexplored. Here, miR-197-3p was screened and identified, and whose level was reduced in serum and exosomes of patients with NPC. MiR-197-3p might be a good diagnostic and prognostic indicator. Our data showed that miR-197-3p expression was closely related to radioresistance, apoptosis, proliferation, migration, and survival of NPC. Inhibition of miR-197-3p expression in vitro could promote the proliferation and migration of NPC cells, while promotion of miR-197-3p expression in vivo could significantly inhibit the growth and enhance the radiosensitivity of NPC cells. From the perspective of mechanism, miR-197-3p could inhibit AKT/mTOR phosphorylation activation, inhibit an activated pathway of AKT/mTOR, target Heat Shock 70-kDa Protein 5(HSPA5) related to endoplasmic reticulum homeostasis, inhibit HSPA5-mediated autophagy, and reverse the radioresistance of NPC. Interestingly, exosomal miR-197-3p (EXO-miR-197-3p) reduced the proliferation and migration potential of NPC cells in vitro, and tumor growth and radioresistance of NPC cells in vivo. EXO-miR-197-3p inhibited NPC progression and radioresistance by regulating AKT/mTOR phosphorylation activation and HSPA5-mediated autophagy. In conclusion, our results highlight the potential of EXO-miR-197-3p as an effective radiosensitizer and therapeutic agent for refractory NPC.

[Gastric SWI/SNF-complex deficient undifferentiated/rhabdoid carcinoma: a clinicopathological study]

Objective: To investigate the clinicopathological features, immunohistochemical characteristics, differential diagnosis and prognosis of gastric SWI/SNF-complex deficient undifferentiated/rhabdoid carcinomas. Methods: Two cases of gastric SWI/SNF-complex deficient undifferentiated/rhabdoid carcinoma were collected at Fudan University Shanghai Cancer Center, Shanghai, China from 2017 to 2018. The clinicopathological characteristics were analyzed. Hematoxylin and eosin, and immunohistochemical stains were performed, and the relevant literatures were reviewed. Results: The two patients were both male, aged 60 and 74 years, respectively. Their symptoms were both abdominal pain. The tumor arose in the esophagogastric junction in case 1, and the cardia to the fundus and the posterior wall of the upper part of gastric body in case 2. Both tumors were present as an ulcerative mass. The patients died of tumor 11 months and 8 months after surgery, respectively. Histologically, the tumor cells arranged in sheets, nests, cords or trabecular patterns, and pseudoavleolar structure. The tumor cells were epithelioid with uniform morphology, while the tumors showed scant stroma and massive necrosis. Variable rhabdoid cells and multinucleated giant cells were seen in both cases. SMARCA4 encoding protein BRG1 was undetectable in both tumors, while SMARCB1 encoding protein INI1 was detected. The tumor cells were diffusely positive for vimentin and negative for epithelial marker (CKpan), gastrointestinal stromal tumor markers (CD117 and DOG1), myogenic markers (desmin and myogenin), melanoma markers (S-100 protein, SOX10 and HMB45), and lymphohematopoietic markers (LCA and CD20). Conclusions: Gastric SWI/SNF-complex deficient undifferentiated/rhabdoid carcinoma is a rare and highly aggressive tumor with poor prognosis. The detection of subunits protein expression of SWI/SNF complex is important for diagnosis of the tumor.

[Clinical study on endoscopic surgery for soft tissue necrosis of cranial base after radiotherapy for nasopharyngeal carcinoma]

Objective: To investigate the diagnosis and surgical treatment of patients with soft tissue necrosis of cranial base after radiotherapy for nasopharyngeal carcinoma (NPC). Methods: The clinical data of 7 NPC patients with soft tissue necrosis but not bone necrosis after radiotherapy were retrospectively analyzed.They were treated in Xiangya Hospital from 2015 to 2019. The clinical manifestations, diagnosis, treatment and prognosis were analyzed. The major clinical symptoms of the 7 patients were headache in 7 cases, hearing loss in 7 cases, long-term nasal malodor in 5 cases and epistaxis in 2 cases. All patients underwent high-resolution CT, MR and magnetic resonance angiography (MRA) before operation. All cases were treated with extended transnasal endoscopic approach under general anesthesia for resection of necrotic tissue. Five cases had their affected cartilaginous segments of the eustachian tubes partially or completely resected, 7 cases were treated with myringotomy and tube insertion, and 1 case was treated with pansinusectomy. Anti-inflammatory treatment were carried out during the perioperative period. The recovery of patients was observed and recorded through regular follow-up (from 6 months to 3 years) after the operation. Results: Nasopharynx soft tissue lesions can be seen in seven patients with bone cortex integrity by CT, and small bubble shadow can be seen at junction area between skull base soft tissue lesions and skull base bone surface.MR and MRA examination showed extensive inflammatory changes of nasopharynx. Parapharyngeal irregular necrotic cavity was found in 6 cases without central enhancement, demonstrating edema of surrounding soft tissue. The necrotic tissue of all 7 patients was surgically removed. Postoperative pathological examinations confirmed that all of them were necrotic soft and cartilaginous tissue, without tumor recurrence. The symptoms of all patients were significantly alleviated after operation. Headache was cured in 5 cases and relieved in 2 cases. Nasal malodor was cured in 4 cases and alleviated in 1 case. During the follow-up period, 5 patients survived, and 2 patients who had their eustachian tube reserved died. One of them died of nasopharyngeal hemorrhage caused by recurrent nasopharyngeal necrosis 3 months after the operation. Another case died of severe intracranial infection 6 months after operation. Conclusions: The diagnosis of skull base soft tissue necrosis after radiotherapy for nasopharyngeal carcinoma needs comprehensive analysis of radiotherapy history, clinical manifestations and imaging examination. High resolution CT, MR and MRA of skull base are very important for diagnosis. Early active removal of large-scale necrotic lesions under endoscope and partial or total resection of eustachian tube cartilage according to the involvement of eustachian tube cartilage is effective means of controling skull base soft tissue necrosis after radiotherapy. The effective means of necrosis can improve the quality of life of patients.

The role of urinary renalase on early-stage renal damage in Chinese adults with primary hypertension

It would be of great clinical value to find an indicator that can accurately evaluate the early-stage renal injury in primary hypertension. Previous findings have shown renalase not only plays an important role in hypertension but also closely correlates with kidney function. The purpose of this study is to investigate whether urinary renalase could be used as a predictive index of early-stage renal damage in patients with primary hypertension. Urinary albumin to creatinine ratio (UACR) was used to divide subjects with primary hypertension into two groups: a no renal damage (NRD) group (UACR <30 mg/g) and an early-stage renal damage (RD) group (UACR >30 mg/g). Subjects with normal examination results were randomly included in a healthy control (HC) group. Urinary renalase was determined through an enzyme-linked immunosorbent assay (ELISA). Urinary renalase continued to reduce among the HC (n = 81), NRD (n = 84) and RD group (n = 80), while systolic blood pressure (SBP) increased. Urinary renalase was negatively correlated with SBP in all the groups. Among the subjects with stage 1 primary hypertension, urinary renalase in the RD group was lower than the NRD group, while the UACR was higher, and urinary renalase was negatively correlated with the UACR. A multiple linear stepwise regression analysis showed that there was a linear regression relationship between the increase of the UACR and urinary renalase, heart rate (HR), SBP and serum creatinine. In addition, the standardized partial regression coefficient of urinary renalase was the highest. The performance of urinary renalase as a marker for the diagnosis of early-stage renal damage in patients with primary hypertension was 0.968 with a cut off value of 2.01 µg/ml. Taken together, urinary renalase was further decreased in patients with early-stage renal damage and primary hypertension, and consequently, it could be used as a predictive index.

[Clinical analysis of Langerhans cell histiocytosis originating in the base of nasal skull]

Objective:To summarize the clinical features, diagnosis and treatment of Langerhans histiocytosis（LCH） which first appeared in the nasal skull base. Method:Ten cases of LCH with nasal and skull base symptoms were analyzed retrospectively. The clinical characteristics of LCH with nasal and skull base symptoms were summarized. The correlation of other systems involved in LCH was analyzed. Result:Among the 10 patients, the youngest was 1 year and 5 months, and the oldest was 8 years, the average age was 3 years. The main imaging manifestations were osteolytic changes and soft tissue invasion. Seven patients were monofocal and three patients were multifocal. For localized lesions, radical resection and follow-up chemotherapy were performed, and conservative treatment was performed for patients with multiple system involvement and obvious systemic symptoms. Eight patients survived, 2 died. Conclusion:LCH occurs frequently in children and has certain clinical characteristics. Single system and single lesion surgery have a better therapeutic effect, and can achieve a greater survival rate with follow-up chemotherapy.

[Expression of SMARCA4(BRG1) and SMARCB1(INI1) in dedifferentiated and undifferentiated endometrial carcinomas and their correlations with clinicopathological features]

Objective: To investigate the expression of SMARCA4 (BRG1) and SMARCB1 (INI-1) protein in endometrial dedifferentiated carcinoma (DDC) and undifferentiated carcinoma (UDC), and their correlation with clinicopathologic features. Methods: Clinicopathological information was gathered for 26 cases of DDC and UDC and consulting hospitals from January, 2006 to December, 2018 in Fudan University Shanghai Cancer Center, including 10 cases of DDC and 16 cases of UDC. Morphologic features and diagnosis were reviewed by two pathologists. Immunohistochemistry for expression of BRG1 and INI1 protein was performed. The correlations with clinicopathologic features were analyzed. Results: BRG1 and INI1 loss were present in 14 of 26 cases of DDC/UDC, including 12 BRG1-deficient cases and 2 INI1-deficient cases, respectively. Six cases demonstrated variable amounts of rhabdoid cells in 14 BRG1/INI1-deficient cases, and only 1 case showed rhabdoid cells in the 12 intact expression cases. However, there was no significantly statistical difference (P=0.060). Age, invasive depth, lymph node status and FIGO stage were not associated with the expression of the BRG1 and INI1 (P=0.437, P=0.672, P=0.242, P=0.348). Remarkably, the BGR1/INI1-deficient patients had worse survival than those with intact expression (4.7 vs. 22.9, P=0.033). Conclusion: BRG1/INI1-deficient is observed in approximately half of DDC and UDC. Identification of these tumors is clinically relevant due to their more aggressive behavior and poor prognosis. Hence, BRG1 and INI1 immunohistochemical stains should be performed for DDC and UDC in order to help the pathologists to distinguish these tumors from other carcinomas, and to predict the clinical prognosis.

[Significance of pelvic contrast enhanced MRA prior to prostatic artery embolization]

Objective: To assess the values of pelvic contrast enhanced magnetic resonance angiography (MRA) in detection of prostatic artery prior to prostatic arterial embolization(PAE). Methods: This multicenter, prospective study from 5 hospitals in China consisted of 47 patients (mean age (69±16) years, range 56-83 years) who underwent PAE for benign prostatic hyperplasia (BPH) between January 2016 and April 2018, preprocedural prediction of prostatic arteries were determined using contrast enhanced MRA.CE-MRA findings were compared with subsequent intraprocedural digital subtraction angiography (DSA) or DSA combined with cone-beam computed tomography (CT) to assess the sensitivity and specificity with which contrast enhanced MRA predicted the number and origins of prostatic artery, also to assess the optimal oblique projection of PA. Results: In total, 47 patients (94 pelvic sides) with 97 PAs confirmed by DSA or DSA combined with cone-beam CT at the time of embolization, MR angiography successfully identified 88 PAs and their origins , the sensitivity and specificity was 90.7% (88/97) and 93.6% (88/94), respectively.MR angiography correctly determined the bilateral prostatic artery origins in 36 (76.6%) cases.According to the optimal oblique projection of PAs suggested by MR angiography, the origins and trajectory of PAs of all patients underwent PAE with the same oblique projection (20°-45°ipsilateral anterior oblique direction) were clearly displayed when performed the first arteriography. Conclusion: Pelvic contrast enhanced MR angiography with high sensitivity and specificity in detection the origin, trajectory and number of PAs, and it could provide useful information regarding prostatic arteries before PAE.

A proteomics analysis reveals that A2M might be regulated by STAT3 in persistent allergic rhinitis

BACKGROUND

Proteomics tools can be used to identify the differentially expressed proteins related to allergic rhinitis (AR). However, the large numbers of proteins related to AR have not yet been explored using an advanced quantitative proteomics approach, known as isobaric tags for relative and absolute quantitation (iTRAQ).

OBJECTIVES

To identify differentially expressed proteins in persistent AR patients and to explore the regulatory signalling pathways involving the identified proteins.

METHODS

Forty-five persistent AR patients and 20 healthy controls were recruited for this study. iTRAQ was used to identify the proteins that were differentially expressed between these two groups, and a bioinformatics analysis was then conducted to identify the signalling pathways associated with the identified proteins. Immunofluorescence labelling was performed to detect alpha-2-macroglobulin (A2M), STAT3, p-STAT3 and IL17 in the nasal mucosa.

RESULTS

A total of 133 differentially expressed proteins were identified. We then determined the top 10 regulatory pathways associated with these proteins and found that the blood coagulation pathway had the most significant association. A2M, a protein involved in the blood coagulation pathway, was found to be differentially expressed in the serum of AR patients. The bioinformatics analysis indicated that STAT3 is an upstream transcription factor that might regulate A2M expression. An immunofluorescence study further confirmed that STAT3 and A2M are co-localized in nasal mucosa cells. Additionally, A2M, STAT3, p-STAT3, and IL17 are elevated in AR patients. The expressional level of A2M is positively related to IL17 and the symptom of the congestion in AR subjects.

CONCLUSIONS

The blood coagulation pathway may be a key regulatory network pathway contributing to the allergic inflammatory response in AR patients. A2M, which is regulated by STAT3, may be an important protein in the pathogenesis of allergic rhinitis in AR patients.

[Clinical practice of transnasal endoscopic operation for retrobulbar lesions]

Objective: To summarize the skill and experience of transnasal endoscopic operation for retrobulbar lesions. Methods: Seven patients aged from 25 to 67 years old diagnosed as retrobulbar lesions who underwent transnasal endoscopic operation in Department of Otorhinolaryngology Head and Neck Surgery, Xiangya Hospital between January 2013 and October 2016 were retrospectively analyzed. Two males and five females were included in this study. Five patients underwent transnasal endoscopic operation via media rectus-inferior rectus space, with the other 2 cases via media rectus-superior rectus space. Results: Total lesion removal was achieved in 6 of 7 patients, while 1 patient underwent subtotal removal of the lesion. The visual acuity and visual field improved in 3 cases. The pathological examination showed hemangioma(5 cases), bone cyst(1 case) and fibroma(1 case). All patients were followed up for 9 months to 4 years without complications such as eye movement disorder or blindness, except for 1 case with preoperatively proptosis occurred postoperatively transient diplopia. There was no recurrence in 6 patients with total lesion removal, and the patient underwent subtotal removal of fibroma did not undertake operation again. Conclusion: Transnasal endoscopic operation for retrobulbar lesions is a minimally invasive, safe and effective operatiiv method, which could be taken via different surgical approaches according to the size and location of the lesion.

Direct Involvement of the Master Nitrogen Metabolism Regulator GlnR in Antibiotic Biosynthesis in Streptomyces

GlnR, an OmpR-like orphan two-component system response regulator, is a master regulator of nitrogen metabolism in the genus Streptomyces In this work, evidence that GlnR is also directly involved in the regulation of antibiotic biosynthesis is provided. In the model strain Streptomyces coelicolor M145, an in-frame deletion of glnR resulted in markedly increased actinorhodin (ACT) production but reduced undecylprodigiosin (RED) biosynthesis when exposed to R2YE culture medium. Transcriptional analysis coupled with DNA binding studies revealed that GlnR represses ACT but activates RED production directly via the pathway-specific activator genes actII-ORF4 and redZ, respectively. The precise GlnR-binding sites upstream of these two target genes were defined. In addition, the direct involvement of GlnR in antibiotic biosynthesis was further identified in Streptomyces avermitilis, which produces the important anthelmintic agent avermectin. We found that S. avermitilis GlnR (GlnRsav) could stimulate avermectin but repress oligomycin production directly through the respective pathway-specific activator genes, aveR and olmRI/RII To the best of our knowledge, this report describes the first experimental evidence demonstrating that GlnR regulates antibiotic biosynthesis directly through pathway-specific regulators in Streptomyces Our results suggest that GlnR-mediated regulation of antibiotic biosynthesis is likely to be universal in streptomycetes. These findings also indicate that GlnR is not only a master nitrogen regulator but also an important controller of secondary metabolism, which may help to balance nitrogen metabolism and antibiotic biosynthesis in streptomycetes.

Integrated microRNA-mRNA analysis of pancreatic ductal adenocarcinoma

The main aim of this study was to explore the underlying molecular mechanisms and potential target molecules of pancreatic adenocarcinoma. The miRNA (GSE32678) and mRNA (GSE32676) expression profiles of patients with pancreatic ductal adenocarcinoma and healthy controls were downloaded from the Gene Expression Omnibus database. Differentially expressed miRNA and differentially expressed genes were identified by analyzing the microarray algorithm after data preprocessing. Functional analysis was conducted by the Database for Annotation, Visualization and Integrated Analysis. miRNA-mRNA regulation pairs were obtained in TarMir database. The node degree of hsa-miR-200c, hsa-miR-429, and hsa-miR-200b (miRNA), and EFNB2, MYRIP, and PHF17 (mRNA) were extremely high in the miRNA-mRNA network, indicating that these miRNA and mRNA may play a key role in the development of pancreatic cancer. Our study screened out some target miRNAs and mRNAs for pancreatic ductal adenocarcinoma, which may be helpful in its diagnosis and treatment.

The effects of catheter-based radiofrequency renal denervation on renal function and renal artery structure in patients with resistant hypertension

There are no clinical studies on the effects of catheter‐based radiofrequency renal denervation (RDN) on renal artery structure using 64‐detector computed tomography (CT). A total of 39 patients with resistant hypertension received RDN and 38 patients received drug treatment. Mean systolic pressure and diastolic pressure in the RDN group decreased after 1, 3, 6, and 12 months of procedure (P<.05) and urinary protein level significantly decreased after 6 and 12 months (P<.05). The diameter, length, and sectional area of the renal artery; number of cases of atherosclerosis; and plaque burden of 64‐detector CT renal arteriography did not change at 12 months of follow‐up (P<.05), whereas the plaque burden increased significantly in the control group (P<.05). RDN significantly and persistently reduced blood pressure and decreased urinary protein excretion rate in patients with resistant hypertension and did not exhibit any adverse effect on renal function and renal artery structure.

Characterization of human umbilical cord mesenchymal stem cells following tissue mass culture

The human umbilical cord represents a promising resource of mesenchymal stem cells (MSCs). In order to improve our understanding of MSCs derived from human umbilical cord (UC-MSCs), we isolated UC-MSCs from human umbilical cord tissues through a direct culture approach. We performed a comprehensive characterization of these cells based on analyses of morphology, growth features, cell surface antigen markers and differentiation capacity. All these analyses validated their stem cell nature. The UC-MSCs presented a spindle-shaped morphology and could be subcultured for up to 15 passages without losing their cellular features. Moreover, these UC-SMCs presented an expression profile of cell surface antigens similar to other MSCs: positive for CD44, CD90, and CD105 expression and negative for CD34, CD31, and CD45 expression. Differentiation assays further validated the multipotency of UC-MSCs by inducing these cells into osteoblasts, adipocytes and functional hepatocytes. Our studies clearly demonstrated that UC-MSCs resemble other types of MSCs in many aspects and have a great potential to be applied in tissue engineering and regenerative medicine.

[Effect of renal sympathetic denervation on left ventricular hypertrophy and inflammatory factors in spontaneously hypertensive rats]

OBJECTIVE

To investigate the effect of renal sympathetic denervation on left ventricular hypertrophy and inflammatory factors in spontaneously hypertensive rats.

METHODS

Thirty six spontaneously hypertensive rats (SHR) were divided into 3 groups with 12 animals in each group: SHR control group,operation group and sham operation group. Bilateral renal sympathectomy or sham operation were performed in operation and sham groups,respectively; another 12 WKY rats served as normal controls. The blood pressure and body weight were examined weekly. The animals were sacrificed at w1 and w6, rat hearts were collected and left ventricular mass index (LVMI) was calculated. The expression of TLR4,TNF-α and IL-6 in heart tissue were detected by immunohistochemistry and Western blot.

RESULTS

The systolic blood pressure [(201.67 ± 11.09) mmHg compared with (140.0 ± 10.86)mmHg,P<0.05],diastolic blood pressure [(144.50 ± 10.48)mmHg compared with (78.50 ± 7.32)mmHg,P<0.05], LVMI (2.44 ± 0.05 compared with 1.93 ± 0.05,P<0.05),the expression of TLR4 (0.298 ± 0.004 compared with 0.126 ± 0.004, P<0.05), NF-κB (0.249 ± 0.006 compared with 0.195 ± 0.005, P<0.05),TNF-α(0.323 ± 0.004 compared with 0.146 ± 0.004,P <0.05), IL-6 (0.283 ± 0.005 compared with 0.207 ± 0.006, P<0.05) in SHR control group were significantly higher than those in WKY group. Compared to sham operation group,the systolic blood pressure (157.30 ± 9.35 compared with 197.30 ± 11.5, P<0.05),diastolic blood pressure (112.50 ± 6.25 compared with 146.80 ± 7.6, P<0.05),LVMI (2.32 ± 0.04 compared with 2.57 ± 0.09, P<0.05, TLR4 (0.198 ± 0.006 compared with 0.317 ± 0.008, P<0.05), NF-κB (0.208 ± 0.006 compared with 0.332 ± 0.007, P<0.05), TNF-α(0.27 ± 0.009 compared with 0.375 ± 0.004,P<0.05), IL-6 (0.218 ± 0.004 compared with 0.376 ± 0.009, P<0.05) in operation group were all decreased at w1 after sympathectomy. Six weeks after the operation,there were no significant differences in systolic blood pressure (197.50 ± 12.13 compared with 208.83 ± 10.23,P>0.05) and diastolic blood pressure (150.33 ± 7.74 compared with 151.50 ± 8.22, P>0.05) between denervated and sham-operated SHRs; however,the LVMI (2.46 ± 0.07 compared with 2.81 ± 0.05,P<0.05) and the expression of TLR4(0.301 ± 0.009 compared with 0.567 ± 0.006, P<0.05), NF-κB (0.251 ± 0.004 compared with 0.476 ± 0.009,P<0.05),TNF-α(0.324 ± 0.005 compared with 0.535 ± 0.006, P<0.05,IL-6 (0.285 ± 0.009 compared with 0.549 ± 0.007, P<0.05) in operation group were still significantly lower than those in sham operation group.

CONCLUSION

Renal sympathetic denervation can significantly delay the progression of LVH in SHR, which may associated with lowering blood pressure and decreasing expression of TLR4, NF-κB,TNF-α, IL-6 in myocardial tissue.

[Resection of parapharyngeal neoplasms via styloid diaphragm approach]

OBJECTIVE

To evaluate the surgical technique and efficacy of the resection of parapharyngeal space neoplasm via styloid diaphragm approach.

METHODS

Thirty-three cases underwent the resection of parapharyngeal space tumors via styloid diaphragm approach from Jan 2005 to Jan 2011 were reviewed. Of the cases, 28 were with benign tumors treated by surgery alone, and 5 were malignant tumors treated by surgery plus postoperative radical radiotherapy.

RESULTS

The parapharyngeal neoplasms in all cases were completely resected via styloid diaphragm approach. The postoperative follow-up ranged from 13 months to 7 years (median = 4.6 years). No tumor recurrence was found in 30 cases, but 3 cases experienced tumor recurrence, including 1 chondrosarcoma (3 years after surgery and chemoradiotherapy), 1 chordoma and 1 adenoid cystic carcinoma (5 years after surgery and radiotherapy). Severe postoperative complications were not observed, but 2 cases showed mild mouth askew and fully recovered after 3 months, and 1 case was complicated with hoarseness and cough symptoms that disappeared after heteropathy.

CONCLUSION

Resection of parapharyngeal neoplasms via styloid diaphragm approach is an ideal surgical technique, with well-exposed surgical field, less tissue injury, and less postoperative complication.

Effect of orange peel essential oil on oxidative stress in AOM animals

The processing parameters of pump speed, inlet air temperature, outlet air temperature and homogenization pressure were evaluated. Encapsulation efficiency is high with a satisfied releasing rate. Then, acute otitis media (AOM) animal model was built and diet containing orange peel essential oil microcapsules were administrated to AOM animals. Pharmacological test showed that orange peel essential oil treatment could decrease serum and cochlea malondialdehyde (MDA), immunoglobulins A (IgA), immunoglobulins G (IgG), immunoglobulins M (IgM) levels and increase antioxidant enzymes activities. It can be concluded that orange peel essential oil treatment could decrease oxidative injury in acute otitis media rats.

[Endoscopic posterior septectomy for patients with nasopharyngeal tumor]

OBJECTIVE

To explore the techniques, advantages and disadvantages, indications and cautions of a surgical approach for the resection of nasopharyngeal tumor.

METHODS

Ten cases with nasopharyngeal tumors were recruited in this study, of them, 3 cases with residual nasopharyngeal carcinoma after chemoradiotherapy, 2 cases with cavernous angioma, 2 cases with benign mixed tumor, 1 malignant mixed tumor, 1 adenoid cystic carcinoma, and 1 chordoma. All patients underwent endoscopic resection of posteroinferior quarter part of nasal septum, and then the removal of nasopharyngeal tumors through bilateral transnasal approach.

RESULTS

Total resection of the tumor was achieved for all cases without severe surgical complications. All cases with benign tumors, with following-up of 6-18 months, showed no recurrence. Of 6 cases with malignant tumors, with following-up of 12-48 months, 5 cases showed no recurrence, and 1 case was suspected to relapse one year postoperatively, but not with any lesion enlargement after another 6 month follow-up.

CONCLUSIONS

Posteroinferior quarter part of nasal septectomy is preferred for endoscopic resection of nasopharyngeal tumors because it can provide a panoramic view on nasopharyngeal cavity and tumors, thus, facilitating the removal of nasopharyngeal tumors.

Emergency removal of a grinding wheel embedded in the midface via modified Le Fort I osteotomy

Le Fort I osteotomy is commonly used to rectify craniofacial deformity in orthognathic surgery and it can be used in approaching a cranial base lesion. This technique has not been well documented in craniofacial penetrating trauma. This article describes a case of midface penetrating injury caused by a grinding wheel. A modified Le Fort I osteotomy was used to remove the foreign object. This surgical approach can be safe and effective when removing foreign bodies in the midface. Good access and adequate exposure can be achieved, which facilitate precise foreign body extraction and achieve reasonable cosmetic results.

[Prevention and management of complications of endoscopic surgery for nasal-skull base neoplasms]

OBJECTIVE

To analyze the surgical complications of endoscopic nasal-skull base surgery. The secondary objective was to propose the preliminary strategies for prevention and treatment of complications.

METHODS

One hundred and thirty two patients with nasal-skull base tumors undergoing endoscopic or endoscope-assisted surgery were included in this study. Surgical approaches included endoscopic endonasal transethmoidal approaches, endoscopic endonasal transseptal transsphenoidal approach, extended endoscopic endonasal transseptal transsphenoidal approach, endoscopic transmaxillary posttrial wall approach, extended endoscopic transmaxillary posttrial wall approach, endoscopic nasal lateral wall dissection, maxillary osteotomy approach and endoscopic transoropharyngeal approach. These approaches were selectively used to resect the tumors in the area of nasal-skull base.

RESULTS

The total resection of the tumors was obtained in 104 patients (104/132, 78.8%), with 29.5% (39/132) incidence of complications, including profuse bleeding, nerve injury, cerebrospinal fluid leakage, diabetes insipidus, electrolyte imbalance, hyperglycemia, and psychological disturbance. No catastrophic complications, sequelae and operative mortality encountered. Four months to 8 years' follow up (median 3.0 years) indicated that recurrence rate of the benign tumor was 9% (9/100) without died case, and 3-year and 5-year survival rates of the malignant tumor were 75.0% and 55.6%, respectively.

CONCLUSIONS

Strategies proved to be effective in reduction of the overall incidence of the complications, especially in minimizing the catastrophic complications and sequelae. The strategies were as follows: first, according to original site, extension and characteristics of the tumor, designing appropriate endoscopic approaches for the treatment of skull base tumor; second, recognizing reliable surgical access points and safe plane of the dissection; third, predicting surgical risks preoperatively and proposing the corresponding plan to avoid these risks; fourth, acquainted with the endoscopic skills and familiarized the skull base structures; lastly, ensuring the correct management of the interdisciplinary problems with close collaboration with the interdisciplinary medical personnels.

Identification and characterization of glnA promoter and its corresponding trans-regulatory protein GlnR in the rifamycin SV producing actinomycete, Amycolatopsis mediterranei U32

The genetic requirements for the transcription of glnA, encoding the major glutamine synthetase in a rifamycin SV-producing Amycolatopsis mediterranei strain, U32, were investigated. Primer extension experiments showed that the promoter of U32 glnA (pglnA) was likely to have two transcription initiation sites: P(1) and P(2), located 157 and 45 nucleotides (nt) upstream of the translational start codon, respectively. Gel mobility shift and DNase I footprinting analyses revealed a 30 bp cis-element located at 45 to 75 nt downstream of P1, or 38 to 68 nt upstream of P(2). The sequence of the cis-element displayed high similarity to the corresponding regions of pglnA from Streptomyces coelicolor and S. roseosporus. With xylE as a reporter gene, the expression levels of U32 pglnA and its deletion derivatives under different nitrogen-source conditions were analyzed by detecting the catechol dioxygenase activities in S. lividans TK54, S. coelicolor J508 and S. coelicolor FS10 (glnR mutant). These in vivo studies showed that the activation of U32 pglnA in S. coelicolor required GlnR, and its binding to the U32 pglnA was further confirmed by the gel mobility shift assay. Cloning and heterologous expression of the U32 glnR allowed us to detect the in vitro interaction between the U32 GlnR and the corresponding pglnA cis-element. Further evidence shown by in vivo glnR inactivation and complementation indicated that GlnR is essential for the active transcription of glnA in U32.

[Quantitative and localized detection of Epstein-Barr virus infectious status in nasopharyngeal carcinoma tissue]

BACKGROUND & OBJECTIVE

Epstein-Barr virus (EBV) closely relates to nasopharyngeal carcinoma (NPC). Whether EBV is a causative viral agent or a by-stander in the carcinogenesis of NPC needs further study. The latent status of EBV during carcinogenesis of NPC remains unknown nowadays. This study was to explore the infectious status of EBV in NPC, and analyze the correlation of EBV to carcinogenesis of NPC.

METHODS

Carcinoma tissues,adjacent tissues, and contralateral normal nasopharyngeal tissues from 47 patients with poorly-differentiated nasopharyngeal squamous cell carcinoma were prepared simultaneously. Nasopharyngeal tissues from 10 healthy subjects were used as control. EBV DNA copies levels in the specimens were tested using real-time quantitative polymerase chain reaction (PCR); localization of EBV was detected by in situ hybridization [digoxigenin-labeled EBV-encoded RNA 1 (EBER-1) probe].

RESULTS

Infectious rate of EBV was 80.0% in nasopharyngeal tissues of healthy subjects (mean EBV DNA copies of 6.7x10(2)/microg DNA), 100% in carcinoma tissues and adjacent tissues of NPC patients, and 72.3% in contralateral normal nasopharyngeal tissues of NPC patients (mean EBV DNA copies of 6.9x10(5)/microg DNA, 1.5x10(5)/microg DNA, and 9.8x10(3)/microg DNA, respectively). There was no significant difference in infectious rate and level of EBV between controlateral normal nasopharyngeal tissues of NPC patients and nasopharyngeal tissues of healthy subjects (P>0.05); infectious level of EBV was significantly higher in carcinoma tissues than in adjacent tissues (P<0.05), and significantly higher in adjacent tissues than in contralateral normal nasopharyngeal tissues of NPC patients (P<0.01). Using in situ hybridization, EBER-1 expression signal was not detected in contralateral normal nasopharyngeal epithelia of NPC patients, weak in atypical hyperplastic cells in adjacent tissues, and strong in carcinoma cells.

CONCLUSIONS

EBV latent infection is a common phenomenon in nasopharyngeal tissues of both NPC patients and healthy persons. The enhancement of EBV infection plays an important role during carcinogenesis of NPC.

Synthetic peptides derived from SARS coronavirus S protein with diagnostic and therapeutic potential

The spike (S) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is an important viral structural protein. Based on bioinformatics analysis, 10 antigenic peptides derived from the S protein sequence were selected and synthesized. The antigenicity and immunoreactivity of all the peptides were tested in vivo and in vitro. Four peptides (P6, P8, P9 and P10) which contain B cell epitopes of the S protein were identified, and P8 peptide was confirmed in vivo to have a potential in serological diagnosis. By using a syncytia formation model, we tested the neutralization ability of all 10 peptides and their corresponding antibodies. It is interesting to find that P8 and P9 peptides inhibited syncytia formation, suggesting that the P8 and P9 spanning regions may provide a good target for anti-SARS-CoV drug design. Our data suggest that we have identified peptides derived from the S protein of SARS-CoV, which are useful for SARS treatment and diagnosis.

[Detection of RNA interference in nasopharyngeal carcinoma cell lines using reporter genes]

BACKGROUND & OBJECTIVE

RNA interference (RNAi) technique is now widely used in studies of gene function, signal transduction pathway, and gene therapy because it can effectively and specifically inhibit gene expression. This study was designed to synthesize small interfering RNA (siRNA) by in vitro transcription, and construct retrovirus vectors to express small hairpin RNA (shRNA), detect RNAi in nasopharyngeal carcinoma cell lines, and to develop a RNAi technique platform.

METHODS

siRNAs targeting green fluorescent protein (GFP) and luciferase (Luc) were synthesized by in vitro transcription, while shRNAs targeting GFP and Luc were constructed from pSUPER.retro. Cervical cancer cell line HeLa, nasopharyngeal carcinoma cell lines CNE1, CNE2, and 5-8F were co-transfected with siRNAs or shRNAs and reporter gene pEGFP-N1 or pGL3. The expression of GFP was detected by fluorescent microscopy and Western blot. The activity of luciferase was measured by Luciferase Enzyme Assay System.

RESULTS

siRNA duplexes with 3' UU overhangs and shRNA specifically silenced GFP expression, while antisense RNA and siRNA without 3' UU overhangs did not trigger RNA interference of GFP. Quantitative luciferase activity analysis showed that siRNA inhibited Luc expression in HeLa, CNE1, CNE2, and 5-8F cell lines with inhibition rates of 91.43%, 78.01%, 90.30%, and 62.85%, respectively. Similarly, the inhibition rate was 78.22% when shRNA targeting Luc was co-transfected into HeLa cell line.

CONCLUSIONS

Both siRNAs and shRNAs can induce RNAi. 3' UU overhangs of siRNA may play a role in RNAi. RNAi can be triggered in both nasopharyngeal carcinoma cell lines and HeLa cell line.

VdNEP, an elicitor from Verticillium dahliae, induces cotton plant wilting

Verticillium wilt is a vascular disease of cotton. The causal fungus, Verticillium dahliae, secretes elicitors in culture. We have generated approximately 1,000 5'-terminal expressed sequence tags (ESTs) from a cultured mycelium of V. dahliae. A number of ESTs were found to encode proteins harboring putative signal peptides for secretion, and their cDNAs were isolated. Heterologous expression led to the identification of a protein with elicitor activities. This protein, named V. dahliae necrosis- and ethylene-inducing protein (VdNEP), is composed of 233 amino acids and has high sequence identities with fungal necrosis- and ethylene-inducing proteins. Infiltration of the bacterially expressed His-VdNEP into Nicotiana benthamiana leaves resulted in necrotic lesion formation. In Arabidopsis thaliana, the fusion protein also triggered production of reactive oxygen species and induced the expression of PR genes. When added into suspension cultured cells of cotton (Gossypium arboreum), the fusion protein elicited the biosynthesis of gossypol and related sesquiterpene phytoalexins at low concentrations, and it induced cell death at higher concentrations. On cotton cotyledons and leaves, His-VdNEP induced dehydration and wilting, similar to symptoms caused by a crude preparation of V. dahliae elicitors. Northern blotting showed a low level of VdNEP expression in the mycelium during culture. These data suggest that VdNEP is a wilt-inducing factor and that it participates in cotton-V. dahliae interactions.

[Expression, purification and identification of recombinant SARS coronavirus membrane protein]

A novel coronavirus (SARS-coronavirus, SARS-CoV) was discovered as the pathogen of the severe acute respiratory syndrome (SARS). According to studies with other coronaviruses, the membrane protein (M protein) is the main structural protein and the recombinant M protein may be useful as an antigen for detecting antibodies against coronavirus and for preparing vaccine. In this work, the M protein of SARS-CoV was expressed in E. coli as fusion protein with maltose binding protein at N-terminus and MxeGyrA intein CBD at C-terminus. The recombinant protein was identified by Western blot and mass spectrometry. The soluble parts of the cell crude extract were then partially purified by MBP affinity chromatography. The purified protein will be used for the studies on M protein's structure and the development of diagnostic method of SARS.

[Sequence and functional analysis of the chromosome replication origin (oriC) of Streptoverticillum caespitosus ATCC27422]

Twenty-two DnaA boxes were identified in the chromosome replication origin (oriC) of Streptoverticillum caespitosus ATCC27422 based upon the characteristics of consensus sequences. The 21st and 22nd DnaA boxes overlapped 8 base pairs each other reversely. Compared with the oriC database of actinomycetes, similar overlapping DnaA boxes were recognized in several species of Streptomyces and Mycobacterium. These overlapping DnaA boxes were composed of the last two DnaA box (21st and 22nd) in the Streptomyces species, but the of 1st and 2nd ones in the Mycobacterium species. The consensus sequence of the overlapping DnaA box is CTGTGCACAA, one base longer than the normal DnaA box sequence presumably due to the overlapping structure. Although the DnaA boxes exist in the 189 792 bp region only, the 1 188 bp and 793 939 bp regions are also important to the DNA replication. Deletion of the 1 188 bp region may cause absolute loss of DNA replication initiation activity measured by the transformation efficiency of plasmids with truncated oriC. When the 793 939 bp region was truncated, the transformation efficiency reduced about 40%. If the oriC was cloned into a vector with partial flanking region sequences (partial dnaA and dnaN gene sequences), the transformation rate was about 4.3-fold lower than that of the construct containing the oriC region only. However, the transformants were much more similar to the host with respect to the morphology of colony and mycelium. The cis-regulatory functions of the flanking sequences, which may influence the initiation efficiency of the chromosome replication and/or the stability of replicon, are thus suggested.

[Expression and purification of recombinant SARS coronavirus spike protein]

A novel coronavirus (SARS-coronavirus, SARS-CoV) was discovered in association with cases of severe acute respiratory syndrome (SARS) recently. The first step in coronavirus infection is binding of the viral spike protein to certain receptor on host cells. The spike protein is the main surface antigen of the coronavirus and there should be antibodies against spike protein in patients serum. Thus, to develop and expression protein fragment from spike protein gene are the purposes of this experiment. Partial spike gene fragments (751-1925 bp, 2005-3410 bp, 1-1925 bp and 32-3659 bp) and its intact gene were cloned into pET32 or pGEX vectors, and transformed into competent Escherichia coli BL21(DE3) (pLysS), respectively. 63, 78, 98, 160 and 164 kD fusion proteins were successfully expressed with amounts of 35%, 34%, 24%, 17% and 5% of total cell protein. The soluble parts of the cell crude extract were then partially purified by GST affinity chromatography.

[Isolation and characterization of functional replication origin from Streptomyces avermitilis]

Most eubacteria contain highly conservative gene clusters in the adjacent regions of oriC. According to this principle, a 1.4 kb DNA fragment containing parts of dnaA and dnaN genes of Streptomyces avermitilis was cloned by degenerate PCR. Sequence analysis of this fragment indicated that it encoded two partial genes in the order dnaA (the putative initiator protein) and dnaN (the beta subunit of DNA polymerase III). The intergenic non-coding region between dnaA and dnaN was found to contain 19 putative DnaA boxes, i.e. 9 nt long DnaA protein recognition sequences. It was confirmed that the location, orientation and spacing of DnaA boxes in this intergenic region are conserved among Streptomyces. The consensus sequence of DnaA box identified is (T/C)(T/C)(G/A/C)TCCACA (preferred bases in italic). When this fragment was cloned into Escherichia coli plasmid pQC156, which is otherwise non-replicative in Streptomyces, it exhibited autonomous replication activity in Streptomyces lividans, a closely related Streptomyces strain. Different parts of the oriC contribute unequally to the stability and transformation efficiency. The 3' region of oriC may contain features that support stable autonomous replication. The implications of these results for the understanding of the S. avermitilis oriC replication initiation process and its future application are discussed.

[Cloning of the replication origin (oriC) of Streptoverticillum caespitosus and transformation of Streptomyces lividans ZX7]

Streptoverticillum caespitosus ATCC27422 is a producing strain of mitomycin A for cancer therapy. Taking the advantage of the conserved sequences of genes flanking the oriC of high G + C Gram-positive bacteria, a 1.3 kb DNA fragment containing oriC and its flanking region was cloned by PCR. Nuleotide sequence comparisons revealed that the cloned fragment is more than 80% identical to the same region of S. coelicolor. There are 22 DnaA-boxes in the oriC region, and the conserved sequence of DnaA-box is TTGTCCACA. The plasmid containing the oriC of S. caespitosus was constructed (pMJ9), and it was able to transform the protoplast of Streptomyces lividans ZX7 at the frequency of 3.2 x 10(2) transformants/micrograms plasmid DNA. The colony and mycelia's morphology of the transformants are normal. The constructed plasmid can exist stable in the host as a low copy extra-chromosome replicon. The high rate of the homology and the cross genus replication initiation activity suggests close relationship between Streptomyces and Streptoverticillum in the evolution. While the maximum likelihood phylogenetic tree based upon the oriC of S. caespitosus and several Streptomyces spp. revealed that S. caespitosus differed extensively from the Streptomyces spp. This result supports the separation of Streptoverticillum from Streptomyces.

Secretory Expression of GL-7-ACA Acylase in E. coli

The gene of beta-subunit of GL-7-ACA acylase [7beta-(4-carboxybutanamido) cephalosporanic acid acylase] was cloned into pTrc99B, an IPTG inducible pasmid, to form the recombinant called pTrc-CA1B. Another recombinant plasmid pTrcCA1S was obtained by cloning the gene encoding alpha-subunit of GL-7-ACA acylase, the signal peptide and the expression elements from Pseudomonas sp. into pTrcCA1B. Then, recombinant plasmid pKKCA1S was constructed by cloning the gene encoding the signal peptide, expression elements and GL-7-ACA acylase into the vector pKK235. pTrcCA1S and pKKCA1S were allowed to transform TG1. These two plamids were able to transfer the expression product into the periplasmic space of the host bacteria. As a result, in the whole cell of TG1/pTrcCAIS, the specific activity of GL-7-ACA acylase was 23.9 u/g cell, 8 fold higher than that of TG1/pMR24. And in the whole cell of TG1/pKKCA1S, the specific activity of acylase was 18.3 u/g cell, 6 fold higher than that of TG1/pMR24.

Site-directed Mutagenesis of the Active Center of Penicillin Acylase from E. coli ATCC 11105

Site-directed mutagenesis and chemical modification were performed at Ser290 of the penicillin G acylase from E. coli ATCC11105. The Ser290 was substituted by Cys or Secys. Wild type and mutant proteins were purified, and the activities and kinetic constants of penicillin acylases for hydrolysis and synthesis were determined, respectively. Although their K(m) values were not changed, the k(cat) values of the thiol-PGA and seleno-PGA were decreased from 135s(-1) to 0.63s(-1) and 0.38s(-1) against NIPAB, and from 34.38s(-1) to 0.23s(-1) and 0.06s(-1) against penicillin G. Contrary to Choi's report(Choi K S (et al. J Bacteriology), 1992, 10 6270-6276), we found that hydrolysis activity was certainly kept in the mutant of penicillin acylase. In addition, the specific activities of synthesis were decreased by 5-fold and 20-fold, respectively.

Cloning and Overexpression of the Mitomycin C Resistance Gene (mcr) from Streptoverticillium caespitosum

Streptoverticillium caespitosum ATCC27422 is a major producer of an anti-cancer drug, mitomycin C. A 6.6 kb DNA fragment containing the mitomycin C resistance gene (mcr) was isolated from ATCC27422 by shotgun method in order to learn the molecular mechanism of mitomycin C resistance. By constructing a series of subclones from this 6.6 kb DNA fragment, the mitomycin C resistance gene was localized on a 3.1 kb DNA fragment. Sequence analysis revealed that the open reading frame of mcr gene was 1 347 bp in size, encoding 448 amino acids with ATG as initiation codon and TGA as termination codon. The mcr gene was specifically expressed under the control of T7 promoter in E.coli, and the resistance to mitomycin C in the transformant was over 100-fold higher than that in wild-type strain. The overexpression of mcr gene in E.coli is very helpful for the further research about the molecular mechanism of drug resistance.

Expression of gene encoding GL-7ACA acylase in Escherichia coli

Glutaryl 7-amino cephalosporanic acid acylase (GL-7ACA acylase) from Pseudomonas sp.130 catalyzes hydrolysis of glutaryl 7-amino cephalosporanic acid to produce 7-amino cephalosporanic acid (7-ACA). 7-ACA is the starting material for the industrial production of most cephalosparonic derivatives. Six plasmids for expression of GL-7ACA acylase were constructed and these recombin ant plasmids presented different expression characteristics in Escherichia coli. The acylase gene from plasmid pKKCA1 was inserted into plasmid pMFT7-5 and the resulting plasmid pMFT7CA1 has higher expression in E.coli. The specific activity of the crude extract of the transformant JM109(DE3)/pMFT7CA1 was near 5 u/g, so the over produced enzyme was easily purified by a single-step anion exchange column chromatography. The enzyme could be purified by immobilized ion affinity chromatography after fused by 6xHis in the N-terminal of its alpha-subunit. Because plasmid pSMLCA1 brings tc(R) and p15A origin, it is special useful plasmid in fermentation. Two secretory expression plasmids, pSUCA1S and pETCA1pelB, could secrete the acylase to periplasmic space of bacteria. The whole cells containing the secretory expression plasmid may be used for production of 7-ACA directly.

[Establishment of gene replacement/disruption system through homologous recombination in Amycolatopsis mediterranei U32]

A gene replacement/disruption system of Amycolatopsis mediterranei U32 was developed based on the established electroporation conditions as well as appropriate selective markers. Through two-step selection, ahbas gene in U32 was replaced by a promoterless alpha-amylase gene constructed on the plasmid pDK110 of E. coli. The first single-crossover and the second double-crossover frequencies were approximately 0.5%-0.7% and 2%, respectively. Denaturation of the plasmid pDK110 increased the integration frequency about 7-10 folds, while electric shock treatment of the single-crossover recombinants increased the frequency of second crossover recombination about 5 folds. Employing denatured DNA fragments containing an apramycin-resistance gene flanked with regions of the respective genes, One-step disruption of rifO and amrA genes of U32 was also achieved with an efficiency of 30-50 transformants per microgram of DNA.

Mutagenesis of N-terminal Amino Acid Residues in beta-subunit of Glutaryl-7-amino-cephalosporanic Acid Acylase C130

In many GL-7ACA acylases, the first Ser residue at the N-terminal of beta-subunit is the catalytic center. In order to investigate relationship between the N-terminal structure and catalytic activities, peptide replacement and site-directed mutagenesis were performed at the N-terminal of beta-subunit of GL-7ACA acylase C130. When the N-terminal 8 amino acid residues of C130 were replaced by the corresponding sequence of penicillin acylases PAC and PGA, respectively, the first mutant B8PAC lost the activity of the acylase, and the second mutant B8PGA had lower activity with the K(m) value increasing from 0.44x10(-3)mol.L(-1) to 0.55x10(-3) mol.L(-1), and the k(cat) decreasing from 4.92 s(-1) to 1.64 s(-1). Although the substitution of Trp (beta4) by Tyr did not change the K(m) value, the k (cat) decreased to 2.29 s(-1). When the Trp was substitued by Leu, both the K ( m ) and k ( cat ) values decreased. Compared with the wild type, mutations of Ser (beta3) to Met, Ala and Cys caused decrease of K(m) values by 52.27%, 43.18% and 38.64%, respectively. Mutation of Asn (beta2) to Gln caused the K ( m ) value being increased by 5-fold, and k ( cat ) decreased by 10-fold. These results suggested that the N-terminal amino acid residues of beta-subunit in GL-7ACA acylase C130 are important for enzyme function.

[Nucleotide sequence and protein sequence analysis of GL-7-ACA acylase from Pseudomonas sp. 130]

The nucleotide sequence and N-, C-terminal amino acid sequences of alpha,beta-subunit of glutaryl 7-ACA acylase C130 from Pseudomonas sp. 130 were determined. The alignment of the acylase C130 with the other acylases shows that it has high homology with the acylases from Pseudomonas sp. GK16 and C427, but low homology with the others. There is large difference in the N-terminal of alpha-subunit, while the N-terminal of beta-subunit has significant conservation.

[Cloning, sequencing and high expression in Escherichia coli of D-hydantoinase gene from Burkholderia pickettii]

A strain, MMR003, used for D-p-HPG production in industry was classified as Burkholderia pickettii by morphological observation and biochemical characterization. The gene encoding the D-hydantoinase enzyme was cloned, sequenced and expressed in Escherichia coli. The nucleotide sequence of the 5.0 kb insert of subclone pXZ-total was determined. One open reading frame of 1374 bp was found and predicted to encode a polypeptide consisting of 458 amino acids in size of 50 kD. The amino acid sequence alignment of D-hydantoinase from Burkholderia pickettii shows the 85% homologous with the corresponding enzyme from Agrobacterium radiobacter NRRL B11291. The D-hydantoinase gene (dha) harboured in the plasmid pXZPH2 in E. coli BL21(DE3) was highly expressed by IPTG induction. The D-hydantoinase activity for D, L-p-hydroxyphenylhydantion is 0.66 u/mL broth, which is 2-fold increase compared to the parent strain Burkholderia pickettii.

[Establishment of detective systems for GL-7ACA acylase expression]

Glutaryl-7-amino cephalosporanic acid (GL-7ACA) acylase catalyzes the conversion of GL-7ACA to 7-amino cephalosporanic acid (7-ACA). The product 7-ACA is a starting compound for semi-synthetic cephalosporin antibiotics in industry. In order to detect the expression and specific activity of protein-engineered GL-7ACA acylase accurately, two useful detective systems for its expression has been established, in which reporter genes xylE and lacZ were fused to the downstream the GL-7ACA acylase gene acy respectively and the activity of catechol dioxygenase or beta-galactosidase could indicate the amount of acy expression.

Viscosity of Nonionic Polymer/Anionic Surfactant Complexes in Water

The polymer-micelle model, formerly established by Cabane, is revised to develop a new viscosity equation to describe the dependence of dilute solution viscosity on polymer concentration in PEG/SDS aqueous solutions. Two parameters inthe new equation were proposed to characterize the influence of the polymer solution viscosity on the added surfactant. The viscosity data of polyethylene glycol (PEG) solutions containing sodium dodecyl sulfate (SDS) were measured by the Ubbelohde dilution viscometer and the new equation proved to be in good agreement with the experimental data. Copyright 2000 Academic Press.

Expression in Escherichia coli, purification and kinetic analysis of the aspartokinase and aspartate semialdehyde dehydrogenase from the rifamycin SV-producing Amycolatopsis mediterranei U32

The operon encoding aspartokinase and aspartate semialdehyde dehydrogenase was cloned and sequenced from rifamycin-SV-producing Amycolatopsis mediterranei U32 previously. In the present work, these two genes were introduced into the auxotrophic Escherichia coli strain CGSC5074 (ask-) and E. coli X6118 (asd-), respectively. The A. mediterranei U32 asparto-kinase and aspartate semialdehyde dehydrogenase genes can be functionally expressed in E. coli and the gene products are able to substitute for the E. coli enzymes. Histidine-tagged aspartokinase and aspartate semialdehyde dehydrogenase were partially purified from E. coli cellular extracts and their kinetic characteristics were studied. Both aspartokinase and aspartate semialdehyde dehydrogenase showed typical Michaelis-Menten type substrate saturation patterns. Aspartokinase has Km values of 3.4 mM for aspartate and 2.3 mM for ATP, while aspartate semialdehyde dehydrogenase has Km values of 1.25 mM for DL-aspartate semialdehyde and 0.73 mM for NADP, respectively. Aspartokinase was inhibited by L-threonine, L-lysine, and L-methionine, but not by L-isoleucine and diaminopimelate. Aspartate semialdehyde dehydrogenase was not inhibited by any of the end-product amino acids at a concentration of less than 5 mM. Hill plot analysis suggested that asparto-kinase was subject to allosteric control by L-threonine. Repression of both aspartokinase and aspartate semi-aldehyde dehydrogenase gene transcription in A. mediterranei U32 by L-lysine, L-methionine, L-threonine, and L-isoleucine were found. The network of regulation of aspartokinase and aspartate semialdehyde dehydrogenase in rifamycin SV-producing A. mediterranei U32 is presented.

Isolation and characterization of a temperate bacteriophage from a ruminal acetogen

Nine acetogenic bacterial cultures recently isolated from the bovine rumen were tested for phage susceptibility by plaque formation. Both clear plaques and plaques with turbid centers were occasionally seen, but could not be used repeatedly to lyse pure cultures of acetogens, suggesting the possibility of a temperate phage. Five of the nine acetogenic isolates showed a response to mitomycin C induction. Acetogenic isolate H3HH was chosen for further study because it produced the greatest lysogenic response to mitomycin C. The bacteriophage was induced with mitomycin C, examined by transmission electron microscopy, and shown to have a hexagonal head (diameter, 59 eta m), a long flexible tail (192 eta m), and a flat collar (diameter, 31 eta m). The bacteriophage was classified within Bradley's group B. Bacteriophage DNA was determined to contain 36.2 kilobases of linear double-stranded DNA.

[Stress analysis for the abutments and the supporting alveolar bone in semi-fixed bridge]

This research was made in a mandibular that simulated dynamic relationship between occlusion,masticatory muscles and TMJ and that has full and normal teeth excepting the right second premolar was lost.This study measue\red and analysed the stress distribution and changing in the abutments and the supporting alveolar bone with strain gauge when the edentulous are was restored by T-type attachment and rest type connectors semifixed bridge.The results suggested that:(1)The stress of the abutment and alveolar bone increased by prematurity and it's distribution and changing were different according to the place of prematurity and type of the connectors.(2) T-type connecter has stress broken action and rest connector hasn't obvious such an action when prematurity of central occlusion.

Ontogeny of class II antigen expressing cells in rat incisor pulp

Class II antigen expressing cells are generally associated with the early phase of the immune response. Dendritic cells and macrophages expressing these cell surface antigens have recently been demonstrated and characterized in the dental pulp. The present study was undertaken to determine when the pulp receives its immunologic defense potential by examining the temporal appearance of class II antigen expressing cells in the rat incisor pulp. Pulp tissue specimens obtained at various time periods from a gestational age of 16 days to 14 wk after birth were examined by immunohistochemistry using O x 6 as a primary antibody and the ABC-technique. Comparisons were made with tissue samples from the spleen, intestine, skin and oral mucosa. At birth, all tissues, except for the pulp, presented cells expressing class II antigen with a dendritic appearance in a number and orientation resembling the mature tissue. A complete distribution of these cells was not seen in the dental pulp until 7 weeks following birth. Data show that the dental pulp acquires its ultimate structural arrangement of immune cells later than other tissues.