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.

Copper-Catalyzed Annulation of O-Acyl Oximes with Cyclic 1,3-Diones for the Synthesis of 7,8-Dihydroindolizin-5(6H)-ones and Cyclohexanone-Fused Furans

A copper-catalyzed annulation of O-acyl oximes with cyclic 1,3-diones has been developed for the concise synthesis of 7,8-dihydroindolizin-5(6H)-ones and cyclohexanone-fused furans through the substituent-controlled selective radical coupling process. 2-Alkyl cyclic 1,3-diones undergo C-C radical coupling, while 2-unsubstituted cyclic 1,3-diones undergo C-O radical coupling.

[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.

The actions of neonicotinoid insecticides on nicotinic acetylcholine subunits Ldα1 and Ldα8 of Leptinotarsa decemlineata and assembled receptors

The insect nicotinic acetylcholine receptor (nAChR) is a pentameric channel protein and also a target for neonicotinoids. There are few reported studies on the molecular interactions of Leptinotarsa decemlineata nAChRs with neonicotinoids. In this study, we analyzed the response of acetylcholine and neonicotinoids (thiamethoxam [TMX], imidacloprid [IMI], and clothianidin [CLO]) on hybrid receptors constructed by nAChR α1 and α8 subunits of L. decemlineata (Ldα1 and Ldα8) co-expressed with rat β2 subunit (rβ2) at different capped RNA (cRNA) ratios in Xenopus oocytes. In addition, we evaluated the expression changes of Ldα1 and Ldα8 after median lethal dose of TMX treatment for 72 h by quantitative polymerase chain reaction (qPCR). The resulting functional nAChRs Ldα1/rβ2 and Ldα1/Ldα8/rβ2 showed different pharmacological characteristics. The neonicotinoids tested showed lower agonist affinity on Ldα1/Ldα8/rβ2 compared to Ldα1/rβ2 at same ratios of subunit cRNAs. The sensitivities of neonicotinoids tested for Ldα1/rβ2 and Ldα1/Ldα8/rβ2 at cRNA ratios of 5:1, 1:1 and 5:5:1, 1:1:1, respectively, were lower than those for nAChRs at ratios of 1:5 and 1:1:5, respectively, whereas the values of maximum response (I_max ) varied. For Ldα1/Ldα8/rβ2, a reduction of Lda8 cRNA resulted in increased sensitivity to IMI and decreased sensitivity to TMX. The expression of Ldα1 and Ldα8 significantly decreased in adults by 82.12% and 47.02%, respectively, while Ldα8 was significantly upregulated by 2.44 times in 4th instar larvae after exposure to TMX. We infer that Ldα1 and Ldα8 together play an important role in the sensitivity of L. decemlineata to neonicotinoids.

[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.

[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.

Construction of hybrid DNAs@CP for the rapid synchronous sensing of multiplex microRNAs based on experimental studies and molecular simulation

A water stable one-dimensional (1D) ladder-shaped coordination polymer (CP) has been synthesized and exhibits a strong affinity to two fluorescein-tagged single-stranded probe DNAs (P-DNAs), giving a sensing platform of P-DNAs@1. Such a hybrid sensing platform is capable of simultaneous detection of breast cancer related microRNA-221 (miRNA-221) and miRNA-222 in a specific and synchronous manner, without observable cross-reactions, as supported by experimental evidences. The interaction mode and the electronic energy between CP 1 with nucleic acid were confirmed by molecular simulation and the universal force field (UFF).

[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.

Hsa_circ_0003998 may be used as a new biomarker for the diagnosis and prognosis of hepatocellular carcinoma

Background

Circular RNAs (circRNAs) play important roles in the progression of cancers, but the precise role of circRNAs in the diagnosis and prognosis of hepatocellular carcinoma (HCC) remains to be clarified. The aim of the current study was to explore the diagnostic and prognostic values of hsa_circ_0003998 in HCC.

Methods

CircRNAs expression was measured using RNA-seq analysis from HCC tissues (n=6) (three cases with or without portal vein invasion). Hsa_circ_0003998 in 200 pairs of HCC and adjacent noncancerous tissues and HCC cell lines was examined using qRT-PCR and the clinicopathologic significance was determined. We also detected the plasma levels of hsa_circ_0003998 in HCC, hepatitis B patients and healthy controls. The clinical diagnosis and prognostic values were further determined using receiver operating characteristic (ROC) curve, Kaplan–Meier curve and Cox regression.

Results

Hsa_circ_0003998 was upregulated in HCC tissues (P<0.001) and HCC cell lines (HepG2, HuH7, MHCC97H) (P<0.001). In addition, upregulation of hsa_circ_0003998 level was associated with higher serum alpha-fetoprotien (AFP) level (P=0.003), larger tumor diameter (P=0.009), lower differentiation level (P=0.023) and microvascular invasion (P=0.028). The plasma level of hsa_circ_0003998 in HCC patients was significantly higher than those in hepatitis B patients (P<0.001) and healthy controls (P<0.001). Its level was significantly reduced after the operation (P<0.001). The area under the ROC curve (AUC) for distinguishing HCC from adjacent noncancerous tissues was 0.894 (95% CI=0.86–0.922, P<0.001), the sensitivity and specificity were 0.84 and 0.8, respectively. Comparing with hepatitis B patients and healthy controls, hsa_circ_0003998, respectively, had an AUC value of 0.833 (95% CI=0.763–0.889, P<0.001) and 0.892 (95% CI=0.831–0.937, P<0.001). Their sensitivity and specificity were 0.83, 0.7 and 0.8, 0.84, respectively. Moreover, the combination of hsa_circ_0003998 and AFP showed the highest AUC value of 0.947, the sensitivity and specificity were 0.88 and 0.92, respectively. The hsa_circ_0003998 (P=0.003) and AFP (P=0.008) levels were independent prognostic factors for HCC. The overall survival of HCC patients with high level of hsa_circ_0003998 was significantly poorer than those with low level (P=0.005).

Conclusion

Our findings suggest that hsa_circ_0003998 may be used as a novel potential biomarker for the diagnosis and prognosis of HCC patients.

[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.

Germline mutations in 40 cancer susceptibility genes among Chinese patients with high hereditary risk breast cancer

Multigene panel testing of breast cancer predisposition genes have been extensively conducted in Europe and America, which is relatively rare in Asia however. In this study, we assessed the frequency of germline mutations in 40 cancer predisposition genes, including BRCA1 and BRCA2, among a large cohort of Chinese patients with high hereditary risk of BC. From 2015 to 2016, consecutive BC patients from 26 centers of China with high hereditary risk were recruited (n = 937). Clinical information was collected and next-generation sequencing (NGS) was performed using blood samples of participants to identify germline mutations. In total, we acquired 223 patients with putative germline mutations, including 159 in BRCA1/2, 61 in 15 other BC susceptibility genes and 3 in both BRCA1/2 and non-BRCA1/2 gene. Major mutant non-BRCA1/2 genes were TP53 (n = 18), PALB2 (n = 11), CHEK2 (n = 6), ATM (n = 6) and BARD1 (n = 5). No factors predicted pathologic mutations in non-BRCA1/2 genes when treated as a whole. TP53 mutations were associated with HER-2 positive BC and younger age at diagnosis; and CHEK2 and PALB2 mutations were enriched in patients with luminal BC. Among high hereditary risk Chinese BC patients, 23.8% contained germline mutations, including 6.8% in non-BRCA1/2 genes. TP53 and PALB2 had a relatively high mutation rate (1.9 and 1.2%). Although no factors predicted for detrimental mutations in non-BRCA1/2 genes, some clinical features were associated with mutations of several particular genes.

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.

CBX6 overexpression contributes to tumor progression and is predictive of a poor prognosis in hepatocellular carcinoma

Aberrant chromobox (CBX) family protein expression has been reported in a variety of human malignancies. However, the role of CBX6 in hepatocellular carcinoma (HCC) progression and patient prognosis remains unknown. In this study, we found that CBX6 was frequently up-regulated in HCC clinical samples and HCC cell lines and that CBX6 expression was significantly correlated with larger tumor sizes (≥ 5 cm, p = 0.011) and multiple tumors (n ≥ 2, p = 0.018). Survival analyses indicated that patients with higher CBX6 expression levels had significantly shorter recurrence-free survival (RFS) and overall survival (OS) than patients with lower CBX6 expression levels, and multivariate analyses confirmed that increased CBX6 expression was an independent unfavorable prognostic factor for HCC patients. Functional study demonstrated that CBX6 profoundly promoted HCC cell growth both in vitro and in vivo, and mechanistic investigation revealed that the S100A9/NF-κB/MAPK pathway was essential for mediating CBX6 function. In conclusion, our results represent the first evidence that CBX6 contributes to tumor progression and indicate that the protein may serve as a novel prognostic biomarker for HCC and as a therapeutic target in the treatment of the disease.

[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.

KRT8 upregulation promotes tumor metastasis and is predictive of a poor prognosis in clear cell renal cell carcinoma

Keratin 8 (KRT8) plays an essential role in the development and metastasis of multiple human cancers. However, its role in clear cell renal cell carcinoma (ccRCC) remains unexplored. Here, we investigated the expression pattern, clinical significance, and function of KRT8 in ccRCC. KRT8 mRNA and protein levels were determined in two large cohorts using quantitative real-time polymerase chain reaction (qRT-PCR) and tissue microarray (TMA) immunohistochemistry (IHC), respectively. We found that KRT8 expression was upregulated in ccRCC and vein tumor thrombi (VTTs). KRT8 overexpression in ccRCC was significantly correlated with aggressive characteristics and was predictive of a poor prognosis in ccRCC patients. Moreover, KRT8 overexpression in renal cancer cell lines promoted cell migration and invasion. In contrast, KRT8 knockdown suppressed ccRCC metastasis both in vitro and in vivo. In addition, our findings showed that KRT8 promoted ccRCC metastasis by increasing IL-11 expression, causing IL-11 autocrine induction, and triggering STAT3 signaling. Overall, this study established the significance of KRT8-IL-11 axis activation in aggressive ccRCC and defined a novel critical signaling mechanism that drives human ccRCC invasion and metastasis.

TMED3 promotes hepatocellular carcinoma progression via IL-11/STAT3 signaling

Transmembrane p24 trafficking protein 3(TMED3) is a metastatic suppressor in colon cancer, but its function in the progression of hepatocellular carcinoma (HCC) is unknown. Here, we report that TMED3 was up-regulated in HCC and portal vein tumor thrombus. TMED3 up-regulation in HCC was significantly correlated with aggressive characteristics and predicted poor prognosis in HCC patients. TMED3 overexpression in HCC cell lines promoted cell migration and invasion. In contrast, TMED3 knockdown suppressed HCC metastasis both in vitro and in vivo. Gene microarray analysis revealed decreased IL-11 expression in TMED3-knockdown cells. We propose that TMED3 promotes HCC metastasis through IL-11/STAT3 signaling. Taken together, these findings demonstrate that TMED3 promotes HCC metastasis and is a potential prognostic biomarker in HCC.

Prognostic significance of circulating tumor cells in esophageal carcinoma: a meta-analysis

PURPOSE

The prognostic significance of circulating tumor cells (CTCs) in esophageal carcinoma (EC) is controversial. We aim to assess its association with clinicopathological and prognostic relevance in EC by using a meta-analysis.

METHODS

We searched PubMed, Cochrane Database, Embase databases, and the references in relevant studies that assessed the clinicopathological or prognostic relevance of CTCs in peripheral blood of patients with EC. Statistical analyses were conducted by using Stata software to calculate the pooled odds ratio (OR), hazard ratio (HR), and 95% confidence intervals (CIs) using fixed or random-effects models according to the heterogeneity of included studies. The subgroup analyses were performed according to ethnicity, histological type, and detection method.

RESULTS

Sixteen trials containing 1,260 patients were included for analysis. Pooled results showed that presence of CTCs was significantly associated with poor overall survival (HR =1.71, 95% CI [1.30, 2.12], P<0.001) and progression-free survival (HR =1.67, 95% CI [1.19, 2.15], P<0.001) in EC patients. Subgroup analysis indicated that presence of CTCs was closely associated with worse overall survival (Asian: HR =1.66, 95% CI [1.24, 2.08], P<0.001; squamous cell carcinoma [SCC]: HR =1.66, 95% CI [1.24, 2.08], P<0.001; no polymerase chain reaction [PCR]: HR =2.08, 95% CI [1.40, 2.76], P<0.001) and progression-free survival (Asian: HR =1.63, 95% CI [1.15, 2.12], P<0.001; SCC: HR =1.63, 95% CI [1.15, 2.12], P<0.001; PCR: HR =1.63, 95% CI [1.15, 2.12], P<0.001). Additionally, ORs showed that presence of CTCs was significantly correlated with tumor node metastasis (TNM) staging (overall: OR = 1.96, 95% CI [1.34, 2.87], P=0.001; Asian: OR =2.09, 95% CI [1.37, 3.19], P=0.001; SCC: OR =1.97, 95% CI [1.21, 3.07], P=0.003; PCR: OR =2.23, 95% CI [1.43, 3.47], P<0.001), venous invasion (overall: OR =2.23, 95% CI [1.46, 3.40], P<0.001; Asian: OR =2.23, 95% CI [1.46, 3.40], P<0.001; SCC: OR =2.23, 95% CI [1.46, 3.40], P<0.001; PCR: OR =2.23, 95% CI [1.46, 3.40], P<0.001), lymph node metastasis (overall: OR =2.41, 95% CI [1.50, 3.86], P<0.001; Asian: OR =2.89, 95% CI [1.80, 4.65], P<0.001; SCC: OR =2.44, 95% CI [1.47, 4.07], P=0.001; PCR: OR =2.89, 95% CI [1.80, 4.65], P<0.001) and distant metastasis (Asian: OR =2.68, 95% CI [1.01, 7.08], P=0.047) in patients with EC.

CONCLUSION

The presence of CTCs indicates a poor prognosis in EC patients, especially in Asian and SCC patients. Further well-designed prospective studies are recommended to explore the clinical applications of CTCs in patients with EC.

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.

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.

Chlorantraniliprole susceptibility in Leptinotarsa decemlineata in the north Xinjiang Uygur autonomous region in China

The Colorado potato beetle (Leptinotarsa decemlineata (Say)) in the north Xinjiang Uygur autonomous region has evolved resistance to various types of insecticides. Chlorantraniliprole is a novel anthranilic diamide insecticide that binds and activates ryanodine receptors. It exhibited excellent efficacy against L. decemlineata in several field trails in Europe. In the present paper, the susceptibility of L. decemlineata fourth-instar larvae derived from six field populations and L. decemlineata adults derived from three field populations to chlorantraniliprole was determined by a topical application. The fourth-instar larvae were substantially more susceptible to chlorantraniliprole than adults, although the range of susceptibility was far greater among the fourth-instar larvae. Regarding stomach toxicities, adult beetles were less susceptible to chlorantraniliprole than larvae. Chlorantraniliprole was most toxic to second-instar larvae, followed by third- and fourth-instar larvae. These data suggested that the appropriate timing for chlorantraniliprole spraying is the early larval stage. Moreover, the synergistic activities of chlorantraniliprole in combination with triphenyl phosphate, diethyl maleate, or piperonyl butoxide against fourth-instar larvae from two field populations and adults from one field population were tested. Piperonyl butoxide had synergistic effects with chlorantraniliprole against fourth-instar larvae but not against adult beetles. Conversely, triphenyl phosphate and diethyl maleate exerted little synergistic effects. It appears that there is a potential risk of resistance against chlorantraniliprole resulting from cytochrome P450 monooxygenase activity.

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.

Insecticide resistance status of Colorado potato beetle (Coleoptera: Chrysomelidae) adults in northern Xinjiang Uygur autonomous region

Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), has become the economically most important insect defoliator of potatoes, Solanum tuberosum L., in northern Xinjiang Uygur autonomous region in China. Currently, control of Colorado potato beetle relies mainly on chemical insecticides. And this may result in insecticide resistance. In this study, LD50 values were measured by a topical bioassay for 14 conventional insecticides in seven local populations from Urumqi, Changji, Tacheng, Nilka, Gongliu, Qapqal, and Tekes counties (cities). The Tekes field population was the most susceptible population and was selected as a reference strain. Compared with the Tekes strain, the Changji, Qapqal, Nilka, Tacheng, and Gongliu populations exhibited moderate to very high levels of resistance to cyhalothrin. The Qapqal and Changji populations showed a moderate and a very high resistance to deltamethrin, respectively. And the Changji population developed a high resistance against alpha-cypermethrin. Moreover, the Qapqal population had a moderate resistance to carbofuran, and the Urumqi population reached high level of resistance to endosulfan. Possible resistance mechanisms of the Changji and Qapqal populations were determined using three enzyme inhibitors. Triphenyl phosphate (TPP), diethylmeleate, and piperonyl butoxide (PBO) had little synergism to cyhalothrin in the two populations. In contrast, PBO and TPP exhibited some synergistic effects to carbofuran in the Qapqal population, indicating the involvement of monooxygenases and esterases in conferring carbofuran resistance. It seems that additional mechanisms, such as target site insensitivity, should play an important role in Colorado potato beetle resistances to cyhalothrin and carbofuran in northern Xinjiang local populations.

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.

[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.

Interaction between cholinergic neurons and substance P or calcitonin gene-related peptide terminals of the rat sacral intermediolateral nucleus: double immunostaining at the light and electron microscopic levels

The relationships both between cholinergic neurons and substance P (SP) and between cholinergic neurons and calcitonin gene-related peptide (CGRP) terminals were examined in the rat sacral intermediolateral nucleus at the light and electron microscopic levels by means of double-immunostaining methods. Cholinergic neurons were labeled by a monoclonal antibody to choline acetyltransferase (CAT) with the avidin-biotin technique and stained bluish-green by indolyl-beta-galactoside reaction products with beta-galactosidase as a marker. On the same sections, SP or CGRP fibers were labeled by polyclonal antisera to SP or CGRP after application of the peroxidase-antiperoxidase (PAP) method and stained brown by the p-dimethylaminoazobenzene (DAB) reaction. After embedding in Epon, light and electron microscopic sections were examined. At the light microscopic level, CGRP-like immunoreactive (CGRP-I) fibers and SP-like immunoreactive (SP-I) fibers were found to pass through the lateral edge of the dorsal horn and then into the dorsal region of the sacral intermediolateral nucleus. In addition, SP-I fibers also extend from the dorsolateral funiculus into the entire sacral intermediolateral region. At the electron microscopic level, many axosomatic and axodendritic synapses were found between CAT-I structures and SP-I terminals in the intermediolateral nucleus, whereas most of the CGRP-I terminals in this area made axodendritic synapses with CAT-I dendrites. These results indicate that cholinergic neurons in the sacral intermediolateral nucleus receive direct synaptic input from SP-I and CGRP-I terminals.(ABSTRACT TRUNCATED AT 250 WORDS)