Dosage selection and effect evaluation of sodium pentobarbital in tree shrew anesthesia.

To achieve surgical anesthesia in animal experimentation, it is important to select the appropriate anesthetic dose. However, few studies have investigated the reasonable anesthetic dose in tree shrew (Tupaia belangeri). The aim of the study was to review the literature to determine the most commonly used anesthetic dose in tree shrew and to calculate the reasonable equivalent dose between tree shrew and rat based on the body surface area conversion. Two groups of 10 adult tree shrews each were anesthetized with 1% sodium pentobarbital through intraperitoneal injection separately at doses of 62 mg/kg (equivalent dose) and 40 mg/kg (reported dose). Anesthetic depth and times were assessed in addition to vital signs. The results showed that the dosage was quite different across studies, ranging from 15 mg/kg to 80 mg/kg, with 40 mg/kg being the most frequently reported dose. However, the group of tree shrews anesthetized with the commonly reported dose were unable to meet the requirements of surgery. In contrast, the equivalent dose (62 mg/kg, intraperitoneal injection with sodium pentobarbital) calculated by body surface area conversion could achieve an anesthetic time of 44.28 ± 3.95 min with no serious or fatal effects. During anesthetic monitoring, we found that sodium pentobarbital had an inhibitory effect on the blood pressure, pulse rate, respiratory rate and rectal temperature in tree shrews, especially on the respiratory rate. Thus, our study indicated that the use of the equivalent dose of sodium pentobarbital was effective in anesthetizing tree shrews.

Preoperative evaluation of cochlear implantation through the round window membrane in the facial recess using high-resolution computed tomography.

PURPOSE: We evaluated the risk of cochlear implantation through the round window membrane in the facial recess through a preoperative analysis of the angle between the facial nerve-round window and the cranial midline using high-resolution temporal bone CT. METHODS: Temporal bone CT films of 176 patients with profound sensorineural hearing loss at our hospital from 2013 to 2015 were reviewed. The preoperative temporal bone CT scans of the patients were retrospectively analysed. The vertical distance (d value) from the leading edge of the facial nerve to the posterior wall of the external auditory canal and the angle (α value) between the line from the leading edge of the facial nerve to the midpoint of the round window membrane and the median sagittal line on the round window membrane plane were measured. Based on intraoperative observation, the round window membrane was divided into complete round window membrane exposure (group A), partial exposure (group B), and unexposed (group C) groups, and statistical analysis was performed. RESULTS: The α value could be effectively measured for all 176 patients (62.60 ± 7.12), and the d value could be effectively measured for 95 cases (5.53 ± 1.00). An analysis of the correlation between the α and d values of these 95 cases found a negative correlation. Of the 176 cases, one-way analysis of variance (ANOVA) showed that the differences among the groups were significant [P = 0.000 (< 0.05)]. CONCLUSION: The angle (α value) between the line connecting the leading edge of the facial nerve to the midpoint of the round window and the median sagittal line measured in preoperative CT scans was associated with the difficulty of intraoperatively exposing the round window membrane. When the α value was larger than a certain degree, the difficulty of exposing the round window membrane was increased. In such cases, the surgeon should fully expose the round window membrane during surgery, which could result decrease the likelihood of complications.

Effect of Y6, an epigallocatechin gallate derivative, on reversing doxorubicin drug resistance in human hepatocellular carcinoma cells.

Cancer cells can acquire resistance to a wide variety of diverse and unrelated drugs, this phenomenon is termed multidrug resistance (MDR). Multidrug resistance has been an obstacle to the success of cancer chemotherapy. The present study investigated the reversal effect of Y6, a new compound obtained by chemically modifying the structure of epigallocatechin-3-gallate (EGCG) extracted from green tea. Y6 was proven to be effective in inhibiting cell proliferation and reversing drug resistance in doxorubicin (DOX) resistant human hepatocellular carcinoma cells (BEL-7404/DOX). BEL-7404/DOX cells were treated with either doxorubicin combination regimen (doxorubicin plus Y6 or epigallocatechin-3-gallate or verapamil separately) or doxorubicin alone. The results showed that cell proliferation was inhibited and late cell apoptosis increased in the combination treatment group, especially in the group treated with doxorubicin plus Y6. Further analysis revealed that the expressions of hypoxia-inducible factor-1α and multidrug resistance 1/P-glycoprotein decreased at both messenger RNA and protein levels by treatments with combined drugs compared to doxorubicin alone. Our results indicated that Y6, as a drug resistance reversal agent, increased the sensitivity of drug resistant cells to doxorubicin. The mechanisms of actions of Y6 in reversal effect were associated with the decreased expression of hypoxia-inducible factor-1α and multidrug resistance 1/P-glycoprotein.

Electrophysiological change in the tensor veli palatini muscle after radiotherapy.

CONCLUSION: Electromyography of the tensor veli palatine (TVP) was abnormal and showed mainly myogenic impairment in patients with nasopharyngeal carcinoma (NPC) with secretory otitis media (SOM) after radiotherapy. The diseased ears showed impairment in opening functions of the eustachian tubes (ETs). OBJECTIVES: To characterize electrophysiology of the TVP muscle using electromyography (EMG) in patients with SOM after radiotherapy of NPC. METHODS: Twenty healthy volunteers and 20 patients with NPC and SOM after radiotherapy were chosen for assessment of EMG of the TVP during swallowing. RESULTS: The measurements of average duration and amplitude of action potential, swallowing contraction duration, and peak voltage in NPC patients with both SOM (n = 25) and healthy ears (n = 6) were significantly lower than those of ears (n = 38) in healthy controls (p < 0.01). In patients with NPC, the average action potential duration and swallowing contraction duration in ears with SOM were lower than those of subjects with healthy ears (p < 0.05), whereas no significant difference was found in average amplitude of action potential and peak voltage between them.

[Research on the effect of biyan qingdu granula drug-containing serum on inhibition of nasopharyngeal carcinoma cells growth in vitro].

OBJECTIVE: To investigate the effect of Biyan Qingdu Granula drug-containing serum (BQG-DS) on cell growth and apoptosis in nasopharyngeal carcinoma cell lines CNE1, CNE2, TWO3, C666-1, and explore the antineoplastic mechanism of Biyan Qingdu Granula. METHODS: SD rats were randomly divided into three groups: experimental (Biyan Qingdu Granula) group, positive control (cytoxan) group and negative control group. After administration of drug, the serum was collected from the treated animals. MTT assay was used to examine the effect of BQG-DS on the proliferation of CNE1, CNE2, TWO3, C666-1 cell, and flow cytometry was used to observe the cell cycle distribution. Apoptosis of CNE1, CNE2, TWO3, C666-1 cell was further investigated by inverted microscope. RESULTS: BQG-DS inhibited the proliferation of CNE1, CNE2, TWO3, C666-1 cell and the effects were in a time-and concentration-dependent manner. BQG-DS could also induce apoptosis while the G1 phase was arrested. CONCLUSION: BQG-DS inhibits proliferation of nasopharyngeal carcinoma cells via induction of apoptosis and arrest of cell cycle.

[Inner ear morphological study of guinea pigs with acoustically evoked short latency negative response].

OBJECTIVE: To establish a model of ototoxicity in guinea pigs with acoustically evoked short latency negative response (ASNR) and verify the responsible organ of ASNR based on microscopic characteristics of basal membranes, saccules, utricles and ampulla canalis semicircularis of the inner ear. METHODS: Total of 45 guinea pigs were employed in the experiment, which were randomly divided into the control group (15 subjects, 30 ears) and the deafened group (30 subjects, 60 ears). Each animal experienced auditory brainstem response (ABR). A quick treatment was employed for deafened group consisting of a subcutaneous injection of kanamycin at a dose of 400 mg/kg followed by jugular vein injection of ethacrynic acid at a dose of 40 mg/kg one hour later. The animals were performed ABR test from 7 to 10 days after the drug administration. The deafened group was further divided into ASNR group and non-ASNR group based on the presence of ASNR. All the guinea pigs were sacrificed after ABR tests. The Corti organ, macula sacculi, macula utriculi and crista ampullaris were observed by light microscope. RESULTS: In the deafened group (60 ears), 3 subjects died postoperatively, 27 subjects (54 ears) provided full data. ASNR was elicited in 19 ears (35.2%, 19/54), the thresholds of ASNR were from 110 to 125 dBSPL with average of (121.7 ± 4.5) dBSPL. ASNR latency ranges were 1.80 - 2.08 ms, the average latency of thresholds were (1.93 ± 0.07) ms. The stretched preparation results: overall hair-cell density of macula saccule, macula utriculi and crista ampullaris decreased in order of normal control group, ASNR group and non-ASNR group. There was no difference between the normal group and ASNR group for cell density of macula saccule. Apart from this, statistical differences were found among other groups. CONCLUSIONS: The present study evoked ASNR in an ototoxicity guinea pig model which was profound hearing loss with normal saccular function and normal saccular hair cell density. It suggested that ASNR originates from the saccule and have no relation with cochlear, utricle and semicircular canal according to morphological study.

[Protective effects of N-acetylcysteine on cochlear damage occur in guinea pigs exposed to irradiation].

OBJECTIVE: To explore the protective effects of N-acetylcysteine (NAC) on cochlear damage occurring in irradiated guinea pigs. METHODS: Seventy-two guinea pigs were randomly divided into 4 groups (n = 18 each). Control group received neither NAC nor irradiation, irradiation group received total cranium irradiation of 70 Gy, irradiation & saline group cranium irradiation of 70 Gy and saline solution through a round window and NAC group cranium irradiation of 70 Gy and NAC through a round window. The right ear received radiation. The animals were sacrificed at Day 14 post-irradiation. The specimens were dehydrated, embeded in paraffin and serially cut into 5-µm slices. Sections were stained with immunohistochemistry and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL). The cochlear basal membranes were observed for malondialdehyde (MDA) and superoxide dismutase (SOD) with scanning electron microscope. RESULTS: The cilium of hair cells had no clear loss and apoptotic number of spiral ganglion cells decreased in NAC group. The average optical density value of Caspase 3 in spiral ganglion in NAC group significantly decreased versus the irradiation group (0.08 ± 0.02 vs 0.10 ± 0.01, P < 0.01). The level of MDA of NAC group also decreased versus the irradiation group (0.33 ± 0.05 vs 0.84 ± 0.13, P < 0.05). The level of SOD in the NAC group increased versus the irradiation group (10.7 ± 3.0 vs 8.7 ± 1.3, P < 0.05). The ratio of apoptotic cell in SGC in the NAC group at Day 14 (7.8% ± 1.8%) decreased versus the irradiation group (32.0% ± 8.7%) at Day 14. CONCLUSION: MDA and SOD may be involved in the pathogenesis of cochlear cell damage. And NAC protects the irradiated cochlear cell.

[Analysis of sniffing test in otitis media with effusion].

OBJECTIVE: To explore the roles of the closure disorder of Eustachian tube in occurrence and development of otitis media with effusion (OME). METHODS: Fifty-six adults with OME, 16 children with OME, 66 health adults and 20 health children were selected according to diagnosis criteria. Sniffing test was measured by Tubo-tymanoaerodynamic graphy and the self-designed questionnaires were surveyed in all cases. RESULTS: The positive levels in sniffing test were regarded as external auditory canal press 10dapa lower than baseline of the pressure. The positive rate was 64.86% in adults with OME, which was higher than health adults (P < 0.01). The positive rate was 70.83% in children with OME which was higher than health children (P < 0.05). CONCLUSIONS: The higher positive rate of sniff test in OME patients suggests that closure disorder in Eustachian tube playing an important role in the occurrence and development of OME.

[Reversal effect of matrine on drug resistance of human nasopharyngeal carcinoma cell line].

OBJECTIVE: To study the reversal effect of matrine and its derivatives on drug resistance of human nasopharyngeal carcinoma cell line HONE1/DDP. METHODS: The drug-resistant cell line was established by the human nasopharyngeal carcinoma cells HONE1 with gradually increasing concentration of cisplatin. The matrine and its derivatives were added into the HONE1/DDP according to different concentrations to measure their cytotoxicity. MTT assay was used to measure the reversal effect on the drug resistance of the non-toxic doses of matrine and its derivatives. Cell cycle was measured by flow cytomety. The expression level of MRP1, BAX, BCL-2 was assayed by Western blot. RESULTS: HONE1/DDP indicated drug resistantance. When the non-toxic doses of matrine and its derivatives were used to HONE1/DDP with 24h, the resistance of HONE1/DDP was down-regulated, the reversal fold was 1.45 and 1.77. The cell number of G0/G1-phase increased in matrine group while S phase decreased in matrine derivatives group compared with HONE1/DDP. Compared with HONE1/DDP group, the MRP1 expression levels in HONE1 cells were reduced (P < 0.05), and Matrine group and matrine derivatives group were enhanced (P < 0.05). The expression of BAX was lower while the expression of BCL-2 was higher. CONCLUSION: The resistance of HONE1 cells to DDP is able to increase the expression of MRP1; Matrine and its derivatives can reverse the drug resistance of HONE1/DDP to DDP, its activity may be related to change cell cycle distribution, the inhibition of MRP1 expression and down-regulation of BAX/BCL-2.

[Clinical analyses of sudden sensorineural hearing loss in 14 nasopharyngeal carcinomas following radiotherapy].

OBJECTIVE: To investigate the clinical characteristics and effects of sudden sensorineural hearing loss in nasopharyngeal carcinoma (NPC) following radiotherapy. METHODS: The clinical characteristics and effects in 14 NPC patients (15 ears) with sudden sensorineural hearing loss following radiotherapy were retrospectively analyzed. RESULTS: The sudden sensorineural hearing loss happened more in male subjects than female subjects and more in the left ear than the right ear. Its occurrence time was averaged 6.6 years following radiotherapy. Most of the patients suffered hearing loss prior to the sudden sensorineural hearing loss. The 250, 500, 1000, 2000, 4000 Hz average hearing thresholds: sudden hearing loss ears (78.5 ± 24.7) dBHL, none-sudden hearing loss ears (57.0 ± 32.4) dBHL, among which, 73.33% (11/15) for sensorineural hearing loss, 26.67% (4/15) for mixed hearing loss. 12 cases had complications following radiotherapy. At least one case had posterior circulation barrier. The total effective rate was 26.67% (4/15) and four cases had relapsed and in vain thereafter. CONCLUSIONS: In NPC patients who received radiotherapy, it caused more serious sudden sensorineural hearing loss and the treatment effects were poor and hearing loss was susceptible to relapse. The pathogenesis may be related to the radiation caused posterior circulation disorders.

[Origin of acoustically evoked short latency negative response in guinea pigs].

OBJECTIVE: To establish a model of acoustically evoked short latency negative response (ASNR) in guinea pigs, a model of profound hearing loss with normal saccular functions, and verify the correlation between ASNR and vestibular evoked myogenic potential (VEMP). METHODS: Thirty-two healthy guinea pigs were employed in the experiment, which were randomly divided into control group (16 subjects) and deafened group (16 subjects). Each animal experienced auditory and vestibular tests including auditory brainstem response (ABR), VEMP and caloric test. A quick treatment was employed for deafened group consisting of a subcutaneous injection of kanamycin at a dose of 400 mg/kg followed by a jugular vein injection of ethacrynic acid at a dose of 40 mg/kg one hour later. The animals were received ABR, VEMP and caloric test 7 - 10 days following the drug administration. The deafened group was further divided into ASNR group and non-ASNR group, based on the presence of ASNR. RESULTS: In deafened group, five subjects died postoperatively, 11 subjects (22 ears) provided full data, ASNR was elicited in eight ears (36.4%), the threshold was 120 - 130 dB SPL with mean of (124.4 ± 4.96) dB SPL. Its latency range was 1.75 - 2.60 ms with mean of (2.15 ± 0.27) ms. The mean latency of threshold was (2.34 ± 0.18) ms. All eight ASNR ears presented with VEMP. The VEMP threshold, positive and negative potential latencies proved no statistical difference (P > 0.05) between ASNR group and control group. Significant difference was detected between the VEMP presence of ASNR group and non-ASNR group (P = 0.002). There was no statistically significant correlation between VEMP and caloric test neither between ASNR and caloric test in deafened group. CONCLUSIONS: This study evoked ASNR in an ototoxicity guinea pig model which has profound hearing loss with normal saccular functions. The presence of ASNR correlated with VEMP, however, not correlated with caloric test, suggesting that ASNR and VEMP are both originated from the saccule.

Blocking caspase-3-dependent pathway preserves hair cells from salicylate-induced apoptosis in the guinea pig cochlea.

In the present study, we aim to explore whether the caspase-3-dependent pathway is involved in the apoptotic cell death that occurs in the hair cells (HCs) of guinea pig cochlea following a salicylate treatment. Guinea pigs received sodium salicylate (Na-SA), at a dose of 200 mg·kg(-1)·d(-1) i.p., as a vehicle for 5 consecutive days. In some experiments, N-benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone (zDEVD-FMK), a specific apoptosis inhibitor, was directly applied into the cochlea via the round window niche (RWN) prior to salicylate treatment for determination of caspase-3 activation. Alterations in auditory function were evaluated with auditory brainstem responses (ABR) thresholds. Caspase-3 activity was determined by measuring the proteolytic cleavage product of caspase-3 (N-terminated peptide substrate). DNA fragmentation within the nuclei was examined with a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method. Ultrastructure variation in the target cell was assessed by electron microscopy (EM). Salicylate treatment initiated an obvious elevation in ABR thresholds with a maximum average shift of 60 dB sound pressure level (SPL), and caused significant apoptosis in both inner (IHCs) and outer (OHCs) hair cells resulted from an evident increasing in immunoreactivity to caspase-3 protease. Transmission electron microscopy (TEM) displayed chromatin condensation and nucleus margination accompanied by cell body shrinkage in the OHCs, but not in the IHCs. Scanning electron microscopy (SEM) showed breakdown, fusion, and loss in the stereociliary bundles at the apex of OHCs rather than IHCs. zDEVD-FMK pretreatment prior to salicylate injection substantially attenuated an expression of the apoptotic protease and protected HCs against apoptotic death, followed by a moderate relief in the thresholds of ABR, an alleviation in the submicroscopic structure was also identified. In particular, disorientation and insertion in the hair bundles at the apex of OHCs was exhibited though no classic apoptotic change found. The above changes were either prevented or significantly attenuated by zDEVD-FMK. These findings indicate that salicylate could damage cochlear hair cells via inducing apoptosis associated with caspase-3 activation.

Nitrative and oxidative DNA damage as potential survival biomarkers for nasopharyngeal carcinoma.

Currently, there are no satisfactory biomarkers available to screen for nasopharyngeal carcinoma (NPC). Nitric oxide (NO), produced by inducible nitric oxide synthase (iNOS), has been suggested to cause nitrative and oxidative stress, leading to the accumulation of 8-nitroguanine (8-NitroG) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the subsequent transversion mutation of DNA. The aim of this study was to evaluate iNOS expression and the status of nitrative and oxidative stress in NPC. Fifty-nine cases of NPC and 39 cases of chronic nasopharyngitis were investigated to examine the expression of iNOS and the formation of 8-NitroG and 8-OHdG, using double-immunofluorescent staining. The statistical differences in immunoreactivities were analyzed using the Mann-Whitney test. Thirty-six patients from the 57 cases of NPC and 36 healthy controls were investigated to examine the level of serum 8-OHdG, using enzyme-linked immunosorbent assay (ELISA). The statistical differences were analyzed using a t test. Strong DNA lesions were observed in the cancer cells of NPC patients. All cases of NPC were positive for 8-NitroG and 8-OHdG, and 54 (94.7%) were positive for iNOS. NPC samples exhibited significantly more intense staining for 8-NitroG, 8-OHdG and iNOS than those of chronic nasopharyngitis (P < 0.05, respectively). The mean value of serum 8-OHdG in the 36 NPC patients was 0.538 ± 0.336 ng/ml compared to 0.069 ± 0.059 ng/ml for the healthy controls. The difference in the serum levels of 8-OHdG between the NPC patients and controls was statistically significant (P < 0.05). Our present findings suggest that pathological stimulation of nasopharyngeal tissue, caused by bacterial, viral or parasitic inflammation, may lead to nitrative and oxidative DNA lesions, caused by NO. This may contribute to the cause and development of NPC. Thus, 8-NitroG and 8-OHdG could be potential biomarkers for evaluating the risk of NPC. Better understanding of the molecular mechanisms underlying nitrative and oxidative DNA damage may provide clues to molecular targets for new approaches of NPC prevention.

Analysis of Epstein-Barr viral DNA load, EBV-LMP2 specific cytotoxic T-lymphocytes and levels of CD4+CD25+ T cells in patients with nasopharyngeal carcinomas positive for IgA antibody to EBV viral capsid antigen.

BACKGROUND: Epstein-Barr virus (EBV) is a herpesvirus commonly associated with several malignant diseases including nasopharyngeal carcinoma (NPC), which is a common cancer in Southeastern Asia. Previous studies showed that plasma levels of EBV-DNA might be a sensitive and reliable biomarker for the diagnosis, staging and evaluating of therapy for NPC. There are a few analyses of the levels of EBV-latent membrane protein 2 (LMP2)-specific cytotoxic T-lymphocytes (CTLs) in patients with NPC. This study was conducted to investigate the levels of EBV-LMP2-specific CTLs, EBV-DNA load and the level of CD4(+)CD25(+) T cells in such patients. METHODS: From February 2006 to April 2006, 62 patients with NPC, 40 healthy virus carriers positive for EBV viral capsid antigen (EBV-IgA-VCA) and 40 controls were enrolled in the study. We used a highly sensitive ELISPOT assay, real-time polymerase chain reaction (PCR) and flow cytometry to measure the EBV-LMP2-specific CTL response, the EBV DNA load and the level of CD4(+)CD25(+) T cells, respectively. RESULTS: The EBV-LMP2-specific CTL responses of the samples from the control, healthy virus carriers and patients with NPC were significantly different from the LMP2 epitopes, with the control and healthy virus carrier samples displaying a stronger response in three cases. There were significant differences in EBV DNA load in serum between NPC and the healthy groups; patients with NPC at stages III or IV had significantly higher viral loads compared with those at stages I or II. A significantly higher percentage of CD4(+)CD25(+) T lymphocytes were detected in the patients, compared with healthy virus carriers and healthy controls. Moreover, patients with advanced stages of NPC (III and IV) had significantly higher percentages than the patients with early stages (I and II). CONCLUSIONS: Patients with NPC are frequently unable to establish or maintain sufficient immunosurveillance to control proliferating B cells harboring EBV and to destroy the tumor cells that express immunodominant LMP2 proteins. Controlling the activity of CD4(+)CD25(+) T cells and elevating CD8(+) cells specific for LMP2 epitopes could be an effective immunotherapy for patients with NPC.

Bacteriology of postradiotherapy chronic rhinosinusitis in nasopharyngeal carcinoma patients and chronic rhinosinusitis.

The purpose of this study was to investigate and compare the bacteriology of postradiotherapy chronic rhinosinusitis (postRT-CRS) and chronic rhinosinusitis (CRS) by evaluating the aspiration materials of the maxillary sinus of patients with postRT-CRS and patients with CRS. We collected the secretions of the maxillary sinus from 30 nasopharyngeal carcinoma patients with postRT-CRS and 30 patients with CRS for aerobe/facultative anaerobe bacteria culture. The most common isolates in the postRT-CRS group were Streptococcus viridans, Staphylococcus aureus and Haemophilus influenzae, while those in the CRS group were Haemophilus influenzae, Pseudomonas aeruginosa and Staphylococcus aureus. Isolated gram-positive coccus rate in postRT-CRS patients was significantly higher than in CRS patients (62.50% compared with 30.00%, respectively; P < 0.05), and isolated gram-negative bacilli rate in postRT-CRS patients was significantly lower than in CRS patients (31.25% compared with 70.00%, respectively; P < 0.05). However, the incidence of positive cultures was not significantly different between the postRT-CRS group and the CRS group (P > 0.05). This study found that there were some differences in bacteriology between postRT-CRS and CRS. Gram-positive coccus was the predominant aerobic/facultative anaerobe pathogenic bacterium in patients with postRT-CRS, and gram-negative bacilli was predominant in CRS patients.

[Effects of Selaginella doederleinii on human nasopharyngeal carcinoma TW03 cells in vitro and its mechanism].

OBJECTIVE: To study the inhibition and mechanism of Selaginella doederleinii (SLG) on the growth of nasopharyngeal carcinoma (NPC) TW03 cells in vitro. METHODS: Cell suppression rates were measured by MTT assay, cell cycles were measured by flow cytometry (FCM) and expressions of Bc1-2 and Bax protein were detected by immunohistochemistry. RESULTS: Inhibition on the growth of NPC cell was intensed by SLG in a dose and time dependent manner in vitro (P < 0.05). The ratio of S phase cells increased and the ratios of G0/G1 and G2/M phase cells decreased, with the addition of SLG. Meanwhile, the expression of Bcl-2 protein was down-regulated and Bax protein was up-regulated. CONCLUSION: SLG could inhibit the growth of human NPC TW03 cells by directing cell cycle arrested at S phase, down-regulating Bcl-2 protein expression and up-regulating Bax protein expression.

[Dendritic cells transfected with recombinant adenovirus Ad5F35-LMP2 induces LMP2 specific immunity mediated by cytotoxic T lymphocytes in vitro].

OBJECTIVE: To observe whether dendritic cells (DCs) transfected with recombinant adenovirus Ad5F35-LMP2 induces LMP2 specific immunity mediated by cytotoxic T lymphocytes in vitro. METHODS: Dendritic cells have been generated in vitro, and cocultured with autologous T cell after the DCs were infected with Ad5F35-LMP2, then the proliferation of the induced T cells and their cytotoxic activity against CNE-2 tumor cells which express EBV-LMP2 protein on membrane were assessed by MTT method. RESULTS: The dendritic cells could be transfected with Ad5F35-LMP2 and the CTL activated by Ad5F35-LMP2-DC could effectively suppress the proliferation of CNE-2 cells compared with control groups. CONCLUSION: The dendritic cells transfected with recombinant adenovirus Ad5F35-LMP2 showed cytotoxicity effect by activating T lymphocytes.

[Relationship between the expression of TrkB and anoikis resistance in nasopharyngeal carcinoma line].

OBJECTIVE: To study the regulation of anoikis by tyrosine kinase receptor B (TrkB) in human nasopharyngeal carcinoma lines. METHODS; Expression levels of TrkB and brain-derived neurotrophic factor (BDNF) were evaluated by RT-PCR and Western blot. Colony formation ability of C666-1 was observed in soft agar. Proliferation rate and apoptosis, that change in cells by treating the TrkB inhibitor K252a and specificity ligand BDNF respectively under suspension culture, were measured by cell counting kit-8 (CCK-8) assay and the flow cytometry assay. The expression change of TrkB, BDNF and phosphorylation of serine threonine kinase (p-Akt) were investigated by Western blot analysis. RESULTS: TrkB and BDNF were identified in C666-1 cells. C666-1 cells could be decreased the proliferation of colony in soft agar by effect of K252a, but BDNF could make the colony prolific. K252a can inhibit the expression of TrkB in C666-1, and prevent p-Akt activation. And exogenous BDNF stimulated up-regulation TrkB and p-Akt, induced anoikis resistance. CONCLUSION: TrkB inhibits anoikis in nasopharyngeal carcinoma cells. Inhibiton of TrkB by K252a can induce anoikis, and may prove particularly effective in treatment of nasopharyngeal carcinoma.

[Effect of sodium salicylate on the auditory brain stem response threshold and expression of glutamic acid decarboxylase in spiral ganglion of juvenile and adult guinea pigs].

OBJECTIVE: To study the differences of regulation of sodium salicylate on the auditory brain stem response (ABR) threshold and expression of glutamic acid decarboxylase (GAD) protein in spiral ganglion of juvenile and adult guinea pigs. METHODS: Fourty juvenile guinea pigs which were born just four days and fourty adult guinea pigs which were born thirty days were selected. They were divided four groups (group A; group B; group C; group D). ABR threshold was detected before administration, after administration for 15 days and after administration stopped for 30 days. The protein expression of GAD were measured after administration for 15 days and after administration stopped for 30 days by the method of immunohistochemistry. RESULTS: ABR threshold of juvenile sodium salicylate groups (group C) was increased remarkably than that of before administration and the control after administration for 15 days (P < 0.001). ABR threshold of group C was returned to the level of that of before administration and after administration stopped for 30 days. ABR threshold of adult sodium salicylate groups (group D) was increased remarkably than that of before administration and the control after administration for 15 days (P < 0.001). ABR threshold of group D was kept the high level after administration stopped for 30 days. The protein expression of GAD of sodium salicylate groups (group C and D) was decreased than that of the control after administration for 15 days. The protein expression of group C was more visible regression than that of group D (t = 4.7, P < 0.001). The protein expression of group C was returned the level of before administration after administration stopped for 30 days, but the protein expression of group D was kept the high level. CONCLUSIONS: The results suggest that sodium salicylate can regulate differently ABR threshold and expression of GAD protein in spiral ganglion of juvenile and adult guinea pigs. The effects of sodium salicylate on ABR threshold and expression of GAD protein in spiral ganglion of juvenile pigs are more noticeable than that of adult guinea pigs, but these changes are easier to return the normal than that of adult guinea pigs.