The effects of the auditory brainstem response before and after fluoro-gold injection in medial geniculate body

OBJECTIVE

This study aimed to use the tree shrew as an otological model, not only to verify the location of the auditory pathway in tree shrews by fluoro-gold (FG) but also to elucidate the effects of the auditory brainstem response (ABR) before and after FG injection.

METHODS

FG was injected into the medial geniculate body (MGB) of experimental group (n=10).The normal group (n=10) was inserted the microsyringe, which was not perfused FG. Hearing was assessed by testing ABRs before and after the operation.

RESULTS

FG-labelled neurons were primarily distributed in the ipsilateral MGB, the ipsilateral and contralateral nuclei of the inferior colliculus (NIC), the superior olivary nucleus (SON), the dorsal cochlear nucleus (DCN), and the ventral cochlear nucleus (VCN). The ABR after FG injection caused a significant decrease in the wave amplitudes at 24 h that recovered by 72 h. However, the wave I-VI interpeak latencies in the right ear were shortened at 0 and 24 h post-surgery, whereas after 48 h, the interpeak latencies were prolonged.

CONCLUSIONS

The FG retrograde tracing technique accurately displays the anatomical location of the auditory pathway in the tree shrew. The change in ABR waves suggested that there was a functional abnormality in the central auditory pathway after FG injection. The auditory thalamus may have self-regulating properties.

[Inhibitive effect of matrine modification X on the growth of human nasopharyngeal carcinoma CNE2 cell xenografts in nude mice]

OBJECTIVE

To evaluate the inhibitive effect of matrine modification X on the growth of human nasopharyngeal carcinoma CNE2 cell xenografts in nude mice.

METHOD

Tumor model was established by subcutaneous inoculation of nasopharyngeal carcinoma cell CNE2 into nude mice, which was used to evaluate the antitumor effect of matrine modification X in vivo. The expression levels of Bax, Bcl-2, Caspase3 were detected by real-time PCR and western blot.

RESULT

The growth of xenografts in nude mice was significantly suppressed after application of matrine modification X in a dose-dependent manner. The inhibition rates were 32.55% and 44.89% when treated at medium and high dose respectively. Real-time fluorescence quantitative-PCR and Western Blot results showed that the expression of Bax and Caspase3 increased, while the expression of Bcl-2 decreased in a dose-dependent manner. The change of high dose group was obvious, and the difference was statistically significant (P < 0.05).

CONCLUSION

Matrine modification X could significantly inhibit the growth of human nasopharyngeal carcinoma CNE2 cell xenografts in nude mice, probably by inducing the apoptosis of nasopharyngeal carcinoma cells, and the possible mechanism is related to regulating the expression level of Bax/Bcl-2 and Casepase3.

Predictors of low bone mineral density of the stroke-affected hip among ambulatory individuals with chronic stroke

Risk of hip fracture is greater poststroke than in an age-matched healthy population, in part because of declining hip BMD. We found that individuals may be at risk of loss of hip BMD from muscle atrophy, asymmetrical gait, and poor affected-side ankle dorsiflexor strength. These impairments may be targeted during rehabilitation.

INTRODUCTION

This study aimed to determine predictors of low hip BMD on the stroke-affected side in people living in the community.

METHODS

Forty-three participants (female; 27.9%), mean age 62.4 ± 13.5 and 17.9 ± 32.8 months, poststroke with motor impairments underwent dual energy X-ray absorptiometry scans. Gait characteristics, isometric strength, body composition, and fasting plasma lipids were measured.

RESULTS

At entry, 34.9% (15/43) of the participants had low total hip BMD on the stroke-affected side. Of those with low BMD, 93.3% (14/15) had a step length symmetry ratio >1, indicating greater reliance on the non-paretic leg for weight bearing. Logistic regression analysis revealed that lower affected-side ankle dorsiflexor strength (ß = 0.700, p = 0.02), lower total body fat-free mass index (ß = 0.437, p = 0.02), and greater step length symmetry ratio during walking (ß = 1.135 × 10(3), p = 0.03) were predictors of low hip BMD.

CONCLUSION

Low BMD of the stroke-affected side hip is prevalent in over a third of individuals with lower limb motor impairments. These individuals may be at particular risk of accelerated loss of BMD at the hip from asymmetrical gait pattern and poor affected-side ankle dorsiflexor strength. These impairments are intervention targets that may be addressed during rehabilitation which includes resistance training and addresses gait impairments.

[The nucleus origin of acoustically evoked short latency negative response in guinea pigs]

OBJECTIVE

This study established a model of acoustically evoked short latency negative response (ASNR) in guinea pigs. Stereotaxic coordinate guided electrolytic lesion was applied to animal brainstem nuclei, the vestibular nucleus and the cochlear nucleus, to define the neural origin of ASNR.

METHODS

Twenty four guinea pigs with normal hearing were randomly divided into the control group (8 subjects, 16 ears) and the deafened group (16 subjects, 32 ears). Each animal experienced the auditory brainstem response (ABR) test. According to the presence of ASNR, the deafened group was further divided into ASNR group and non-ASNR group. Electrolytic lesion was conducted to the vestibular nucleus and cochlear nucleus respectively, followed by ABR test. The lesion structures were verified by brainstem slice and microscope.

RESULTS

In deafened group, the ASNR was elicited in 10 ears (31.3%). The ASNR was eliminated due to the electrolytic destruction to the vestibular nucleus, but it remained unchanged after the same procedure to the cochlear nucleus.

CONCLUSION

It is clear that the ASNR is originated from the vestibular nucleus, but not the cochlear nucleus.

[Investigate of the learning curve of cochlear implantation]

OBJECTIVE

To investigate the learning curve of cochlear implantation and its guiding significance for clinical surgery.

METHODS

A retrospective analysis of the clinical data of two otologists in early cochlear implant surgeries, including 98 cases of Dr. A and 54 cases of Dr. B.Statistics of the two doctors incidence of complications and operating time. Operation time as index were drawing a, b two groups of cases of scatter plot, the oscillating sine curve model Y = sin(X)-P/2 and logarithmic curve model Y = b1ln(X)+b0 curve fit were analyzed. Then, extract the early 90 cases of surgery by Dr. A which was divided into a, b, c three groups with 30 cases a group. The operating time and complications were further compared and analyzed(SPSS 16.0).

RESULTS

From the operation sequence,A and B physicians, early operation cases cost more operating time, and more complications.Learning curve before and after about 30 cases appeared inflection point, showing a rapid decline in period (learning phase) and slow decline period (consolidation phase) in two stages.Group contrast to Dr. A's early 90 consecutive cases, the operating time of Phase b and Phase c decreased significantly than Phase a (P(a-b) < 0.01, P(a-c) < 0.01), while there was no significant difference between group Phase b and Phase c (P(b-c) = 0.68), the complication rate of Phase b and Phase c decreased significantly than Phase a (P(a-b) < 0.01, P(a-c) < 0.01), while there was no significant difference between group Phase b and Phase c (P(b-c) = 0.15).

CONCLUSIONS

Our department of cochlear implantation followed the learning curve rule. The minimum number of cases that should accumulate in the learning phase needs about 30 cases.

Matrine-induced apoptosis of human nasopharyngeal carcinoma cells via in vitro vascular endothelial growth factor-A/extracellular signal-regulated kinase1/2 pathway inactivation

Matrine, a main active extract from Sophora flavescens Ait, has been demonstrated to exert anticancer effects on various cancer cell lines, such as malignant melanoma, breast cancer, and lung cancer. However, it is currently unclear whether matrine could also elicit an inhibitory effect on growth of nasopharyngeal carcinoma (NPC), let alone the possible molecular mechanisms. Therefore, in a previous study, we investigated matrine-induced proliferation inhibition and apoptosis in NPC cells. It was shown that proliferation of human NPC cells (CNE1 and CNE2) was significantly diminished by matrine in a dose- and time-dependent manner, and apoptosis was induced in both 2 NPC cells, particularly in CNE2 cells. Moreover, the increased apoptosis rate in matrine-treated CNE2 cells confirmed the proapoptotic activity of matrine. We further found that matrine treatment dose- and time-dependently reduced the levels of vascular endothelial growth factor-A (VEGF-A), and inactivated extracellular signal-regulated kinase1/2 (ERK1/2), followed by increased expression of downstream target caspase-3. Overall, we conclude that matrine could induce apoptosis of human NPC cells via VEGF-A/ERK1/2 pathway, which supports the potential use of matrine in clinically treating NPC.

[Digitalization study of sonotubometry device]

OBJECTIVES

Sonotubometry is wildly used in developed countries, offers a easy, versatile and objective way to assess the function of Eustachian tube. The objectives of this study are to develop a low-cost digitalized device.

METHODS

The digitalized sonotubometry device was made of a personal computer with sound input and output accessories. The PC sound card, connected to a signal amplifier, exported probe band noise, while feedback sound was collected by a microphone. All 36 volunteers (72 ears) were involved in the sonotubometry test with JK-04A and CHN-08, in the conditions of dry-swallowing and wet-swallowing. The data were statistically analyzed using SPSS 13.0.

RESULTS

The basic electroacoustic performance of the CHN-08 was acceptable. CHN-08 (7 kHz) detection and JK-04A consistency of kappa index was 0.472; CHN-08 (8 kHz) and JK-04A consistency of kappa index was 0.487; CHN-08 (7 kHz) and CHN-08 (8 kHz) consistency of kappa index was 0.688.Under the JK-04A, CHN-08 (7 kHz) and CHN-08 (8 kHz) three setups, Eustachian tube opening frequency was significantly lower for wet-swallowing than dry-swallowing, P < 0.05.

CONCLUSIONS

A low-cost digitalized sonotubometry is successfully developed. Its electroacoustic performance proved acceptable by authority assessments. The detection rate of CHN-08 is in accordance with that of JK-04A moderately. The study revealed that Eustachian tube is opened more easily by dry-swallowing than by wet-swallowing.

14-Thienyl methylene matrine (YYJ18), the derivative from matrine, induces apoptosis of human nasopharyngeal carcinoma cells by targeting MAPK and PI3K/Akt pathways in vitro

BACKGROUND/AIMS

Nasopharyngeal carcinoma (NPC) is a distinctive type of head and neck cancer with the highest incidence in South China. Previous studies have proved that matrine, a main alkaloid isolated from Sophora flavescens Ait, has antitumor activity against NPC. However, the effect is not so pronounced and the underlying mechanism remains largely unclear. Here we investigated whether 14-thienyl methylene matrine (YYJ18) that was derived from matrine could exert more effective suppression activity on NPC, along with the underlying mechanism.

METHODS

NPC cell lines CNE1, CNE2 and HONE1 were treated with YYJ18. Cell proliferation and apoptosis were determined by MTT assay and flow cytometry. Activation of mitogen-activated protein kinases (MAPK) and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathways were determined by Western blotting and quantitative RT-PCR.

RESULTS

YYJ18 remarkably inhibited proliferation and induced apoptosis of all three NPC cell lines in a dose-dependent manner, especially in CNE2 cells. Furthermore, YYJ18 treatment significantly suppressed phosphorylation of p38 in CNE2 cells, but upregulated phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2) and Akt. Next, alterations in downstream signaling were found, including activation of BCL2-associated X protein (Bax), caspase-3 and inactivation of B-cell CLL/lymphoma 2 (Bcl-2).

CONCLUSION

We demonstrate the potent inhibitory effects of 14-thienyl methylene matrine on NPC cells for the first time, which could be mediated by modulation of MAPK and PI3K/Akt pathways.

[The inhibited effect of matrine on human nasopharyngeal carcinoma CNE2 cells and the expression of apoptosis related gene Caspase in vitro]

OBJECTIVE

To evaluate the inhibited effect of matrine on human nasopharyngeal carcinoma CNE2 cells and the expression of apoptosis-related gene Caspase-3 mRNA, Caspase-3, Caspase-8, Caspase-9 protein. And to explore the inhibiting effect of matrine on the apoptosis of human nasopharyngeal carcinoma CNE2 cells.

METHOD

In vitro experiments, MTT assay was used to detect the effect of matrine on CNE2 cell proliferation with different concentration. The expression levels of Caspase-3 were detected by real-time PCR. Western Blot was used to gauge the levels of Caspase-3, Caspase-8 and Caspase-9 protein.

RESULT

MTT results showed significant inhibitory action of matrine on CNE2 cells proliferation in does-dependent manner, which could up-regulate the expression of Caspase-3 mRNA and Caspase-3, Caspase-8, Caspase-9 protein in a dose-dependent manner.

CONCLUSION

Matrine could inhibit CNE2 cells proliferation in a does-dependent,that was closely related to the up-regulation of Caspase-3 mRNA and Caspase-3, Caspase-8 and Caspase-9 protein expression, and to the cascade reaction of Caspase.

Molecular alterations of the WWOX gene in nasopharyngeal carcinoma

The WW domain-containing oxidoreductase (WWOX) gene is a candidate tumor suppressor gene. However, its exact mechanism is unclear. This study aimed to investigate the role of the WWOX gene in the development of nasopharyngeal carcinoma (NPC). Tissues were collected from 65 NPC patients. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis and immunohistochemistry were performed on NPC tissues to determine the expression of WWOX in NPC. The status of WWOX promoter methylation was analyzed by methylation-specific PCR. Moreover, a PCR-based loss of heterozygosity (LOH) assay was conducted to detect the presence of WWOX deletion in NPC. The expression of WWOX in NPC tissues was significantly downregulated compared with that in non-tumorous tissues (P<0.05). The low expression of WWOX was significantly correlated with clinical TNM stage (P<0.05). In addition, methylation of WWOX was detected in 27 (87%) of 31 WWOX protein negative tissues, suggesting that methylation of the WWOX promoter may regulate its expression. We found that a relatively high percentage of LOH was observed in NPC tissues. A significant inverse correlation between WWOX expression and methylation of its promoter was found in NPC tissue (rs=-0.582, P=0.001). However, LOH was not correlated with WWOX expression and methylation of its promoter. Our results show that WWOX gene alteration is an early genetic alteration and may contribute to tumorigenesis of NPC. WWOX may be an important prognostic marker in NPC.

The effect of nitidine chloride on the proliferation and apoptosis of nasopharyngeal carcinoma cells

PURPOSE

This study was conducted to investigate the effect of nitidine chloride (NC) on the proliferation and apoptosis of nasopharyngeal carcinoma cell line CNE1, CNE2, TWO3, and C666-1, and to explore its antitumor mechanism.

METHODS

NC was dissolved in IMDM medium and cultured with nasopharyngeal carcinoma cell line CNE1, CNE2, TWO3 and C666-1. Cell morphology, cell proliferation, cell apoptosis, p53 mRNA and p53 protein levels were assessed.

RESULTS

After incubation with NC for 24 h, typical apoptotic morphology was observed. NC inhibited the proliferation and induced apoptosis of all 4 cell lines in a time-dose dependent manner. p53 mRNA and p53 protein levels were significantly increased.

CONCLUSIONS

NC inhibited proliferation and induced apoptosis of nasopharyngeal carcinoma cells with upregulation of p53 gene.