前庭导水管扩大致突发性耳聋的临床治疗体会

目的探讨前庭导水管扩大致突发性耳聋的治疗方案及疗效。方法分析2011年1月～2 0 1 1年1 2月住院治疗的7例因前庭导水管扩大致突发性耳聋患儿的临床资料。根据入院前听力损失程度的不同分为两组,分别采用不同的治疗方案。对轻、中度突聋患儿采用银杏叶提取物加泼尼松治疗;对重度、极重度突聋患儿采用单唾液酸四己糖神经苷脂加泼尼松治疗,观察其疗效。结果在听力损伤为轻、中度时,两种治疗方案没有显著差别;但听力损伤为重度、极重度时,用单唾液酸四己糖神经节苷脂加糖皮质激素治疗,听力改善效果比较明显。结论采用单唾液酸四己糖神经节苷脂加糖皮质激素治疗因前庭导水管扩大导致突发性耳聋特别是重度、极重度聋效果明显。     

One-step synthesis of green emission carbon dots for selective and sensitive detection of nitrite ions and cellular imaging application

In recent years, carbon dot (CD)-based fluorescent sensors for selective ions or small biomolecules have drawn great attention. In this work, highly fluorescent CDs (QY = 21%) were prepared from 2,3-diamino pyridine as the precursor through a facile solvothermal process. The CDs showed high stability and a green emission in aqueous, and the optimal emission wavelength of CDs is 508 nm under the excitation wavelength of 438 nm. Interestingly, a CDs-based nanoprobe was developed for a selective and sensitive fluorescence quenching response to NO₂⁻ in water, and the quenching mechanism was investigated in the work. Besides, the recovery rates of NO₂⁻ in the range of 98–103.5% were found to be acceptable, indicating that the proposed CDs could be act as potential candidates for determination of nitrite ions in real samples. Meanwhile, the nanoprobe was also successfully employed in a visualization biosensing platform for determination of NO₂⁻ in living cells due to its eminent biocompatibility.

Schematic route of the carbon dots and their applications for the nitrite detection.     

Prognostic value of parapharyngeal extension in nasopharyngeal carcinoma treated with intensity modulated radiotherapy

Background and purpose

The development of improved diagnostic and therapeutic techniques has revolutionized the management of nasopharyngeal carcinoma (NPC). The purpose of this study is to revaluate the prognostic value of parapharyngeal extension in NPC in the IMRT era.

Material and methods

We retrospectively reviewed data from 749 biopsy-proven non-metastatic NPC patients. All patients were examined with magnetic resonance imaging (MRI) and received intensity-modulated radiotherapy (IMRT) as the primary treatment.

Results

The incidence of parapharyngeal extension was 72.1%. A significant difference was observed in the disease-free survival (DFS; 70.3% vs. 89.1%, P < 0.001), distant metastasis-free survival (DMFS; 79.3% vs. 92.0%, P < 0.001), and local relapse-free survival (LRFS; 92.8% vs. 99.0%, P = 0.002) of patients with and without parapharyngeal extension. Parapharyngeal extension was an independent prognostic factor for DFS and DMFS in multivariate analysis (P = 0.001 and P = 0.015, respectively), but not LRFS. The difference between DMFS in patients with or without parapharyngeal space extension was statistically significant in patients with cervical lymph node metastasis (P < 0.001).

Conclusions

In the IMRT era, parapharyngeal extension remains a poor prognosticator for DMFS in NPC, especially in patients with positive lymph node metastasis. Additional therapeutic improvements are required to achieve a favorable distant control in NPC with parapharyngeal extension.     

Clinical treatment considerations in the intensity-modulated radiotherapy era for patients with N0-category nasopharyngeal carcinoma and enlarged neck lymph nodes

Background: Nasopharyngeal carcinoma (NPC) shows a high proportion of lymph node metastasis, and treatment guidelines have been developed for positive nodes. However, no irradiation guidelines have been proposed for patients with enlarged neck lymph nodes (ENLNs) that do not meet the radiological criteria of 10 mm in diameter for positive lymph nodes. This study aimed to determine the prognostic value and radiation dose for ENLNs in N0-cate-gory NPC patients treated with intensity-modulated radiotherapy (IMRT). Methods: We reviewed the medical data of 251 patients with non-metastatic, N0-category NPC treated with IMRT. Receiver operating characteristic curves were used to calculate the cut-off value of the ENLN diameter for the prediction of disease failure.The biological equivalent dose (BED) for ENLNs was calculated. Patient survival was compared between the smal and large ENLN groups. Independent prognostic factors were identified using the Cox proportional hazards model. Results: The estimated 4-year regional relapse-free survival rate was higher in patients with ENLNs ≥5.5 mm thanin those with ENLNs <5.5 mm (100% vs. 98.8%, P= 0.049), whereas disease-free, overall, and distant metastasis-free survival rates were similar between the two groups. After adjusting for various factors, ENLN diameter was not identi-fied as an independent prognostic factor (P > 0.05 for all survival rates). In the subgroup analysis, patients receiving BED ≥72 Gy had a similar prognosis as patients receiving BED <72 Gy in both the small and large ENLN groups. Themultivariate analysis also confirmed that BED≥72 Gy was not associated with significantly improved prognosis in patients with N0-category NPC. Conclusions: A BED of 72 Gy to ENLNs is considerably sufficient to provide a clinical benefit to patients with N0-cate-gory NPC. Prospective studies are warranted to validate the findings in the present study.     

Protective effects of tetramethylpyrazine on kainate-induced excitotoxicity in hippocampal culture

Tetramethylpyrazine (TMP) is the major component extracted from the Chinese herb, Chuanxiong. This study focuses on the protective effect of tetramethylpyrazine in kainate-induced excitotoxicity in rat hippocampus. Primary neuronal cultures raised from cells isolated from the hippocampi of 7-day old rats were treated with kainate (75-450 microM) for 12, 24, and 48 h. Our results revealed that kainate induced neuronal damage in a dose- and time-dependent manner, reaching maximal damage at 150 microM and 24 h and persisted for higher doses and 48 h. In addition, 1 h of kainate (150 microM) treatment led to significant generation of free radicals and reduction of mitochondrial membrane potential (MMP) which persisted for > or = 4 h on continued exposure. Ten minutes pretreatment with 1 or 5 microM tetramethylpyrazine dose dependently and significantly attenuated the kainate-induced damage. Taken together, the results suggest that multiple mechanisms including protection of mitochondria, decrease in free radical generation and scavenging of free radicals might be involved in TMP's protection against kainate induced cell toxicity.     

Mechanisms in mediating the anti-inflammatory effects of baicalin and baicalein in human leukocytes

To evaluate the possible mechanisms responsible for the anti-inflammatory effects of baicalin or baicalein, phorbol-12-myristate-13-acetate (PMA)- or N-formyl-methionyl-leucyl-phenylalanine (fMLP)-activated inflammatory responses of peripheral human leukocytes were studied. Both baicalin and baicalein diminished fMLP- or PMA-induced reactive oxygen intermediates production in neutrophils or monocytes. Neither baicalin nor baicalein prevented the protein kinase C (PKC)-dependent assembly of the NADPH oxidase. Conversely, myeloperoxidase (MPO) activity was inhibited by baicalin or baicalein. fMLP-induced activation of leukocytes, as reflected by increased surface expression of Mac-1 (CD11b/CD18) and Mac-1-dependent neutrophil adhesion, were also inhibited by baicalin or baicalein. Furthermore, baicalein, but not baicalin, impeded fMLP- or AlF(4)(-)-induced Ca(2+) influx. We conclude that impairment of reactive oxygen intermediates production, through scavenging reactive oxygen intermediates by baicalin, or antagonizing ligand-initiated Ca(2+) influx by baicalein, accounts for the inhibition of Mac-1-dependent leukocyte adhesion that confers the anti-inflammatory activity of baicalin or baicalein.