Hearing Improvement in A/J Mice via the Mouse Nerve Growth Factor

OBJECTIVES: To investigate the otoprotective effects of mouse nerve growth factor (mNGF) in A/J mice. METHODS: The mice at postnatal day 7 (P7) were randomly separated into a mNGF treated group (mNGF group) and a distilled water (for injection) treated group (control group). The mNGF dissolved in distilled water or distilled water alone was given to the mice once every other day from P7 by intramuscular injection in the hips. The otoprotective effects of mNGF in A/J mice were observed in a time course manner. The thresholds of auditory-evoked brainstem response (ABR) were tested from the age of the 3rd to the 8th week. Sections of the inner ears were stained by hematoxylin and eosin, and spiral ganglion neurons (SGNs) were observed at the age of the 3rd, the 6th,and the 8th week. Counts of whole mount outer hair cells (OHCs) in the cochleae were made at the age of 8 weeks. Expression of apoptosis related genes was determined by quantitative real-time polymerase chain reaction and Western blotting. RESULTS: ABR thresholds of the mNGF group were significantly lower than those of the control group at the age of the 6th and the 8th week. Moreover, the mNGF preserved OHC and SGN in the mouse cochleae in this period. Further experiments showed that the expression of caspase genes (including caspase-3) was inhibited in the mouse inner ears in the mNGF group. CONCLUSION: The mNGF improves hearing in A/J mice by preserving SGN and OHC in the cochleae.

Antigen-antibody reaction model of solid-phase surface and active biochip system / 生物医学工程学杂志

To overcome the present limitations of passive biochip, based on the basic principle of antigen-antibody reaction, we develop an antigen-antibody reaction model of solid-phase surface and design a novel active biochip system according to this model, which introduces the negative pressure and controlling devices to control the immunoreactions on the nitrocellulose (NC) membrane. From the computer simulation results, this is a rapid, stable, robust and practicable system, which can be used to increase the efficiency of immunoreactions and improve the reproducibility and accuracy of biochip analysis.

Overexpressed Gene YA61 Cloned from Human Gastric CarcinomaCell SGC-7901 and Its Sequencing / 生物化学与生物物理进展

To clone overexpressed gene from human gastric carcinoma cell SGC-7901, DDRT-PCR technique is used with human gastric epithelial cell GES-1 as control. After cloned into pGEM -T vector, YA61, one of the overexpressed genes, was analyzed by dot blot and was sequenced then. The sequence gotten was then compared to GenBank data and analyzed by NCBI ORF Finder. Dot blot results showed that the gene YA61 was overexpressed in human gastric carcinoma cell SGC-7901. NCBI's sequence similarity search indicated that the gene YA61 was a new gene sequence. Open reading frame analysis demonstrated that the gene YA61 had one complete open reading frame. In conclusion, the gene YA61 was a new gene sequence that was overexpressed in human gastric carcinoma cell SGC-7901.

Identification of down-regulated genes in cardiac fibroblasts stimulated by angiotensin Ⅱ / 中国病理生理杂志

AIM: To identify the down-regulated genes in adult rat cardiac fibroblasts (CF) stimulated with angiotensin Ⅱ (AngⅡ). METHODS: Suppression subtractive hybridization (SSH) was performed between the CF stimulated by AngⅡ (driver) and unstimulated CF (tester) to generate subtractive cDNA library. The library was screened with dot blots hybridization to further verify the differentially expressed cDNA clones. Partial positive clones were sequenced and BLAST analyzed. RESULTS: Seventeen down-regulated genes related to intracellular signal transduction, transcriptional repression, deposition of fibrous matrix and cellular cytoskeletal rearrangement, and 4 new expression sequence tags (EST) were acquired. CONCLUSION: SSH is a powerful technique with high sensitivity for the detection and clone of down-regulated genes expressed in CF induced by AngⅡ, which is helpful to clarify the mechanism of cardiac remodeling.

CHANGES OF ACTIVITIES OF MITOCHONDRIAL MEMBRANE BINDING ENZYMES IN RATS FED WITH LOW—Se DIET / 西安交通大学学报(医学版)

In this article the activities of succinic dehydrogenase, H~+ -ATPase and creatine kinase in skeletal muscle and heart mitochondria of rats fed with low-Se diet from kashin-beck disease area for 3 to 5 months were observed. The experiments showed that the activities of these three membrane binding enzymes were decreased significantly in mitochondria of rats fed with low-Se diet for 3 to 5 months, as compared to rats suplemented with sodium selenite, but still had not reached the levels in rats fed with diet from Xi'an area.These results suggested that the disturbance of energy metabolism may be induced when the rats fed with low-Se diet for long term.