Aplasia ras homolog member I is downregulated in gastric cancer and silencing its expression promotes cell growth in vitro.

BACKGROUND AND AIM: Aplasia ras homolog member I (ARHI) is a maternally imprinted tumor suppressor gene. ARHI protein is widely expressed in many types of human tissues; however, its expression is frequently reduced or absent in various tumors and plays a tumor suppressor role for in vitro study. In this study, we investigated the expression level of ARHI in gastric cancer in order to investigate the function of ARHI and signaling pathways that might be linked during gastric cancer development. METHODS: ARHI mRNA and protein expression levels were analyzed in primary gastric cancer tissues, adjacent noncancerous gastric tissues and gastric cancer cell lines using semi-quantitative polymerase chain reaction, western blotting and immunohistochemistry, respectively. RESULTS: Our results showed that both mRNA and protein expression levels of the ARHI gene were significantly downregulated (P < 0.05) in gastric cancer tissues and cell lines compared to the corresponding normal control groups. The protein expression level of ARHI was not associated with age, gender, location of tumor, tumor size or metastasis in patients with gastric cancer. However, a significant correlation between the level of ARHI protein expression and the degree of tumor differentiation and Tumor-Node-Metastasis stage was observed (P < 0.05). Furthermore, results of the methyl thiazolyl tetrazolium and Transwell assays and flow cytometric analysis showed increased cell proliferation, migration and anti-apoptotic capacities in the well-differentiated gastric cancer MKN-28 cell line, which has stably silenced ARHI protein expression. CONCLUSION: Our data indicate that ARHI expression is downregulated in human gastric cancer and it may be a novel tumor suppressive target for gastric cancer therapy.

[Changes of BDNF expression in neurons in traumatic brain injury rats].

OBJECTIVE: To investigate changes of brain derived neurotrophic factor (BDNF) expression in neurons in traumatic brain injury (TBI) rats. METHODS: Adult SD rats were divided into sham and operated group resulted from hammer fall contusion (30 cm high, 50 g weight). Thirteen rats in each group were used. Some of animals (n = 6 in each group) were used to perform immunohistochemistry and in situ hybridization, and the other (n = 7) was used for RT-PCR. After NSS assessment was determined at 1, 3, 8, 13 days, TBI rats were sacrificed, brain tissues were then harvested to measure BDNF level. Data were analyzed by using statistic method. RESULTS: A increased NSS scores (P < 0.05) was observed after TBI, which implied the significant neurobehavioral changes in rats. But a gradual decreasing NSS scores (P < 0.05) was also observed along with time prolonged. Severe neurological severity function was seen following TBI, and it presents a gradual improvement indicated by decreasing NSS scores, despite BDNF mRNA level in whole brain tissue did not present a significant change, the BDNF expression (indicated by optical density values analysis) in subcellular structure, known as neurons, exhibited a significant increase, when compared with that of sham group (P < 0.05). This could simultaneously accompany with the decrease in the number of neurons in TBI rats. CONCLUSION: TBI rats exhibit a neuroplasticity with the BDNF upregulation in neurons following injury.

Relationship between myocardial ultrasonic integrated backscatter and mitochondria of the myocardium in dogs.

OBJECTIVE: This study aimed to explore the relationship between integrated backscatter (IBS) and mitochondria in arrested myocardium. METHODS: Twelve open-chest dogs were randomly divided into two groups: one group with cardiac arrest in systole and the other with cardiac arrest in diastole. IBS images at parasternal papillary muscle short-axis view were stored at different time frames (0, 30, and 60 min after cardiac arrest). The values of ultrasonic IBS were obtained using the acoustic densitometry technique. After ultrasound examination, tissue samples of corresponding times were harvested and observed under the transmission electron microscope. The microscopic images were analyzed using a computer imaging analysis system to obtain the stereological parameters of mitochondria. The correlation between IBS and the stereological parameters was analyzed. RESULTS: After cardiac arrest, swollen mitochondria with electron-lucent matrix could be observed in some myofibers following the progression of time. The alteration of IBS correlated well with that of mitochondrial stereological parameters, such as volume density (Vv), surface density (Sv), average volume (v), average surface area (s), and specific surface (Rsv, ratio between surface and volume). CONCLUSION: Mitochondria might be an important scatterer in the myocardium for IBS.