AIM:To explore the effect of long-term (6 months) endogenous testosterone deprivation by orchidectomy on the function of voltage-dependent potassium channels of vascular smooth muscle cells in rats. METHODS:Wistar rats were raised for 6 months after castration. Isometric tension measurement of aortic rings,whole-cell patch-clamp technique and Western blotting analysis were employed to examine the functional and posttranscriptional alterations of voltage-dependent potassium channels. RESULTS:Voltage-dependent potassium channel blocker,4-aminopyridine,significantly decreased the constriction of aortic artery rings from male rats after 6-month castration. In castrated rats the amplitude of voltage-dependent potassium currents of aortic artery smooth muscle cells was significantly decreased compared with that in control rats. Meanwhile,the expression of Kv 1.5 channel protein,which plays an essential role in mediating vasomotor function,was also reduced. The functional and molecular alterations of voltage-dependent potassium channels were both restored when the rats were concomitant applied with physiological level of testosterone after castration. CONCLUSION:Long-term deprivation of endogenous testosterone in rats significantly attenuates the function of voltage-dependent potassium channels,and the decreases in expression of Kv1.5 channel protein accounts for this alteration. Long-term application of physiological concentration of testosterone,which recovered the impaired function of voltage-dependent channels,may be beneficial for male gender with hypotestosteronaemia.

OBJECTIVE: To study the radiation-sensitizing function and preliminary mechanism of paclitaxel in radiation-resistant nasopharyngeal carcinoma cells. METHOD: X-ray dose fractionated irradiation technology to build radiation-resistant subline of nasopharyngeal carcinoma; CNE-2S1 was treated with paclitaxel alone or combined with radiation therapy, while control group treated with radiation therapy; cell colony formation assay was used to observe sensitizing effect of paclitaxel on radiotherapy; flow cytometry analysis was used to analyze cell cycle distribution and apoptosis ratio of different treatment groups; immunoblotting was used to analyze SHP-1 expression levels of different treatment groups. RESULT: Nasopharyngeal carcinoma cells resistant to radiation was successfully established; cell colony formation assay showed that paclitaxel has obvious sensitizing effect on radiotherapy; FACS results showed that: CNE-2S1 treated by paclitaxel were arrested in G2M phase; paclitaxel and radiotherapy treatments significantly improved the CNE-2S1 apoptosis ratio; Western blot results showed that paclitaxel and combined radiotherapy can reduce the CNE-2S1 cells SHP-1 expression levels. CONCLUSION Paclitaxel enhanced radiation therapy for nasopharyngeal carcinoma cells resistant to radiation, and SHP-1 may be involved in this progress.
Apoptosis ; drug effects ; Carcinoma ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Humans ; Nasopharyngeal Carcinoma ; Nasopharyngeal Neoplasms ; pathology ; Paclitaxel ; pharmacology ; Protein Tyrosine Phosphatase, Non-Receptor Type 6 ; metabolism ; Radiation Tolerance ; drug effects

BACKGROUND: Resveratrol is a naturally occurring phytoalexin present in grapes, peanut and some herbs. It has been demonstrated to produce a variety of biological actions, such as anticancer, antiinflammation. Accumulating line of evidence supported the view that resveratrol may exert protective effect on cardiovascular system. However, its protective mechanism is not completely understood.OBJECTIVE: To investigate the anti-ischemic effect and mechanism of resveratrol (Res) on acute myocardial infarction in rats.DESIGN: Randomly grouping paralleled control study.SETTING: Pharmacological Laboratory of Harbin Medical University, Biopharmaceutical Key Laboratory of Heilongjiang Province-Incubator of State Key Laboratory.MATERIALS: The experiment was carried out in Department of Pharmacology of Harbin Medical University from March 2005 to July 2005.Totally 80 male Wistar rats weighting 250-300 g were selected in this study. Among them, 60 rats after operation successful modeling were randomly grouped into 5 groups: sham operation group, blank control group,resveratrol 5 mg/kg, 15 mg/kg and 45 mg/kg groups with 12 in each group.METHODS: Acute myocardial infarction (AMI) model was induced by ligation of the anterior branch of the left coronary artery in rat, Sham operation group: The same suture was put through but not ligated. Resveratrol group: Rats were injected with 5, 15 and 45 resveratrol mg/kg provided by Hunan Huaguang Biological Products Company Limited (batch number: 20050221, purity ≥99%) and ligated after 10 minutes. Model group: The same volume saline was injected for 10 minutes and then rats were ligated. Observe and record ST segment of standard limb lead Ⅱ electrocardiogram (ECG)after 1, 5, 10, 15, 30 minutes after ligating the left anterior decendingcoronary artery. After 6-hour ischemia, the infarct size areas was identified with the myocardium by 2, 3, 5-triphenyltetrazolium chloride (TTC) stain; the activities of serum .creatine kinase (CK)and lactate dehydrogenase (LDH) were determined by spectrophotometric method; the apoptosis in cardiomyocyte was detected by d-UTP end labeling method mediated with tagged deoxynucleotide transferase in situ (TUNEL); apoptosis-related proteins of Bcl-2, Bax and Fas expression were measured with estreptomicina avidin peroxidase chain. Measurement data were compared with t test.MAIN OUTCOME MEATURES: ST increase; the activities of serum creatine kinase (CK) and lactate dehydrogenase (LDH); the infarct size areas and the apoptosis rate in cardiomyocyte; the. expression of apoptosis-related proteins of Bcl-2, Bax and Fas.RESULTS: All of the 60 rats entered the final analysis. ① ST segment raise in high dosage group was lower than that in model group 1, 5 and 10 minutes after ligation (P ＜ 0.05), and it was also lower than that in model 15 and 30 minutes after ligation (P ＜ 0.05). This effect was dose-dependent. ② Infarct size in each dosage group was smaller than that in model group (P ＜ 0.05). This effect was dose-dependent. ③ The activities of CK and LDH in different dosages of resveratrol groups were significantly lower than those in model group (P ＜ 0.05). This effect was dose-dependent. ④ Apoptosis index in model group was higher than different dosages of resveratrol groups (P ＜ 0.05); The expression levels of Bax and Fas proteins in model group were higher than those in high and middle dosages of resveratrol groups (P ＜ 0.05); The expression level of Bcl-2 protein was lower than that in high and middle dosges of resveratrol groups (P ＜ 0.05).These effects were dose-dependent.CONCLUSION: Resveratrol can protect acute myocardial ischemic injury induced by coronary artery of ligated rats, and the effect is dose-dependent.Effect of resveratrol on myocardial ischemia is related to adjusting expressions of Fas, Bcl-2 and Bax and inhibiting myocardial apoptosis.

The real-time monitoring of cerebral hemorrhage can reduce its disability and fatality rates greatly. On the basis of magnetic induction phase shift, we in this study used filter and amplifier hardware module, NI-PXI data-acquisition system and LabVIEW software to set up an experiment system. We used Band-pass sample method and correlation phase demodulation algorithm in the system. In order to test and evaluate the performance of the system, we carried out saline simulation experiments of brain hemorrhage. We also carried out rabbit cerebral hemorrhage experiments. The results of both saline simulation and animal experiments suggested that our monitoring system had a high phase detection precision, and it needed only about 0.030 4s to finish a single phase shift measurement, and the change of phase shift was directly proportional to the volume of saline or blood. The experimental results were consistent with theory. As a result, this system has the ability of real-time monitoring the progression of cerebral hemorrhage precisely, with many distinguished features, such as low cost, high phase detection precision, high sensitivity of response so that it has showed a good application prospect.
Algorithms ; Animals ; Cerebral Hemorrhage ; diagnosis ; Computer Systems ; Magnetics ; Rabbits ; Software

This study was aimed to improve the sensitivity of magnetic induction phase shift detection system for cerebral hemorrhage. In the study, a cerebral hemorrhage model with 13 rabbits was established by injection of autologous blood and the cerebral hemorrhage was detected by utilizing magnetic induction phase shift spectroscopy (MIPSS) detection method under the feature band. Sixty five groups of phase shift spectroscopy data were obtained. According to the characteristics of cerebral hemorrhage phase shift spectroscopy under the feature hand, an effective method, B-F distribution, to diagnose the severity of cerebral hemorrhage was designed. The results showed that using MIPSS detection method under feature band, the phase shift obviously growed with increase of injection volume of autologous blood, and the phase shift induced by a 3-mL injection reached -7.750 3 degrees ± 1.420 4 degrees. B-F distribution could effectively diagnose the severity of cerebral hemorrhage. It can be concluded that the sensitivity of the cerebral hemorrhage magnetic induction detection system is improved by one order of magnitude with the MIPSS detection method under the feature band.
Animals ; Cerebral Hemorrhage ; diagnosis ; Magnetic Phenomena ; Magnetics ; Rabbits ; Spectrum Analysis ; methods

Objective:To develop a simple, practical and repeatable ultrasound method to locate the muscle at the trigger point of female myofascial pelvic pain(MPP), which can provide imaging reference for clinical precision treatment.Methods:A total of 113 patients with suspected MPP who came to the Women′s Hospital School of Medicine Zhejiang University from September 1, 2021 to April 20, 2023 were prospectively selected. The gynecologist performed internal examination with index finger on some pelvic floor muscles (puborectalis, pubococcygeus, iliococcygeus, coccygeus) and pelvic wall muscles (piriformis and obturator internus) respectively, searched for the muscles where the pain trigger point was located, and scored the pain by referring to visual analogue scale (VAS) and numerical rating scale (NRS), and then referred the patients to the ultrasound department. The ultrasound doctor used transvaginal ultrasound to display the above muscle groups in real time for observation and appropriate pressure. The muscle where the painful trigger point was located was found through tenderness and the pain score was performed. The two scores were compared for consistency and difference analysis.Results:The trigger point was clear and of good reproducibility. For the location and score of pain trigger points located in bilateral puborectalis, pubococcygeus and coccygeus, there was a strong consistency between the tenderness guided by vaginal ultrasound probe and clinical palpation (the consistency rate was ≥70%), and there was no significant difference in the pain scores of the trigger points located in the puborectalis muscle and coccygeal muscle between the two methods ( P>0.05), and there was statistically significant difference in the pain scores of the trigger points located in the other pelvic floor and pelvic wall muscles (all P<0.05). At the same time, ultrasonic examination made up for the deficiency of clinical palpation in the evaluation of piriformis muscle. Conclusions:The present method for finding the trigger point of MPP guided by the ultrasound probe is a new non-invasive, safe, simple and practical imaging method, which can provide a new imaging reference for the clinical diagnosis of MPP and the formulation of treatment strategies.

Humans ; Severe Acute Respiratory Syndrome ; diagnosis ; therapy