Pre-exposure to 50 Hz-electromagnetic fields enhanced the antiproliferative efficacy of 5-fluorouracil in breast cancer MCF-7 cells.

Resistance to 5-fluorouracil (5-FU) and its induced immune suppression have prevented its extensive application in the clinical treatment of breast cancer. In this study, the combined effect of 50 Hz-EMFs and 5-FU in the treatment of breast cancer was explored. MCF-7 and MCF10A cells were pre-exposed to 50 Hz-EMFs for 0, 2, 4, 8 and 12 h and then treated with different concentrations of 5-FU for 24 h; cell viability was analyzed by MTT assay and flow cytometry. After pre-exposure to 50 Hz-EMFs for 12 h, apoptosis and cell cycle distribution in MCF-7 and MCF10A cells were detected via flow cytometry and DNA synthesis was measured by EdU incorporation assay. Apoptosis-related and cell cycle-related gene and protein expression levels were monitored by qPCR and western blotting. Pre-exposure to 50 Hz-EMFs for 12 h enhanced the antiproliferative effect of 5-FU in breast cancer cell line MCF-7 in a dose-dependent manner but not in normal human breast epithelial cell line MCF10A. Exposure to 50 Hz-EMFs had no effect on apoptosis and P53 expression of MCF-7 and MCF10A cells, whereas it promoted DNA synthesis, induced entry of MCF-7 cells into the S phase of cell cycle, and upregulated the expression levels of cell cycle-related proteins Cyclin D1 and Cyclin E. Considering the pharmacological mechanisms of 5-FU in specifically disrupting DNA synthesis, this enhanced inhibitory effect might have resulted from the specific sensitivity of MCF7 cells in active S phase to 5-FU. Our findings demonstrate the enhanced cytotoxic activity of 5-FU on MCF7 cells through promoting entry into the S phase of the cell cycle via exposure to 50 Hz-EMFs, which provides a novel method of cancer treatment based on the combinatorial use of 50 Hz-EMFs and chemotherapy.

[A technique analysis for dissection of anterolateral thigh perforator flap].

Objective: To improve the harvesting techniques of anterolateral thigh perforator flap, and to reduce the operation time. Methods: Between January 2008 and June 2015, 400 patients undergoing repair with anterolateral thigh perforator flap were included to analyze the technical factors, including 370 cases (92.5%) obtaining primary healing and 30 cases (7.5%) receiving re-exploration. Combined with the literature, a modified flap dissection was made: reverse tracing and sequential dissection of the descending branch of the lateral circumflex femoral artery. Between June 2015 and June 2016, the modified free anterolateral thigh perforator flap was used in 100 cases. Of 100 cases, 76 were male and 24 were female, aged from 11 to 71 years (mean, 35.6 years). The wound size ranged from 8 cm×5 cm to 23 cm×9 cm. The time between injury and surgery ranged from 5 to 31 days (mean, 14.3 days). Results: The operation time of modified flap dissection was reduced to (30.1±19.3) minutes from (85.0±30.2) minutes (unmodified flap dissection). Postoperatively, 94 flaps survived uneventfully, and incision healed by first intention. Six flaps received re-exploration surgery because of vascular compromise; the flap survived after removal of thrombosis in 4 cases of vein thrombosis; the flap necrosed in 2 cases of vein and artery thrombosis, and skin grafting was performed. Ninety-four patients whose flaps survived were followed up 3-12 months (mean, 6.3 months); the flaps had good color and appearance, and second stage operation was performed to make the flap thinner in 21 cases. Conclusion: Improved harvesting technique of free anterolageral thigh perforator flap could decrease surgery time and difficulty in dissection.

[Clinical features and proportion analysis of adult hip fractures at 11 hospitals in Southwest China from 2010 to 2011].

OBJECTIVE: To analyze the clinical feature and constituent ratio of adult hip fractures in Southwest China. METHODS: The data of adult inpatients and outpatients with hip fractures treated between January 2010 and December 2011 in 11 hospitals of the Southwest China were collected and analyzed. The data includes gender, age, age distribution and fracture pattern according to AO classification. RESULTS: There were a total of 2,833 adult hip fractures, including 1,340 (47.30%) males and 1,493 (52.70%) females, with a male-to-female incidence ratio of 1: 1.11 and a mean age of (66±18) years. The highest frequency of hip fractures was seen in the 71 to 85 years age group (42.18%, 1,195/2,833). There were 844 fractures (29.79%) in the young and middle-aged group (16-<60 years) and 1 898 fractures (70.21%) in the geriatric group (≥60 years). Men had a higher rate than women (men: 577 fractures, 68.4%) in the young and middle-aged group, while women had a higher rate than men (women: 1,226 fractures, 61.64%) in the geriatric group, with a significant difference in the sex distribution between the two groups (χ2=214.001, P<0.01). The proportion of intertrochanteric fracture (type 31-A), femoral neck (type 31-B) and femoral head fracture (type 31-C) was 46.59%, 49.74% and 3.67% respectively. The highest frequency of the sub-type in each fracture type was type 31-A2, type 31-B2 and type 31-C2. CONCLUSIONS: Women have a higher rate than men in Southwest China. Geriatric patients are more than the young and middle-aged patients. The femoral neck fractures, intertrochanteric fractures and femoral head fractures are in descending orders according to the proportion of the three different hip fractures.

Effect of scattering angle error on particle size determination by multiangle dynamic light scattering.

Dynamic light scattering (DLS) is a popular method of particle size measurement. Multiangle dynamic light scattering (MDLS) collects DLS data at multiple angles and analyzes the data simultaneously to improve the particle size measurement. Using data from several scattering angles admits the possibility of introducing noise caused by scattering angle error in the measurement, which may have an impact on the performance of the MDLS technique. We investigate the effect of scattering angle noise on recovered particle size distributions (PSDs) using simulated and measured MDLS data and various levels of angular noise. Our results show that, for unimodal PSDs, those with small particle sizes are more strongly affected by the noise than are medium and large particle size systems. For bimodal PSDs, those containing small-sized particles are also more affected by the noise than the systems of larger particles. Furthermore, broad PSDs are more vulnerable to angular noise than narrow PSDs.

Analysis of noisy multi-angle dynamic light scattering data.

In multi-angle dynamic light scattering measurements, due to the inevitable presence of baseline measurement noise, the normalized intensity autocorrelation function (ACF) data deviates from the true value. This leads to incorrect angular weighting estimates, which affect the accuracy of inversion results and determination of particle size distributions (PSDs). We outline a method to calculate better angular weighting coefficients from the noisy intensity ACF data. The method involves first compensating for the baseline error in the ACF data and then determining the weighting coefficients. We demonstrate the method using simulated ACF data containing baseline error for unimodal and bimodal PSDs and also for experimental data for unimodal and bimodal samples. For the unimodal PSDs ACF data were simulated for 100-900 nm and 100-650 nm particle size ranges, and for bimodal PSDs 360-900 nm and 100-900 nm particle size ranges were used. The performance of our method was shown by comparing the results of weighting coefficient and PSD determination with and without baseline compensation to the known coefficient values and PSDs. With baseline compensation the relative error of the weighting coefficients decreased significantly. Furthermore, with baseline compensation, the PSD results for the four groups of simulated data were improved. The deviations between the known and recovered PSDs were decreased, the relative error of peak position obviously decreased, and the occurrence of false peaks was reduced. The PSD results from the experimental data further validates the conclusion that the method proposed apparently reduces the relative error of peak position, effectively eliminates the false peak, and improves the accuracy of the recovered PSD.

[Effect of different volumes of fluid resuscitation on hemorrhagic shock with pulmonary edema at high altitude in the unacclimated rat].

OBJECTIVE: To study the effects of different volumes of fluid resuscitation on hemorrhagic shock with pulmonary edema at high altitude in the unacclimated rat. METHODS: One hundred and twenty-six SD rats transported to Lasa, Tibet, 3 760 meters above the sea level, were anesthetized one week later with sodium pentobarbital (30 mg/kg, intraperitoneal). Hemorrhagic shock with pulmonary edema model was induced by hemorrhage (50 mm Hg for 1 hour, 1 mmHg=0.133 kPa) plus intravenous injection of oleic acid (50 microl/kg). Experiments were then conducted in two parts. Sixty-three rats in part I were equally divided into nine groups (n=7): normal control, hemorrhagic shock control, hemorrhagic shock with pulmonary edema (HSPE) without fluid infusion, HSPE plus infusing lactated Ringer's solution (LR) with 0.5-, 1-, 1.5-, 2- or 3- fold volume shed blood, and 1 volume of LR plus mannitol (10 ml/kg). Hemodynamic parameters including mean arterial blood pressure (MAP), left intraventricular systolic pressure (LVSP) and the maximal change rate of intraventricular pressure rise or decline (+/- dp/dt max) were observed at 15, 30, 60 and 120 minutes after infusion, blood gases were measured at 30 and 120 minutes after infusion and the water content of lung and brain was determined at 120 minutes after infusion. In part II, additional 63 rats were used to observe the effect of different volumes of fluid resuscitation on survival time of HSPE rats. RESULTS: 0.5 volume of LR infusion significantly improved MAP, LVSP and +/- dp/dt max, prolonged the survival time of HSPE animals (all P<0.01), while it did not increase the water content of lung and brain and had no marked influence on blood gases. One volume of LR infusion slightly improved hemodynamic parameters, prolonged the survival time and increased the water content of lung. More than 1 volume of LR infusion including 1.5-, 2- and 3- fold volume LR deteriorated the hemodynamic parameters and decreased the survival time of shocked animal, meanwhile they apparently increased the water content of lung. One volume of LR plus mannitol (10 ml/kg) infusion did not improve the hemodynamic parameters and blood gases; also it did not decrease the water content of lung. CONCLUSION: The tolerance to fluid infusion for the unacclimated animal subjected to hemorrhagic shock with pulmonary edema at high altitude is significantly decreased. 0.5-1 volume of LR infusion appears to be beneficial effect on resuscitation at high altitude, while over 1 volume of LR infusion would aggravate pulmonary edema and exacerbate fluid resuscitation effect.