Endoscopy Artefact Detection by Deep Transfer Learning of Baseline Models.

To visualise the tumours inside the body on a screen, a long and thin tube is inserted with a light source and a camera at the tip to obtain video frames inside organs in endoscopy. However, multiple artefacts exist in these video frames that cause difficulty during the diagnosis of cancers. In this research, deep learning was applied to detect eight kinds of artefacts: specularity, bubbles, saturation, contrast, blood, instrument, blur, and imaging artefacts. Based on transfer learning with pre-trained parameters and fine-tuning, two state-of-the-art methods were applied for detection: faster region-based convolutional neural networks (Faster R-CNN) and EfficientDet. Experiments were implemented on the grand challenge dataset, Endoscopy Artefact Detection and Segmentation (EAD2020). To validate our approach in this study, we used phase I of 2,200 frames and phase II of 331 frames in the original training dataset with ground-truth annotations as training and testing dataset, respectively. Among the tested methods, EfficientDet-D2 achieves a score of 0.2008 (mAPd[Formula: see text]0.6+mIoUd[Formula: see text]0.4) on the dataset that is better than three other baselines: Faster-RCNN, YOLOv3, and RetinaNet, and competitive to the best non-baseline result scored 0.25123 on the leaderboard although our testing was on phase II of 331 frames instead of the original 200 testing frames. Without extra improvement techniques beyond basic neural networks such as test-time augmentation, we showed that a simple baseline could achieve state-of-the-art performance in detecting artefacts in endoscopy. In conclusion, we proposed the combination of EfficientDet-D2 with suitable data augmentation and pre-trained parameters during fine-tuning training to detect the artefacts in endoscopy.

Pregnancy-associated plasma protein A (PAPP-A) to predict adverse fetal outcomes in Chinese: What is the optimal cutoff value?

A low level of PAPP-A predicts adverse fetal outcomes. As Chinese pregnant women have a higher level of PAPP-A, the predictive performance of PAPP-A and its optimal cutoff value might be different. This study aims to establish a PAPP-A cutoff value in the Chinese population that identifies adverse fetal outcomes. We retrospectively analysed 4936 spontaneous singleton pregnancies of Chinese women who underwent first-trimester combined Down's screening in our unit from March 2010 to January 2014 and had delivery information available. A composite adverse fetal outcome encompassed intrauterine fetal loss (including miscarriages and stillbirths), and live births either before 32 weeks or weighing less than -2 standard deviation (SD) for gestation. The area under the curve of the receiver-operator characteristic curve for prediction of the composite adverse outcome using PAPP-A was 0.626 (95% CI =0.612-0.640, p < 0.0001). PAPP-A ≤ 0.23 multiples of median (MoM) identified 0.6% of Chinese pregnant women to be at significant risk of adverse fetal outcome (positive likelihood ratio 11.2, positive predictive value 21.4%) despite a low sensitivity (5.1%, 95% CI =1.9-10.8). The negative predictive value was high (97.7%). The commonly used cutoff of 0.4 MoM was associated with a positive likelihood ratio of 3.7 only. A prospective study is warranted.

Multi-users network model and the corresponding networking scheme for indoor VLC systems.

Recently, the visible light communication (VLC) based on LEDs has attracted much attention. In order to realize multi-users indoor VLC system based on the hybrid full-duplex, we design a kind of illumination/communication terminal and present the corresponding network model in this paper. We propose a multi-access scheme, which can avoid the access collision and network congestion. Meanwhile, we present a method to establish the link between users and expound the routing strategy of information forwarding. Besides, we evaluate the network performance by numerical simulations in aspects of access collision probability, throughput, access time and link establishment time. The results show that the proposed multi-access scheme and routing strategy are feasible for indoor VLC system.

Differences of various region-of-interest methods for measuring dopamine transporter availability using 99mTc-TRODAT-1 SPECT.

This study was to investigate whether various region-of-interest (ROI) methods for measuring dopamine transporter (DAT) availabilities by single photon emission computed tomography (SPECT) are statistically different, whether results of medical research are thereby influenced, and causes of these differences. Eighty-four healthy adults with (99m)Tc-TRODAT-1 SPECT and magnetic resonance imaging (MRI) scans were included. Six major analysis approaches were compared: (1) ROI drawn on the coregistered MRI; (2) ROIs drawn on the SPECT images; (3) standard ROI templates; (4) threshold-ROIs; (5) atlas-based mappings with coregistered MRI; and (6) atlas-based mappings with SPECT images. Using the atlas-based approaches we assessed the influence of striatum ROIs by slice-wise and voxel-wise comparisons. In (5) and (6), three partial-volume correction (PVC) methods were also explored. The results showed that DAT availabilities obtained from different methods were closely related but quite different and leaded to significant differences in determining the declines of DAT availability per decade (range: 5.95-11.99%). Use of 3D whole-striatum or more transverse slices could avoid biases in measuring the striatal DAT declines per decade. Atlas-based methods with PVC may be the preferable methods for medical research.

Effects of metformin on the cerebral metabolic changes in type 2 diabetic patients.

Metformin, a widely used antidiabetic drug, has numerous effects on human metabolism. Based on emerging cellular, animal, and epidemiological studies, we hypothesized that metformin leads to cerebral metabolic changes in diabetic patients. To explore metabolism-influenced foci of brain, we used 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) positron emission tomography for type 2 diabetic patients taking metformin (MET, n = 18), withdrawing from metformin (wdMET, n = 13), and not taking metformin (noMET, n = 9). Compared with the noMET group, statistical parametric mapping showed that the MET group had clusters with significantly higher metabolism in right temporal, right frontal, and left occipital lobe white matter and lower metabolism in the left parahippocampal gyrus, left fusiform gyrus, and ventromedial prefrontal cortex. In volume of interest (VOI-) based group comparisons, the normalized FDG uptake values of both hypermetabolic and hypometabolic clusters were significantly different between groups. The VOI-based correlation analysis across the MET and wdMET groups showed a significant negative correlation between normalized FDG uptake values of hypermetabolic clusters and metformin withdrawal durations and a positive but nonsignificant correlation in the turn of hypometabolic clusters. Conclusively, metformin affects cerebral metabolism in some white matter and semantic memory related sites in patients with type 2 diabetes.

The changes in brain metabolism in people with activated brown adipose tissue: a PET study.

Brown adipose tissue (BAT) is a highly specialized thermogenic tissue and has profound effects on body weight, energy balance, and glucose metabolism. Body temperature regulation depends on the integrated activities of the autonomic nervous system, which is centered predominantly in the hypothalamus. The purpose of this study was to explore the interaction of brain and the activation of BAT by analyzing differences in brain metabolism between patients with and without activated BAT. Fluorodeoxyglucose (FDG) with positron emission tomography/computer tomography (PET/CT) was used to determine the activation of BAT and brain metabolism. After reviewing FDG PET/CT scans, we retrospectively collected 42 patients, 21 with activated BAT and 21 matched controls without activated BAT. We used the method of defining regions of interest (ROI) to examine differences in metabolism between their hypothalami and voxel (volumetric pixel)-based statistical parametric mapping to analyze the whole brain. Compared with controls, patients with activated BAT had a significant hypermetabolic area in the right inferior parietal lobule (Brodmann area 40) and significant hypometabolic areas in the left insula (Brodmann area 13) and right cerebellum; however, there were no metabolic differences in the hypothalamic regions. Our findings illustrate the close relationship of cold temperature exposure-triggered hypermetabolism in the right inferior parietal lobule and activated BAT. They also support the hypotheses that the insula and cerebellum regulate autonomic functions, which are important for controlling BAT thermogenesis within the central pathways.

On the origin of the relative stability of Wells-Dawson isomers: a DFT study of α-, ß-, γ-, α*-, ß*-, and γ*-[(PO4)2W18O54](6-) anions.

Density functional theory calculations have been carried out to investigate α-, ß-, γ-, α*-, ß*-, and γ*-[(PO(4))(2)W(18)O(54)](6-) Wells-Dawson isomers, which exhibited stability in the order of α > ß > γ > γ* > ß* > α*, reproduced the experimental observations (α > ß > γ), and confirmed the hypothesis of Contant and Thouvenot (γ* > ß* > α*). Energy decomposition analysis reveals that both the spatial arrangement of the host W(18)O(54) cage (eclipsed or staggered) and its structural distortion induced by the encapsulated guest anions are two dominant factors in control of the stability order, while the influences of host-guest interaction and distortion of the guest anions are very small. A building block decomposition approach is designed and provides an effective means to clarify the detailed relationship between the local distortion and energy. By using this method, it is found that the eclipsed belt, and in particular the staggered belt, significantly distort the two caps inside the Wells-Dawson structure. Notably, there is a direct relationship between the overall stability and distortion in the belts, which is proven to be partly originating from the dominance in the quantity of the belt building blocks over that of the caps (12:6). Besides, half-unit {XW(9)} decomposition confirms that [(XO(4))(2)W(18)O(54)](n-) (X = Si, Ge, Al, and Ga) are thermodynamically instable because of the notable electrostatic repulsion between two {XW(9)} units induced by the highly charged guest anions.

MoNuSAC2020: A Multi-Organ Nuclei Segmentation and Classification Challenge.

Detecting various types of cells in and around the tumor matrix holds a special significance in characterizing the tumor micro-environment for cancer prognostication and research. Automating the tasks of detecting, segmenting, and classifying nuclei can free up the pathologists' time for higher value tasks and reduce errors due to fatigue and subjectivity. To encourage the computer vision research community to develop and test algorithms for these tasks, we prepared a large and diverse dataset of nucleus boundary annotations and class labels. The dataset has over 46,000 nuclei from 37 hospitals, 71 patients, four organs, and four nucleus types. We also organized a challenge around this dataset as a satellite event at the International Symposium on Biomedical Imaging (ISBI) in April 2020. The challenge saw a wide participation from across the world, and the top methods were able to match inter-human concordance for the challenge metric. In this paper, we summarize the dataset and the key findings of the challenge, including the commonalities and differences between the methods developed by various participants. We have released the MoNuSAC2020 dataset to the public.

On the origin of the inverted stability order of the reverse-Keggin [(MnO4)(CH3)12Sb12O24]6-: a DFT study of alpha, beta, gamma, delta, and epsilon isomers.

Density functional theory calculations have been carried out to investigate the alpha, beta, gamma, delta, and epsilon isomers of [(MnO(4))Me(12)Sb(12)O(24)](6-) (Me = CH(3)) anions, which are simplified Baker-Figgis models of Keggin-type antimonate complexes in experiments. It is found that the stability order of the five isomers (alpha < beta < gamma < delta < epsilon) perfectly reverses to the well-known trend of the classical Keggin [PW(12)O(40)](3-) anions (alpha > beta > gamma > delta > epsilon), despite their significant similarities in frameworks. On the basis of the building block decomposition method, the stabilizing effect of the edge-sharing [Sb(2)(mu-O)(2)Me(2)] fragment inside gamma, delta, and epsilon structures is confirmed and found to originate from its two energy-favorable components rather than itself as an indivisible unit. Similar behavior is also held by the destabilizing [W(2)(mu-O)(2)O(2)] fragment in [PW(12)O(40)](3-); however, the well-accepted electrostatic repulsion between the short W(VI)-W(VI) contacts cannot be taken as direct evidence. Notably, in the assembly of the [(MnO(4))Me(12)Sb(12)O(24)](6-) structure, all of the octahedral building units incline to compress axially and elongate horizontally, and this is exactly opposite to the deformation pattern observed in the building blocks of Keggin tungstates, which tend to elongate axially and compress horizontally, thus giving rise to the inverted stability order. Furthermore, energy decomposition analysis reveals that the intrinsic property of the anion comes from the spatial arrangements of the metal-oxygen cage and does not change significantly with the type and charge of the encapsulated anion.

[Seasonal Characteristics and Source Analysis of Water-soluble Inorganic Ions in PM2.5 in Suqian City].

To study the seasonal pollution characteristics and sources of water-soluble inorganic ions in atmospheric PM2.5 in Suqian City, 171 samples were collected at three monitoring points, which were in the water vapor channel, from May 2017 to January 2018. The mass concentrations of PM2.5 and nine water-soluble inorganic ions were analyzed. The results showed that the annual average concentration of water-soluble inorganic ions in PM2.5 in Suqian City was (44.08±34.61) µg ·m-3, accounting for 41.8% of PM2.5. The concentrations of these species were in the order of ρ(NO3-) > ρ(SO42-) > ρ(NH4+) > ρ(ρl-) > ρ(Na+) > ρ(Ca2+) > ρ(K+) > ρ(F-) > ρ(Mg2+); NO3-, SO42-, and NH4+ accounted for 75.6% of the total water-soluble ions. The annual average ratio of ρ(NO3-) to ρ(SO42-) was 1.53±0.88, indicating that mobile sources contributed more to PM2.5 pollution. Based on the correlation analysis of NH4+ and SO42-, NO3- may exist in the form of (NH4)2 SO4, NH4HSO4, or NH4NO3. According to the principal component analysis, secondary transformation, industrial pollution, biomass burning, and dust were the major sources of water-soluble inorganic ions. PM2.5concentrations were positively related to relative humidity in winter. Water vapor transmission is more likely to promote PM2.5 accumulation in winter.

Evaluation of in vitro embryotoxicity tests for Chinese herbal medicines.

Chinese herbal medicines (CHMs) have been widely used during pregnancy, but feto-embryo safety tests are lacking. Here we evaluated in vitro embryotoxicity tests (IVTs) as alternative methods in assessing developmental toxicity of CHMs. Ten CHMs were selected and classified as strongly, weakly and non-embryotoxic. Three well validated IVTs and prediction models (PMs), including embryonic stem cell test (EST), micromass (MM) and whole embryo culture (WEC), were compared. All strongly embryotoxic CHMs were predicted by MM and WEC PM2. While all weakly embryotoxic CHMs were predicted by MM and WEC PM1. All non-embryotoxic CHMs were classified by EST, MM, but over-classified as weakly embryotoxic by WEC PM1. Overall predictivity, precision and accuracy of WEC determined by PM2 were better than EST and MM tests. Compared with validated chemicals, performance of IVTs for CHMs was comparable. So IVTs are adequate to identify and exclude embryotoxic potential of CHMs in this training set.

Improved neural network based scene-adaptive nonuniformity correction method for infrared focal plane arrays.

An improved scene-adaptive nonuniformity correction (NUC) algorithm for infrared focal plane arrays (IRFPAs) is proposed. This method simultaneously estimates the infrared detectors' parameters and eliminates the nonuniformity causing fixed pattern noise (FPN) by using a neural network (NN) approach. In the learning process of neuron parameter estimation, the traditional LMS algorithm is substituted with the newly presented variable step size (VSS) normalized least-mean square (NLMS) based adaptive filtering algorithm, which yields faster convergence, smaller misadjustment, and lower computational cost. In addition, a new NN structure is designed to estimate the desired target value, which promotes the calibration precision considerably. The proposed NUC method reaches high correction performance, which is validated by the experimental results quantitatively tested with a simulative testing sequence and a real infrared image sequence.

Prediction and analysis of Q-markers of Elephantopus scaber based on its UPLC fingerprint, content determination of components, and in vitro a nti-tumor activity / 中国中药杂志

This study aimed to provide scientific evidence for predicting quality markers(Q-markers) of Elephantopus scaber by establishing UPLC fingerprint of E. scaber from different geographical origins and determining the content of 13 major components, as well as conducting in vitro anti-cancer activity investigation of the main components. The chromatographic column used was Waters CORTECS UPLC C_(18)(2.1 mm×150 mm, 1.6 μm), and the mobile phase consisted of acetonitrile and 0.1% formic acid solution(gradient elution). The column temperature was set at 30 ℃, and the flow rate was 0.2 mL·min~(-1). The injection volume was 1 μL, and the detection wavelength was 240 nm. The UPLC fingerprint of E. scaber was fitted using the Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine(2012 edition) to determine common peaks, evaluate similarity, identify and determine the content of major components. The CCK-8 assay was used to explore the inhibitory effect of the main components on the proliferation of lung cancer cells. The results showed that in the established UPLC fingerprint of E. scaber, 35 common peaks were identified. Thirteen major components, including neochlorogenic acid(peak 1), chlorogenic acid(peak 2), cryptochlorogenic acid(peak 3), caffeic acid(peak 4), schaftoside(peak 6), galuteolin(peak 9), isochlorogenic acid B(peak 10), isochlorogenic acid A(peak 12), isochlorogenic acid C(peak 18), deoxyelephantopin(peak 28), isodeoxyelephantopin(peak 29), isoscabertopin(peak 31), and scabertopin(peak 32) were identified and quantified, and a quantitative analysis method was established. The results of the in vitro anti-cancer activity study showed that deoxyelephantopin, isodeoxyelephantopin, isoscabertopin, and scabertopin in E. scaber exhibited inhibition rates of lung cancer cell proliferation exceeding 80% at a concentration of 10 μmol·L~(-1), higher than the positive drug paclitaxel. These results indicate that the fingerprint of E. scaber is highly characteristic, and the quantitative analysis method is accurate and stable, providing references for the research on quality standards of E. scaber. Four sesquiterpene lactones in E. scaber show significant anti-cancer activity and can serve as Q-markers for E. scaber.

[The direct antiviral effect of interferon-gamma on hepatitis C virus replicon].

OBJECTIVE: To study the effects of interferon-gamma and interferon-gamma combined with interferon-alpha on HCV RNA replication and the possible mediators of interferon-gamma anti-HCV in vitro. METHODS: An HCV replicon cell culture system was established and the cells were treated with interferon-gamma or interferon-gamma combined with interferon-alpha. HCV RNA levels in the cells were evaluated by semi-quantitative RT-PCR and real-time PCR, and the levels of NS5A protein were examined by Western blot. RESULTS: Interferon-gamma could inhibit HCV RNA replication and NS5A protein expression effectively; The anti-HCV effects of interferon-gamma were both in time-dependent and does-dependent manners; Pretreating the cells with interferon-gamma could significantly enhance the antiviral effects of interferon-alpha; The expressions of IRF-1, 2'5'-OAS1(p46), 2'5'-OAS2(p69), ISGF3gamma and STAT1 were significantly increased after interferon-gamma treatment. CONCLUSION: Interferon-gamma has a direct inhibitory effect on HCV replicon RNA replication and NS5A expression, and both are in a dose and time dependent manner; Interferon-gamma has a synergistic anti-HCV effect with interferon-alpha. IRF-1, 2'5'-OAS1(p46), 2'5'-OAS2(p69) and ISGF3gamma may mediate the anti-HCV effects of interferon-gamma.

Indoor Environmental Factors and Occurrence of Lung Function Decline in Adult Residents in Summer in Southwest China.

BACKGROUND: There is conflicting reports on the respiratory health effects of indoor risk factor exposure. The aim of this study was to assess the association of indoor environmental factors to pulmonary function in an adult population in Zunyi City of Southwest China. METHODS: Between July and Sep 2012, we conducted a cross-sectional survey of people aged ≥18 yr in 11 inner-city areas of Zunyi. Data on asthma and asthma-related symptoms and selected home environmental factors were assessed by questionnaire. Lung function measurements, including FVC, FEV1, FEV1/FVC and PEFR, were assessed and compared. Exposure to indoor and outdoor PM2.5 was monitored by measurement of PM2.5 emission relative concentration. RESULTS: Cooking oil fumes, environmental tobacco smoke (ETS) and coal fuel use were associated with impaired lung function among adults in summer season (P<0.05). Subjects exposed coal fuel combustion, cooking oil fumes, pest in kitchen, mosquito repellent, fluffy blanket, pets, visible mold in bedroom and ETS (active and passive smoking) tended to exhibit greater decreases in FVC, FEV1 and PEFR values compared with their non-exposed counterparts (P<0.05). Median PM2.5 relative concentrations in kitchen, sleeping area and outdoor were 486.0cpm, 463.0cpm and 459.0cpm, respectively. PM2.5 relative concentration in indoor kitchen and sleeping area were significant higher than outdoor (P<0.001). CONCLUSION: A negative association between kitchen, sleeping area risk factors and ETS exposure and a reduction in lung function in summer was revealed in Zunyi.

Finite element optimization analysis of minimally invasive screw treatment for Sanders typeⅡcalcaneal fracture / 中国骨伤

OBJECTIVE@#To explore biomechanical characteristics of minimally invasive different screw fixations in treating Sanders typeⅡcalcaneal fractures.@*METHODS@#Dicom data of calcaneus by CT scan were input into Mimics 21.0 software and Ansys15.0 software to construct three-dimensional finite element digital model of calcaneus;this model was input into UG NX 10.0 software, and calcaneus was cut according to Sanders classification to establish Sanders typeⅡ calcaneus model with posterior articular surface collapse;then simulated minimally invasive screw internal fixation after calcaneal fracture:a screw from posterior articular surface was used to outside-in fix sustentaculum tali, other 4 screws were used to fix calcaneus by different methods through calcaneal tuberosity, and 4 different calcaneal models were obtained. Under the same conditions, 4 types of internal fixation models were loaded respectively, and nonlinear finite element analysis was performed to calculate the stress distribution of different internal fixation models.@*RESULTS@#Under the same condition of loading, the model 3 had smaller displacement value, maximum calcaneus displacement value and maximum equivalent stress value of the screw than other three internal fixation models, and the stress was more dispersed.@*CONCLUSION@#In minimally invasive screw internal fixation of calcaneus fracture, after 1 sustentaculum tali screw fixation, 2 screws crossed fix posterior articular surface from calcaneal tuberosity, 2 screws fix parallelly calcaneocuboid joint from calcaneal tuberosity are more suitable for biomechanical requirements, and could provide basic theory for clinical treatment.

Mechanism of nonylphenol-induced neurotoxicity in F1 rats during sexual maturity.

OBJECTIVE: The purpose of this study was to examine whether gestational and lactational exposure to environmental endocrine disrupting chemical, nonylphenol (NP), in pregnant dams would lead to the alterations in hormone levels in the body, apoptosis and glial fibrillary acidic protein (GFAP) in hippocampus during weaning and sexual maturity periods in pups of rats. METHODS: Dams were gavaged with NP at dose levels of 25 mg/kg/day (low dose), 50 mg/kg/day (middle dose), 100 mg/kg/day (high dose) and groundnut oil alone (vehicle control) respectively from gestational day 6 to postnatal day (PND) 21. RESULTS: At PND 21, serum testosterone (TT) level significantly decreased in the 50, 100 mg/kg NP-treated groups compared with the control (p < 0.01). Serum estradiol (E2) level was increased with the increase in the NP concentration; a dose-effect relationship was revealed (r = 0.462, p < 0.01). At both PND 21 and PND 60, pups exposed to 100 mg/kg/day NP had an obviously higher apoptotic rate than control did. We observed a significant positive correlation between the dose of NP and the apoptotic rate (r = 0.836, p < 0.05). The number of GFAP-positive cells in rat hippocampus and integral optical density (IOD) of 100 mg/kg/day NP-treated group were much higher than the control group. GFAP mRNA expressions increased at high dose (100 mg/kg/day) (p < 0.05), and positive correlations between the GFAP mRNA expressions and NP level was observed (r = 0.586, 0.737, p < 0.05). Both the number of growth-associated protein (GAP)-43 positive cells and IOD were much lower at high dose (100 mg/kg/day) than the control at both PND 21 and PND 60 (p < 0.05). The number of GAP-43 positive cells was negatively correlated with the NP exposure dose (r = - 0.562, - 0.649, p < 0.05) at these two time points. GAP-43 mRNA expressions in the hippocampus of pups decreased dramatically at high dose (100 mg/kg/day) at both PND 21 and PND 60 compared with the control (p < 0.05). CONCLUSION: High exposure to NP might inhibit neuronal development and differentiation as indicated by the reduction of the neurotrophic factor GAP-43.

Evaluation of the safety and efficacy of percutaneous radiofrequency ablation for treating multiple breast fibroadenoma.

BACKGROUND: This study was conducted to evaluate the safety and efficacy of ultrasound (US)-guided percutaneous radiofrequency ablation (RFA) for multiple breast fibroadenoma as an alternative to surgical resection. PATIENTS AND METHODS: Sixty-five patients with multiple breast fibroadenoma accepted general anesthesia and US-guided percutaneous RFA in our hospital from September 2014 to January 2016. Contrast-enhanced US (CEUS) was used immediately after operation to determine whether the tumor was ablated completely. The complete ablation rate (CAR) and the change of focal volume were evaluated by CEUS at the 1st month and the 3rd month after operation. RESULTS: All the patients were diagnosed by needle biopsy. Among all the patients, 256 nodules were found. Forty-six nodules (17.96%) were located <5 mm from epidermis; 26 nodules (10.15%) were located below areola. Complete ablation was achieved for 251 nodules (98.04%) after the 1st month of operation. The volume reduce rate was 39.06% and 75.99% at the 1st and the 3rd month after operation, respectively, of which 45 nodules were completely absorbed (17.58%). There was a statistically significant difference of the volume reduction rate (VRR) after operation (P < 0.01) compared with preoperative breast nodules volume. There were no complications such as skin burn, hemorrhage, and hematoma, nipple discharge in the process during and after RFA. CONCLUSION: Given advantages of high CAR, mild injury, rapid recovery, and cosmetic outcome desired by the patients, RFA has the potential to become the preferred method in the treatment of breast fibroadenoma.

[Investigating the inhibitory effects of interferon-alpha on the replication of hepatitis C virus replicon].

OBJECTIVE: To investigate the inhibitory effects of interferon-alpha (IFN-alpha) on HCV replicon and evaluate the expressing levels of signal transducer and activator of transcription genes (STAT1 and STAT2) and IFN-alpha stimulated genes (ISGs) which may mediate the inhibitory effects of IFN-alpha on HCV. METHODS: Firstly HCV replicon cell culture system was established by transfecting HCV replicon RNA transcribed in vitro into Huh7 cells and screening with G418. Secondly, the established HCV replicon cells were treated with various concentrations of IFN-alpha (0, 10, 25, 50, 100, 250, 500, 750, 1000, 2500, and 5000 IU/ml) for 72 h or treated with 1000 IU/ml of IFN-alpha for different lengths of time (0, 24, 48, 72, 96 h), then the levels of HCV RNA and NS5A protein in these cells were examined by semi-quantitative RT-PCR and Western blot respectively. RESULTS: IFN-alpha could effectively inhibit HCV RNA replication. 10 IU/ml or 25 IU/ml of IFN-alpha could lead to about 68% and 75% of HCV-RNA reduction respectively. The cells treated with 1000 IU/ml IFN-alpha for 24 h or 96 h had about 75% and 88% of HCV RNA reduction compared with the cells of control, demonstrated that the inhibitory effects of IFN-alpha on HCV replicon are in dose and time dependent manners. The expressions of antiviral ISGs-PKR, 2'5'OAS, G1P3, ISG20 and ISGF3gamma are strongly induced by IFN-alpha. CONCLUSIONS: HCV replicons were sensitive to IFN-alpha treatment. The inhibitory effects of IFN-alpha on HCV RNA and NS5A are both dose and time dependents. PKR, 2'5'OAS, G1P3, ISG20 and ISGF3gamma may mediate the inhibitory effects of IFN-alpha on HCV replicon replication.