Safety and efficacy of lumen-apposing metal stents and double-pigtail plastic stents for endoscopic ultrasound-guided drainage of walled-off necrosis; a systematic review and meta-analysis.

BACKGROUND: Patients with walled-off necrosis (WON) are still challenging to treat safely and effectively. Recently, double-pigtail plastic stents (DPS), bi-flanged metallic stents (BFMS), and lumen-apposing metal stents (LAMS) have been employed with endoscopic ultrasound-guided (EUS-guided) drainage. However, there is little solid evidence to support the effectiveness and safety of using stents. This study aims to compare the outcomes of the LAMS and the PS. METHOD: Till July 2022, a thorough database search was done, and studies that met the criteria were chosen. By using the RevMan software, the technical and clinical success and other secondary outcomes were calculated. Subgroup analysis was performed between the LAMS and the BFMS. RESULTS: Fifteen studies (two randomized controlled trials and thirteen observational) with 687 patients receiving metal stents and 771 patients receiving plastic stents were selected for final analysis. There was no significant risk of bias or publication bias. The odds ratios (OR) for technical and clinical success were 0.36 (95% confidence interval (95% CI) 0.08, 1.52) and 2.26 (95%CI 1.62, 3.15), respectively. The OR for overall adverse events was 0.74 (95% CI 0.41, 1.34). In subgroup analysis, the LAMS and the BFMS showed the same outcomes. CONCLUSION: Compared to DPS, LAMS had better clinical outcomes and fewer side effects when treating patients with WON.

What is the best endoscopic treatment option for the walled-off necrosis (WON)?A brief comparison of lumen-apposing metal stents (LAMS), bi-flanged metallic stents (BFMS) and double-pigtail plastic stents (DPS) for the treatment of WON patients.How can we limit the adverse events and provide better treatment.

A nonlocal spectral similarity-induced material decomposition method for noise reduction of dual-energy CT images / 南方医科大学学报

OBJECTIVE@#To propose a nonlocal spectral similarity-induced material decomposition network (NSSD-Net) to reduce the correlation noise in the low-dose spectral CT decomposed images.@*METHODS@#We first built a model-driven iterative decomposition model for dual-energy CT, optimized the objective function solving process using the iterative shrinking threshold algorithm (ISTA), and cast the ISTA decomposition model into the deep learning network. We then developed a novel cost function based on the nonlocal spectral similarity to constrain the training process. To validate the decomposition performance, we established a material decomposition dataset by real patient dual-energy CT data. The NSSD-Net was compared with two traditional model-driven material decomposition methods, one data-based material decomposition method and one data-model coupling-driven material decomposition supervised learning method.@*RESULTS@#The quantitative results showed that compared with the two traditional methods, the NSSD-Net method obtained the highest PNSR values (31.383 and 31.444) and SSIM values (0.970 and 0.963) and the lowest RMSE values (2.901 and 1.633). Compared with the datamodel coupling-driven supervised decomposition method, the NSSD-Net method obtained the highest SSIM values on water and bone decomposed results. The results of subjective image quality assessment by clinical experts showed that the NSSD-Net achieved the highest image quality assessment scores on water and bone basis material (8.625 and 8.250), showing significant differences from the other 4 decomposition methods (P < 0.001).@*CONCLUSION@#The proposed method can achieve high-precision material decomposition and avoid training data quality issues and model unexplainable issues.

Performance of low-dose CT image reconstruction for detecting intracerebral hemorrhage: selection of dose, algorithms and their combinations / 南方医科大学学报

OBJECTIVE@#To investigate the performance of different low-dose CT image reconstruction algorithms for detecting intracerebral hemorrhage.@*METHODS@#Low-dose CT imaging simulation was performed on CT images of intracerebral hemorrhage at 30%, 25% and 20% of normal dose level (defined as 100% dose). Seven algorithms were tested to reconstruct low-dose CT images for noise suppression, including filtered back projection algorithm (FBP), penalized weighted least squares-total variation (PWLS-TV), non-local mean filter (NLM), block matching 3D (BM3D), residual encoding-decoding convolutional neural network (REDCNN), the FBP convolutional neural network (FBPConvNet) and image restoration iterative residual convolutional network (IRLNet). A deep learning-based model (CNN-LSTM) was used to detect intracerebral hemorrhage on normal dose CT images and low-dose CT images reconstructed using the 7 algorithms. The performance of different reconstruction algorithms for detecting intracerebral hemorrhage was evaluated by comparing the results between normal dose CT images and low-dose CT images.@*RESULTS@#At different dose levels, the low-dose CT images reconstructed by FBP had accuracies of detecting intracerebral hemorrhage of 82.21%, 74.61% and 65.55% at 30%, 25% and 20% dose levels, respectively. At the same dose level (30% dose), the images reconstructed by FBP, PWLS-TV, NLM, BM3D, REDCNN, FBPConvNet and IRLNet algorithms had accuracies for detecting intracerebral hemorrhage of 82.21%, 86.80%, 89.37%, 81.43%, 90.05%, 90.72% and 93.51%, respectively. The images reconstructed by IRLNet at 30%, 25% and 20% dose levels had accuracies for detecting intracerebral hemorrhage of 93.51%, 93.51% and 93.06%, respectively.@*CONCLUSION@#The performance of reconstructed low-dose CT images for detecting intracerebral hemorrhage is significantly affected by both dose and reconstruction algorithms. In clinical practice, choosing appropriate dose level and reconstruction algorithm can greatly reduce the radiation dose and ensure the detection performance of CT imaging for intracerebral hemorrhage.

Low-dose helical CT projection data restoration using noise estimation / 南方医科大学学报

OBJECTIVE@#To build a helical CT projection data restoration model at random low-dose levels.@*METHODS@#We used a noise estimation module to achieve noise estimation and obtained a low-dose projection noise variance map, which was used to guide projection data recovery by the projection data restoration module. A filtering back-projection algorithm (FBP) was finally used to reconstruct the images. The 3D wavelet group residual dense network (3DWGRDN) was adopted to build the network architecture of the noise estimation and projection data restoration module using asymmetric loss and total variational regularization. For validation of the model, 1/10 and 1/15 of normal dose helical CT images were restored using the proposed model and 3 other restoration models (IRLNet, REDCNN and MWResNet), and the results were visually and quantitatively compared.@*RESULTS@#Quantitative comparisons of the restored images showed that the proposed helical CT projection data restoration model increased the structural similarity index by 5.79% to 17.46% compared with the other restoration algorithms (P < 0.05). The image quality scores of the proposed method rated by clinical radiologists ranged from 7.19% to 17.38%, significantly higher than the other restoration algorithms (P < 0.05).@*CONCLUSION@#The proposed method can effectively suppress noises and reduce artifacts in the projection data at different low-dose levels while preserving the integrity of the edges and fine details of the reconstructed CT images.

An adaptive CT metal artifact reduction algorithm that combines projection interpolation and physical correction / 南方医科大学学报

OBJECTIVE@#To propose an adaptive weighted CT metal artifact reduce algorithm that combines projection interpolation and physical correction.@*METHODS@#A normalized metal projection interpolation algorithm was used to obtain the initial corrected projection data. A metal physical correction model was then introduced to obtain the physically corrected projection data. To verify the effectiveness of the method, we conducted experiments using simulation data and clinical data. For the simulation data, the quantitative indicators PSNR and SSIM were used for evaluation, while for the clinical data, the resultant images were evaluated by imaging experts to compare the artifact-reducing performance of different methods.@*RESULTS@#For the simulation data, the proposed method improved the PSNR value by at least 0.2 dB and resulted in the highest SSIM value among the methods for comparison. The experiment with the clinical data showed that the imaging experts gave the highest scores of 3.616±0.338 (in a 5-point scale) to the images processed using the proposed method, which had significant better artifact-reducing performance than the other methods (P < 0.001).@*CONCLUSION@#The metal artifact reduction algorithm proposed herein can effectively reduce metal artifacts while preserving the tissue structure information and reducing the generation of new artifacts.

Systematic evaluation of COVID-19 related Internet health rumors during the breaking out period of COVID-19 in China.

Background: To adapt the scientific evaluation tool for the confusion evaluation of health rumors and to test this tool to the confusion evaluation of coronavirus disease 2019 (COVID-19)-related health rumors on Chinese online platforms during the outbreak period of COVID-19in China. Methods: The design of our study was systematic evaluation of COVID-19-related health rumors. Retrieved from 7 rumor-repellent platforms, rumors about COVID-19 were collected during the publication from December 1, 2019, to February 6, 2020, and their origins were traced. Researchers evaluated rumors using the confusion evaluation tool in 6 dimensions(creators, evidence selection, evidence evaluation, evidence application, backing and publication platform, conflict of interest). Items were scored using a seven-point Likert scale. The scores were converted into percentages, and the median of rumors from different sources was compared with rank-sum test. Results: Our research included 127 rumors. Scores were converted to percentages, median and interquartile range are used to describe the data. The median score: creators 25.00%(interquartile range, IQR, 16.67-37.50%), evidence selection 27.78% (IQR, 13.89-44.44%),evidence evaluation 33.33% (IQR, 25.00-45.83%), evidence application 36.11% (IQR, 22.22-47.22%), backing and publication platform 8.33% (IQR, 4.17-20.83%), conflict of interest75.00% (IQR, 50.00-83.33%). Almost 40% rumors came from WeChat and the rumors with the lowest scores were concentrated on the WeChat platform. The rumors about prevention methods have relatively lower scores. Conclusion: Most rumors included were not highly confusing for evaluators of this project.WeChat is the "worst-hit area" of COVID-19 related health rumors. More than half rumors focus on the description of prevention methods, which reflects the panic, anxiety and blind conformity of the public under public health emergencies.

Investigating the intention to receive the COVID-19 vaccination in Macao: implications for vaccination strategies

ImportanceUnderstanding the intention of receiving COVID-19 vaccines is important for informing effective vaccination strategies especially for areas with low incidence. ObjectiveThis study aimed to investigate the intention to receive COVID-19 vaccination, identify the key influencing factors, and determine the most important intention predictors using a theoretically principled model. Design, setting, and participantsThis was a cross-sectional online survey study hosted by Survey Monkey and implemented for 10 days from May 14 2021. People who aged 18 years or above and had been residing in Macao for 12 months prior to the study were recruited through social media. Main outcomes and measuresIntention, the constructs of protection motivation theory (perceived severity, perceived susceptibility, maladaptive response reward, self-efficacy, response-efficacy, and response cost), constructs of health belief model (cues to action), social attitude, social norm, past experience and information seeking behavior, in addition to demographic variables. ResultsOf the 552 respondents, 79.5% aged between 25 and 54 years old, 59.4% were female, and 88% had a bachelor degree or above. Overall, 62.3% of the respondents indicated their intention while 19.2% were hesitant and 18.5% did not have any intention. While 67.0% believed COVID-19 infection was life-threatening, only 19.0% thought they were at risk. Control variables such as age, gender, education level, and having travel plans were significantly correlated with intention. Significant associations were found between intention and all the measures (p<0.05). The most important positive predictors of intention were "being able to make arrangement to receive the vaccine" ({beta} = 0.333, P <0.001), "a sense of social responsibility" ({beta} = 0.326, P < 0.001), and "time off from work after vaccination" ({beta} = 0.169, P <0.001), whereas "concerns over vaccine safety" ({beta} = - 0.124, P < 0.001) and "relying on online resources for vaccine information" ({beta} = -0.065, P <0.05) were negative predictors. Perceived severity was not a predictor of intention. Conclusion and relevanceMulti-component strategies that address various factors affecting intention are needed to formulate effective interventions. Health literacy, vaccination convenience, social responsibility, reasonable incentives and well-informed risk and benefit analysis are recommended consideration for future vaccination campaigns. Key PointsO_ST_ABSQuestionC_ST_ABSWhat is the intention to receive COVID-19 vaccination in Macao and the influencing factors? FindingsA cross-sectional study involving 552 respondents found that the intention rate of COVID-19 vaccination was 62.3% in Macao. Positive predictors of intention included being able to make arrangement to receive the vaccine, a sense of social responsibility, and an offer of time off from work after vaccination. Concerns over vaccine safety and relying on online resources for vaccine information were negative predictors. MeaningIntention to receive COVID-19 vaccination is multifactorial requiring multi-component strategies to promote vaccine uptake.

Regulation of RDN on Th1/ILC1 cell imbalance in HFMD patients caused by EV71 infection / 中国天然药物

Enterovirus 71 (EV71) infection is more likely to cause hand, foot and mouth disease (HFMD) in children, which can lead to neurogenic complications and higher mortality. As a commonly used clinical medicine, Reduning injection (RDN) helps to shorten the symptoms of patients with HFMD and facilitate the early recovery of children. However, the regulatory mechanism of RDN on the HFMD immune system disorder caused by EV71 remains to be discussed. This study collected detailed treatment data of 56 children with HFMD who entered the affiliated Children's Hospital of Nanjing Medical University during 2019. Retrospective analysis of clinical data showed that the symptoms of the RDN treatment group were improved compared with the untreated group. To explore its mechanism, the relevant detection indicators were detected by flow cytometry, enzyme-linked immunosorbent assay and real-time quantitative PCR. It was found that the number and function of innate immune (ILCs) and adaptive immunity (Th1, Th2 and secreted cytokines) were reduced, suggesting that RDN plays a role by regulating cellular immunity. The in vitro differentiation inhibition test further confirmed that RDN affected Th1 differentiation by inhibiting the expression of transcription factors on the basis of Th1 cell differentiation in vitro.

A Pitfall in HbA1c Testing Caused by Hb Long Island Hemoglobin Variant.

BACKGROUND: Although many factors may interfere with hemoglobin (Hb)A1c measurement, Hb variants are among the most important factors. METHODS: We tested the HbA1c levels of the patient, a 32 year old Manchu Chinese woman, during a routine health check. We used different methods, including high-performance liquid chromatography (HPLC) and capillary electrophoresis, to test specimens from the patient. Next, we tested the specimen further using polymerase chain reaction (PCR) and sequencing. RESULTS: We discovered that our patient, who had an HbA1c value of 0, also has an Hb variant, Hb Long Island, which we found during the HbA1c analysis as part of her routine health check at the Health Management Center in the General Hospital of Tianjin Medical University, Tianjin, China. Also, we discovered that the exon 1 of ß gene contained transversion mutations, with 1 heterozygous and 1 homozygous variant (HBB:c.8A > C, 9T > C). These gene mutations resulted in an amino-acid change (His to Pro) and a decrease in HbA1c value. CONCLUSIONS: When there is no correlation between the clinical signs, glycemic status, and glycated Hb levels of the patient, the chromatogram of HbA1c should be carefully checked to detect possible variants that cause interference in the measurement.

Preparation and in vitro release rate of trichosanthes sustained-release pellets / 国际药学研究杂志

Objective: To prepare Trichosanthes sustained-release pellets and investigate its in vitro release. Methods: Trichosanthes sustained-release pellets were prepared by fluid-bed coating technique.The preparation process of its drug loading layer was optimized by orthogonal experiment with binder, solvent, drug loading and creeping speed of peristaltic pump as the factors of investigation and the yield as the investigation index. The optimum prescription and preparation of the pellets were optimized by single factor test with the content of coating material EC, the amount of poreforming agent PEG4000, the amount of talc powder, the coating weight and the curing time as the factors of investigation and the in vitro release as the investigation index. The in vitro release of the pellets was investigated by high performance liquid chromatography with 3, 29-Diphenyl of Trichosanthes Kirilowii Triol(3, 29-DK)as the detection index. Results: The optimum preparation technology of the drug loading layer was 5% binder, 60% ethanol, 35% drug loading and 0.3 r/min peristaltic velocity of fluid-bed peristaltic pump. The optimum preparation technology of sustained-release layer was 5% EC, 1.5% PEG 4000, 1.25% talc powder, 10% weight gain of coating and 6 h curing. Conclusion: The Tricho- santhes sustained-release pellets prepared in this study were released smoothly. Its production method was simple and easy for operation.

Relationship of small non-coding RNA in the seminal plasma with male infertility: An update / 中华男科学杂志

The incidence of male infertility is increasing year by year, but there is a lack of non-invasive accurate diagnostic indicators for this disease, and the pathogenesis of idiopathic infertility is not yet fully clarified. Recent studies have found that there are various small non-coding RNAs (sncRNA) in the human seminal plasma and spermatic exosomes, which can be used as a novel non-invasive biomarker of male infertility. This review outlines the latest research updates on the relationship between sncRNAs in the seminal plasma and male infertility, aiming to provide some new ideas for the screening of the molecular markers of male infertility and study of its underlying molecular mechanisms.

Anti-platelet aggregation and anti-thrombotic mechanism of Trichosanthis Fructus combined with aspirin based on network pharmacology / 中国中药杂志

To explore the anti-platelet aggregation and anti-thrombotic mechanisms of Trichosanthis Fructus combined with aspirin based on network pharmacology and the validation of arteriovenous by pass model in rats. The databases of Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP),Drug Repositioning and Adverse Drug Reaction Chemical-Protein Interactome(DRAR-CPI),Universal Protein Resource(Uniprot) and the Database for Annotation,Visualization,and Integrated Discovery(DAVID) were used to predict protein targets and analyze biological pathway and signal pathway in the combination of Trichosanthis Fructus with aspirin. The effects of pretreatment with Trichosanthis Fructus pellets,aspirin pellets and their combination on thromboxane B2(TXB2),6-keto prostaglandin F1α(6-keto-PGF1α) and cyclic adenosine monophosphate(c AMP) in rat thrombotic model were studied. Through the study of network pharmacology,12 components of aspirin and Trichosanthis Fructus,including hydroxygenkwanin,quercetin and adenosine,were found to show the anti-platelet aggregation and anti-thrombosis mechanisms through9 common protein targets,such as SRC,RAC1,MAPK14,MAPK1,AKT1,and 14 common signaling pathways,such as VEGF signaling pathway. After the intervention with Trichosanthis Fructus pellets combined with aspirin pellets,the vascular endothslia growth factor(VEGF) signaling pathway can be activated to inhibit platelet aggregation and improve vascular endothelial function,and show the anti-platelet aggregation and anti-thrombosis mechanisms,which verify the results of the network pharmacology,and explain the anti-platelet aggregation and anti-thrombotic mechanisms of the combination of Trichosanthis Fructus pellets with aspirin pellets.

Screening and validation of antithrombotic effective components group from Trichosanthes extract / 药学学报

To screen the antithrombotic effective components group of Trichosanthes extract, and to verify its pharmacodynamics and analyze its mechanism, the HPLC fingerprint of Trichosanthes extract (0.09, 0.45, 0.9 g·kg-1) was established, and the pharmacodynamic indexes of antithrombosis in rats with aspirin (0.01 g·kg-1) as positive control group were determined (the animals used in this experiment were approved by the Medical Ethics Committee of Wannan Medical College). The antithrombotic spectrum-activity relationship of Trichosanthes extract was studied and the effective antithrombotic ingredients group was screened by grey relational analysis. The monomer compound mixed solution (0.006, 0.03, 0.06 g·kg-1) was prepared according to the content of each component in the active component group, and the pharmacodynamics and action mechanism were studied to verify the correctness of the spectrum-effect relationship. The correlation between the 22 components of Trichosanthes extract and antithrombotic efficacy was different and showed dose-effect relationship. Cytosine, uracil, guanine, hypoxanthine, xanthine, adenine, guanosine, and adenosine are the main antithrombotic components of Trichosanthes extract. The ratio of cytosine, uracil, guanine, hypoxanthine, xanthine, adenine, guanosine and adenosine was 3∶12∶10∶5∶2∶8∶13∶14. Compared with the model group, the thrombus dry weight of each effective components group could be effectively reduced (P<0.01 or P<0.05), but there was no significant difference between each effective components group and the Trichosanthes extract group. Compared with the model group, the TXB2 content in group (0.06 g·kg-1, 0.03 g·kg-1) could be effectively reduced (P<0.01 or P<0.05), and the content of 6-keto-PGF1α could be increased in each group (P<0.01), and the TXB2/6-keto-PGF1α tended to be normal and showed a dose-effect relationship. The effect was better than that in the Trichosanthes extract group (0.45 g·kg-1) (P<0.01). The effective ingredients group has a good antithrombotic effect, its mechanism is to inhibit platelet aggregation and improve vascular endothelial function.

Development and application of competitive light-initiated chemiluminescent assay for quantitation of total IgE in human serum / 临床检验杂志

Objective To develop a competitive immunoassay for quantitative determination of total immunoglobin E (tIgE) in human serum based on light-initiated chemiluminescent assay (LICA).Methods The LICA-tIgE assay was performed by incubating serum samples or calibrator with anti-human IgE antibody-coated chemiluminescet beads,biotinylated human IgE and streptavidin-coated sensitizer beads.The working conditions of this assay were optimized,analytical performance was detected and the correlation of tIgE results between LICA and Beckman Coulter IMMAGE 800 was evaluated.Results The precision of intra-assay and inter-assay (coefficient of variation) ranged from 5.50％ to 7.73％ and 6.45％ to 9.90％,respectively.The functional sensitivity of this assay was 12.65 IU/mL.The recovery rates measured by adding IgE calibrators to human sera with different IgE concentrations were ranged from 104.15％ to 109.37％.The disturbing rates measured by adding total bilirubin,hemoglobin and triacylglycerol to human sera with different IgE concentrations were ranged from-4.49％ to 8.46％.Also,the tIgE results of 111 patients measured by LICA correlated well with those by Beckman Coulter IMMAGE 800 (r2 =0.959).Conclusion LICA developed in this study for detecting tIgE of human serum showed effective perfomance and could meet the basic requirements of clinical diagnostic reagents.

How to reduce health expenses by using Traditional Chinese Medicine(TCM)? Based on the analysis of inpatients' TCM expenses and typical diseases in Ningxia Province / 中国卫生政策研究

Objective The objective of this paper is to statistically analyze what influence can the utilization of Traditional Chinese Medicine (TCM) have on healthcare expenses of inpatients, and to investigate whether TCM has an advantage of reducing healthcare expenses among certain diseases.Method: Inpatient medical records from 13 public general hospitals in Ningxia Hui autonomous region were collected to set up a database.A multiple linear regression models was established and used to analyze the impact of using TCM on hospitalization expenses.Results: The findings have shown that inpatients who apply TCM have significantly higher hospitalization expenses, with an estimated average of ?8 276.24, while those who do not apply TCM in their treatment spend ?7 254.59 on average (P=0.000).When the proportion of TCM expense higher than 10% of total drug expense, inpatients who apply the TCM have lower hospitalization expenses.In addition, hospitalization expenses decrease with the increase of TCM proportion.Among the diseases of the ear and mastoid disease, diseases of the circulatory system, and certain conditions originating in the perinatal period, inpatients who apply TCM have significant lower hospitalization expense (P=0.000).Hospitalization expense of inpatients who do not apply TCM is twice as much as that of those who apply TCM in the treatment of among diseases of the circulatory system, which has the largest TCM proportion.Conclusion: Only when applying TCM as main therapy can provide price advantage of TCM in the circulatory system caused by chronic diseases, and other advantages of treatment.

Analysis of outpatients' prescriptions utilization of Chinese Patent Medicines in primary health institutions from rural western China / 中国卫生政策研究

Objective: This study aims to analyze the outpatient prescriptions in primary rural health institutions in western China to reveal the feature and disadvantages of utilization of Chinese patent medicines in rural areas.Methods: A total of 14336 prescriptions were selected from 132 health institutions in rural areas of 7 provinces in western China in 2011.The utilization of Chinese patent medicines is described and compared to the health institutions in different levels and different provinces/autonomous regions.Results: The prescriptions of Chinese patent medicines accounted for 62.47% of the total prescriptions in rural health facilities.The proportion of county, township and village medical institutions was 49.76%, 56.96% and 71.51% respectively.86.84% of the Chinese patent medicines prescriptions were prescribed by physicians without traditional Chinese medicine background, while only 13.16% of them were traditional Chinese medicine physicians.The number of varieties of Chinese patent medicines in a single prescription in county, township and village health institutions were 1.38, 1.91 and 2.54, respectively and the average drug costs of every prescription in these health institutions were 52.20 yuan, 21.89 yuan and 19.37 yuan, respectively.Conclusions: There are differences in the utilization of Chinese patent medicines in outpatient prescriptions of rural health institutions in western China.The hospitals in higher medical level use more Chinese patent medicines.The drug cost of the prescription of county health institutions is higher than that of township and village hospitals.This study suggests that health policy should be adjusted based on the specific needs and characteristics of rural health institutions at a different level and should be implemented in the management of prescription in quality control.

Influence of projection data correction on digital breast tomosynthesis imaging / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of detector performance during digital breast tomography (DBT) projection data acquisition on reconstructed image quality.</p><p><b>METHODS</b>With reference to the traditional detector data correction method and the specific data acquisition pattern in DBT imaging, we utilized dark field correction, light field and its gain correction for processing the projection data collected by the detector. The reconstructed images were evaluated using iterative reconstruction method based on total generalized variation (TGV).</p><p><b>RESULTS</b>In physical breast phantom experiment, the proposed method resulted in a reduced Heel effect caused by nonuniform photon number. The reconstructed DBT images after correction showed obviously improved image quality especially in the details with a low contrast.</p><p><b>CONCLUSION</b>The dark field correction, light field and its gain correction process for DBT image reconstruction can improve the image quality.</p>

Sinogram restoration for low-dose cerebral perfusion CT images / 南方医科大学学报

In clinical cerebral perfusion CT examination, repeated scanning the region of interest in the cine mode increases the radiation dose of the patients, while decreasing the radiation dose by lowering the scanning current results in poor image quality and affects the clinical diagnosis. We propose a penalized weighted least-square (PWLS) method for recovering the projection data to improve the quality of low-dose cerebral perfusion CT imaged. This method incorporates the statistical distribution characteristics of brain perfusion CT projection data and uses the statistical properties of the projection data for modeling. The PWLS method was used to recover the data, and the Gauss-Seidel (GS) method was employed for iterative solving. Adaptive weighting is introduced between the original projection data and the projection data after PWLS restoration. The experimental results on the clinical data demonstrated that the PWLS-based sinogram restoration method improved noise reduction and artifact suppression as compared with the conventional noise reduction methods, and better retained the edges and details to generate better cerebral perfusion maps.

Motion-compensated compressed sensing four-dimensional cone-beam CT reconstruction / 南方医科大学学报

Restriction by hardware caused the very low projection number at a single phase for 4-dimensional cone beam (4D-CBCT) CT imaging, and reconstruction using conventional reconstruction algorithms is thus constrained by serious streak artifacts and noises. To address this problem, we propose an approach to reconstructing 4D-CBCT images with multi-phase projections based on the assumption that the image at one phase can be viewed as the motion-compensated image at another phase. Specifically, we formulated a cost function using multi-phase projections to construct the fidelity term and the TV regularization method. For fidelity term construction, the projection data of the current phase and those at other phases were jointly used by reformulating the imaging model. The Gradient-Projection-Barzilai-Line search (GPBL) method was used to optimize the complex cost function. Physical phantom and patient data results showed that the proposed approach could effectively reduce the noise and artifacts, and the introduction of additional temporal correlation did not introduce new artifacts or motion blur.

Effects of eye acupuncture therapy on neurological function and brain-derived neurotrophic factor expression in a rat model of cerebral ischemia/reperfusion injury / 中国组织工程研究

BACKGROUND: Eye acupuncture therapy is a technique used to adjust qi-blood circulation, relax muscles and tendons, and activate col aterals by acupuncture at the acupoints around the eye bal s and in the orbital border. This therapy has been widely used in the clinic because it exhibits remarkable therapeutic effects on many ischemic cerebrovascular diseases. However, the precise mechanism behind this therapy remains poorly understood. Neurotrophic factors are a protein family including neurotrophic factors and brain-derived neurotrophic factors that can regulate neuronal survival, development and functioning. OBJECTIVE: To investigate the effects of eye acupuncture therapy on neurological function and nerve growth factor and brain-derived neurotrophic factor expression in the brain tissue of rat models of cerebral ischemia/reperfusion injury. METHODS: Fifty-four male Sprague-Dawley rats were randomly divided into three groups with 18 rats per group: sham-operated, model and eye acupuncture therapy groups. Rat models of middle cerebral artery occlusion were established by the intraluminal suture method in the model and eye acupuncture therapy groups. Eye acupuncture was performed at the fol owing acupoints liver area, upper-jiao area, lower-jiao area and kidney area located at the internal orbital margin at 2 hours after cerebral ischemia/reperfusion injury. Rat neurological function was evaluated at 3, 7, and 14 days after injury. Nerve growth factor and brain-derived neurotrophic factor expression in the rat brain tissue was detected using immunohistochemical staining method at 1 and 2 weeks after treatment. Cerebral infarct size was determined using TTC staining at 2 weeks after treatment. RESULTS AND CONCLUSION: (1) At 1 and 2 weeks after injury, nerve growth factor and brain-derived neurotrophic factor expression was significantly greater in the eye acupuncture therapy group than in the model group (P < 0.05), but nerve growth factor and brain-derived neurotrophic factor expression in the eye acupuncture therapy group was decreased at 2 weeks after injury compared to that at 1 week after injury. (2) At 7 and 14 days after treatment, neurological function scores in the eye acupuncture therapy group were significantly lowered, and there was significant difference between eye acupuncture therapy and model groups (P < 0.05), but they were significantly higher than those in the sham-operated group (P< 0.05). (3) At 2 weeks after treatment, cerebral infarct size was significantly greater in the eye acupuncture therapy and model groups than in the sham-operated group (P < 0.01), and it was significantly smal er in the eye acupuncture therapy group than in the model group (P < 0.05). (4)These results indicate that eye acupuncture therapy shows neuroprotective effects on ischemic cerebral injury by increasing nerve growth factor and brain-derived neurotrophic factor expression, improving neurological function, and reducing cerebral infarct size.