Magnetic-field induced shape memory hydrogels for deformable actuators.

Magnetic hydrogel actuators exhibit promising applications in the fields of soft robotics, bioactuators, and flexible sensors owing to their inherent advantages such as remote control capability, untethered deformation and motion control, as well as easily manipulable behavior. However, it is still a challenge for magnetic hydrogels to achieve adjustable stiffness and shape fixation under magnetic field actuation deformation. Herein, a simple and effective approach is proposed for the design of magnetic shape memory hydrogels to accomplish this objective. The magnetic shape memory hydrogels, consisting of methacrylamide, methacrylic acid, polyvinyl alcohol and Fe3O4 magnetic particles, which crosslinked by hydrogen bonds, are facilely prepared via one-pot polymerization. The dynamic nature of noncovalent bonds offers the magnetic hydrogels with excellent mechanical properties, precisely controlled stiffness, and effective shape fixation. The presence of Fe3O4 particles renders the hydrogels soft when subjected to an alternating current field, facilitating their deformation under the influence of an actuation magnetic field. After the elimination of the alternating current magnetic field, the hydrogels stiffen and attain a fixed actuated shape in the absence of any external magnetic field. Moreover, this remarkable magnetic shape memory hydrogel is effectively employed as an underwater soft gripper for lifting heavy objects. This work provides a novel strategy for fabricating magnetic hydrogels with non-contact reversible actuation deformation, tunable stiffness and shape locking.

Postmortem Diffusion of Aconitum Alkaloids and Their Metabolites in Rabbits.

OBJECTIVES: To explore the postmortem diffusion rule of Aconitum alkaloids and their metabolites in poisoned rabbits, and to provide a reference for identifying the antemortem poisoning or postmortem poisoning of Aconitum alkaloids. METHODS: Twenty-four rabbits were sacrificed by tracheal clamps. After 1 hour, the rabbits were administered with aconitine LD50 in decocting aconite root powder by intragastric administration. Then, they were placed supine and stored at 25 ℃. The biological samples from 3 randomly selected rabbits were collected including heart blood, peripheral blood, urine, heart, liver, spleen, lung and kidney tissues at 0 h, 4 h, 8 h, 12 h, 24 h, 48 h, 72 h and 96 h after intragastric administration, respectively. Aconitum alkaloids and their metabolites in the biological samples were analyzed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). RESULTS: At 4 h after intragastric administration, Aconitum alkaloids and their metabolites could be detected in heart blood, peripheral blood and major organs, and the contents of them changed dynamically with the preservation time. The contents of Aconitum alkaloids and their metabolites were higher in the spleen, liver and lung, especially in the spleen which was closer to the stomach. The average mass fraction of benzoylmesaconine metabolized in rabbit spleen was the highest at 48 h after intragastric administration. In contrast, the contents of Aconitum alkaloids and their metabolites in kidney were all lower. Aconitum alkaloids and their metabolites were not detected in urine. CONCLUSIONS: Aconitum alkaloids and their metabolites have postmortem diffusion in poisoned rabbits, diffusing from high-content organs (stomach) to other major organs and tissues as well as the heart blood. The main mechanism is the dispersion along the concentration gradient, while urine is not affected by postmortem diffusion, which can be used as the basis for the identification of antemortem and postmortem Aconitum alkaloids poisoning.

A novel method for determining postmortem interval based on the metabolomics of multiple organs combined with ensemble learning techniques.

Determining postmortem interval (PMI) is one of the most challenging and essential endeavors in forensic science. Developments in PMI estimation can take advantage of machine learning techniques. Currently, applying an algorithm to obtain information on multiple organs and conducting joint analysis to accurately estimate PMI are still in the early stages. This study aimed to establish a multi-organ stacking model that estimates PMI by analyzing differential compounds of four organs in rats. In a total of 140 rats, skeletal muscle, liver, lung, and kidney tissue samples were collected at each time point after death. Ultra-performance liquid chromatography coupled with high-resolution mass spectrometry was used to determine the compound profiles of the samples. The original data were preprocessed using multivariate statistical analysis to determine discriminant compounds. In addition, three interrelated and increasingly complex patterns (single organ optimal model, single organ stacking model, multi-organ stacking model) were established to estimate PMI. The accuracy and generalized area under the receiver operating characteristic curve of the multi-organ stacking model were the highest at 93% and 0.96, respectively. Only 1 of the 14 external validation samples was misclassified by the multi-organ stacking model. The results demonstrate that the application of the multi-organ combination to the stacking algorithm is a potential forensic tool for the accurate estimation of PMI.

Pazopanib alleviates neuroinflammation and protects dopaminergic neurons in LPS-stimulated mouse model by inhibiting MEK4-JNK-AP-1 pathway.

Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by the loss of dopaminergic (DA) neurons and the accumulation of Lewy bodies (LB) in the substantia nigra (SN). Evidence shows that microglia-mediated neuroinflammation plays a key role in PD pathogenesis. Using TNF-α as an indicator for microglial activation, we established a cellular model to screen compounds that could inhibit neuroinflammation. From 2471 compounds in a small molecular compound library composed of FDA-approved drugs, we found 77 candidates with a significant anti-inflammatory effect. In this study, we further characterized pazopanib, a pan-VEGF receptor tyrosine kinase inhibitor (that was approved by the FDA for the treatment of advanced renal cell carcinoma and advanced soft tissue sarcoma). We showed that pretreatment with pazopanib (1, 5, 10 µM) dose-dependently suppressed LPS-induced BV2 cell activation evidenced by inhibiting the transcription of proinflammatory factors iNOS, COX2, Il-1ß, and Il-6 through the MEK4-JNK-AP-1 pathway. The conditioned medium from LPS-treated microglia caused mouse DA neuronal MES23.5 cell damage, which was greatly attenuated by pretreatment of the microglia with pazopanib. We established an LPS-stimulated mouse model by stereotactic injection of LPS into mouse substantia nigra. Administration of pazopanib (10 mg·kg-1·d-1, i.p., for 10 days) exerted significant anti-inflammatory and neuronal protective effects, and improved motor abilities impaired by LPS in the mice. Together, we discover a promising candidate compound for anti-neuroinflammation and provide a potential repositioning of pazopanib in the treatment of PD.

Assessing the role of SH3RF1 and SH3RF2 polymorphisms in susceptibility to tuberculosis: A case-control study in the Han Chinese population.

BACKGROUND: Tuberculosis (TB) remains a major public health problem. SH3RF1 and SH3RF2 are candidate genes with multiple single-nucleotide polymorphisms (SNPs) that have the potential to participate in Mycobacterium infection via activation of the JNK signaling pathway. In this case-control study, we aimed to investigate the association of five SH3RF1 and SH3RF2 SNPs with susceptibility to TB in the Western Chinese population. METHODS: A total of 900 TB patients and 1534 healthy control subjects were enrolled in our study. All samples used were obtained from the Bio-Bank of resources of Tuberculosis Research in the Department of Laboratory Medicine, West China Hospital, Sichuan University, China. SNP genotyping was conducted using a commercial custom-by-design 2 × 48-Plex SNPscan Kit. RESULTS: The rs758037 variant of the SH3RF2 gene was found to be associated with decreased TB risk based on allelic effects (p = 0.00001, OR = 0.731, 95% CI = 0.641-0.833) and three genetic models (padd = 0.00001, pdom = 0.0003, prec = 0.0007) after the data were controlled for age and gender and underwent Bonferroni correction. The rs4913057 variant of the SH3RF2 gene was found to be associated with increased TB risk in a dominant model (p = 0.021, OR: 1.260, 95% CI: 1.065-1.490). No significant association was observed between other SNPs and TB risk. CONCLUSION: These findings indicate that polymorphisms in the SH3RF2 gene are involved in susceptibility to TB in the Western Chinese population.

Engrafted primary type-2 astrocytes improve the recovery of the nigrostriatal pathway in a rat model of Parkinson's disease.

Parkinson's disease (PD) is a disorder characterized by a progressive loss of the dopaminergic neurons in the substantia nigra and a depletion of the neurotransmitter dopamine in the striatum. Our published results indicate that fasciculation and elongation protein zeta-1 (FEZ1) plays a role in the astrocyte-mediated protection of dopamine neurons and regulation of the neuronal microenvironment during the progression of PD. In this study, we examined the effects of engrafted type-2 astrocytes (T2As) with high expression of FEZ1 on the improvement of the symptoms and functional reconstruction of PD rats. T2As were stereotactically transplanted into the striatum of rats with PD induced by 6-hydroxydopamine (6-OHDA). An examination of apomorphine (APO)-induced rotations was performed to evaluate dopamine neuron damage and motor functions. Remarkably, the grafted cells survived in the lesion environment for six weeks or longer after implantation. In addition, the transplantation of T2As decrease the average velocity and the duration time of the APO-induced rotations, and increase the actuation time, as measured in the rotation behavioural tests. In the substantia nigra, the transplantation of T2As reduced the PD-induced GFAP, TH and FEZ1 downregulation. The grafted cells exclusively migrated to other regions near the injection site in the striatum and differentiated into GFAP+ astrocytes or TH+ neurons. Furthermore, by detecting monoamine neurotransmitters through high-performance liquid chromatography, we found that the nigrostriatal pathway had been repaired to some extent. Taken together, these results suggest that engrafted T2As with high expression of FEZ1 improved the symptoms and functional reconstruction of PD rats, providing a theoretical basis for FEZ1 as a potential target and engraftment of T2As as a therapeutic strategy in the treatment of PD.

Personal Interest Attention Graph Neural Networks for Session-Based Recommendation.

Session-based recommendations aim to predict a user's next click based on the user's current and historical sessions, which can be applied to shopping websites and APPs. Existing session-based recommendation methods cannot accurately capture the complex transitions between items. In addition, some approaches compress sessions into a fixed representation vector without taking into account the user's interest preferences at the current moment, thus limiting the accuracy of recommendations. Considering the diversity of items and users' interests, a personalized interest attention graph neural network (PIA-GNN) is proposed for session-based recommendation. This approach utilizes personalized graph convolutional networks (PGNN) to capture complex transitions between items, invoking an interest-aware mechanism to activate users' interest in different items adaptively. In addition, a self-attention layer is used to capture long-term dependencies between items when capturing users' long-term preferences. In this paper, the cross-entropy loss is used as the objective function to train our model. We conduct rich experiments on two real datasets, and the results show that PIA-GNN outperforms existing personalized session-aware recommendation methods.

A Novel Adaptive Feature Fusion Strategy for Image Retrieval.

In the era of big data, it is challenging to efficiently retrieve the required images from the vast amount of data. Therefore, a content-based image retrieval system is an important research direction to address this problem. Furthermore, a multi-feature-based image retrieval system can compensate for the shortage of a single feature to a certain extent, which is essential for improving retrieval system performance. Feature selection and feature fusion strategies are critical in the study of multi-feature fusion image retrieval. This paper proposes a multi-feature fusion image retrieval strategy with adaptive features based on information entropy theory. Firstly, we extract the image features, construct the distance function to calculate the similarity using the information entropy proposed in this paper, and obtain the initial retrieval results. Then, we obtain the precision of single feature retrieval based on the correlation feedback as the retrieval trust and use the retrieval trust to select the effective features automatically. After that, we initialize the weights of selected features using the average weights, construct the probability transfer matrix, and use the PageRank algorithm to update the initialized feature weights to obtain the final weights. Finally, we calculate the comprehensive similarity based on the final weights and output the detection results. This has two advantages: (1) the proposed strategy uses multiple features for image retrieval, which has better performance and more substantial generalization than the retrieval strategy based on a single feature; (2) compared with the fixed-feature retrieval strategy, our method selects the best features for fusion in each query, which takes full advantages of each feature. The experimental results show that our proposed method outperforms other methods. In the datasets of Corel1k, UC Merced Land-Use, and RSSCN7, the top10 retrieval precision is 99.55%, 88.02%, and 88.28%, respectively. In the Holidays dataset, the mean average precision (mAP) was 92.46%.

Estimating Postmortem Interval Using Intestinal Microbiota Diversity Based on 16S rRNA High-throughput Sequencing Technology. / 基于16S rRNAé«˜é€šé‡æµ‹åºæŠ€æœ¯çš„è‚ é“èŒç¾¤å¤šæ ·æ€§æŽ¨æ–­æ­»äº¡æ—¶é—´.

OBJECTIVES: To explore the correlation between intestinal microbiota and postmortem interval(PMI) in rats by using 16S rRNA high-throughput sequencing technology. METHODS: Rats were killed by anesthesia and placed at 16 ℃, and DNA was extracted in caecum at 14 time points of 0, 1, 2, 3, 5, 7, 9, 12, 15, 18, 21, 24, 27 and 30 d after death. The 16S rRNA high-throughput sequencing technology was used to detect intestinal microbiota in rat cecal contents, and the results were used to analyze the rat intestinal microbiota diversity and differences. RESULTS: The total number of intestinal microbial communities did not change significantly within 30 days after death, but the diversity showed an upward trend. A total of 119 bacterial communities were significantly changed at 13 time points after death. The models for PMI estimation were established by using partial least squares (PLS) regression at all time points, before 9 days and after 12 days, reaching an R2 of 0.795, 0.767 and 0.445, respectively; and the root mean square errors (RMSEs) were 6.57, 1.96 and 5.37 d, respectively. CONCLUSIONS: Using 16S rRNA high-throughput sequencing technology, the composition and structure of intestinal microbiota changed significantly within 30 d after death. In addition, the established PLS regression model suggested that the PMI was highly correlated with intestinal microbiota composition, showing a certain time series change.

Long Noncoding RNA and Predictive Model To Improve Diagnosis of Clinically Diagnosed Pulmonary Tuberculosis.

Clinically diagnosed pulmonary tuberculosis (PTB) patients lack microbiological evidence of Mycobacterium tuberculosis, and misdiagnosis or delayed diagnosis often occurs as a consequence. We investigated the potential of long noncoding RNAs (lncRNAs) and corresponding predictive models to diagnose these patients. We enrolled 1,764 subjects, including clinically diagnosed PTB patients, microbiologically confirmed PTB cases, non-TB disease controls, and healthy controls, in three cohorts (screening, selection, and validation). Candidate lncRNAs differentially expressed in blood samples of the PTB and healthy control groups were identified by microarray and reverse transcription-quantitative PCR (qRT-PCR) in the screening cohort. Logistic regression models were developed using lncRNAs and/or electronic health records (EHRs) from clinically diagnosed PTB patients and non-TB disease controls in the selection cohort. These models were evaluated by area under the concentration-time curve (AUC) and decision curve analyses, and the optimal model was presented as a Web-based nomogram, which was evaluated in the validation cohort. Three differentially expressed lncRNAs (ENST00000497872, n333737, and n335265) were identified. The optimal model (i.e., nomogram) incorporated these three lncRNAs and six EHRs (age, hemoglobin, weight loss, low-grade fever, calcification detected by computed tomography [CT calcification], and interferon gamma release assay for tuberculosis [TB-IGRA]). The nomogram showed an AUC of 0.89, a sensitivity of 0.86, and a specificity of 0.82 in differentiating clinically diagnosed PTB cases from non-TB disease controls of the validation cohort, which demonstrated better discrimination and clinical net benefit than the EHR model. The nomogram also had a discriminative power (AUC, 0.90; sensitivity, 0.85; specificity, 0.81) in identifying microbiologically confirmed PTB patients. lncRNAs and the user-friendly nomogram could facilitate the early identification of PTB cases among suspected patients with negative M. tuberculosis microbiological evidence.

Robotic Perineal Radical Prostatectomy: Initial Experience with the da Vinci Si Robotic System.

PURPOSE: To investigate the feasibility and surgical technique of robotic perineal radical prostatectomy (RPRP). MATERIALS AND METHODS: We retrospectively analyzed 6 consecutive patients diagnosed with prostate cancer from December 2018 to May 2019 who underwent RPRP at our center. Perioperative outcomes were recorded for safety and feasibility analysis. RESULTS: Six patients successfully underwent RPRP with no conversion to open procedures. Operative time was 140 (interquartile range [IQR] 123.75-148.75) min, console time was 70 (IQR 62.5-70) min, with an estimated blood loss of 125 (IQR 100-187.5) mL. Patients were discharged 2 days postoperatively (IQR range 1-3) with pelvic drainages removed. The Foley catheter was removed 2 weeks after surgery. Postoperative pathology revealed 5 patients with locally advanced disease (apical margin-positive prostate cancer [pT3a]bNx). Two patients had a positive surgical margin (33.3%). No complications of Clavien grade 3 and above were recorded; 1 patient had a delay in wound-healing of 1 week. Postoperative continence was achieved for 2 patients immediately after Foley catheter removal, 2 recovered 1-month postoperatively, and 1 recovered within 3 months, and 1 still had mild incontinence at the latest follow-up 1-month postoperatively. CONCLUSION: RPRP is a safe and feasible alternative for the transperitoneal route in selected patients. Further investigation is required to assess its oncological and quality-of-life results.

Interlaboratory Comparison of Hydrogen-Deuterium Exchange Mass Spectrometry Measurements of the Fab Fragment of NISTmAb.

Hydrogen-deuterium exchange mass spectrometry (HDX-MS) is an established, powerful tool for investigating protein-ligand interactions, protein folding, and protein dynamics. However, HDX-MS is still an emergent tool for quality control of biopharmaceuticals and for establishing dynamic similarity between a biosimilar and an innovator therapeutic. Because industry will conduct quality control and similarity measurements over a product lifetime and in multiple locations, an understanding of HDX-MS reproducibility is critical. To determine the reproducibility of continuous-labeling, bottom-up HDX-MS measurements, the present interlaboratory comparison project evaluated deuterium uptake data from the Fab fragment of NISTmAb reference material (PDB: 5K8A ) from 15 laboratories. Laboratories reported ∼89 800 centroid measurements for 430 proteolytic peptide sequences of the Fab fragment (∼78 900 centroids), giving ∼100% coverage, and ∼10 900 centroid measurements for 77 peptide sequences of the Fc fragment. Nearly half of peptide sequences are unique to the reporting laboratory, and only two sequences are reported by all laboratories. The majority of the laboratories (87%) exhibited centroid mass laboratory repeatability precisions of ⟨ sLab⟩ ≤ (0.15 ± 0.01) Da (1σx̅). All laboratories achieved ⟨sLab⟩ ≤ 0.4 Da. For immersions of protein at THDX = (3.6 to 25) °C and for D2O exchange times of tHDX = (30 s to 4 h) the reproducibility of back-exchange corrected, deuterium uptake measurements for the 15 laboratories is σreproducibility15 Laboratories( tHDX) = (9.0 ± 0.9) % (1σ). A nine laboratory cohort that immersed samples at THDX = 25 °C exhibited reproducibility of σreproducibility25C cohort( tHDX) = (6.5 ± 0.6) % for back-exchange corrected, deuterium uptake measurements.

Interleukin-21 receptor gene polymorphism is associated with hepatitis B virus-related hepatocellular carcinoma in Chinese patients.

BACKGROUND: We investigated the relationship between hepatitis B virus (HBV)-related pathogenesis and single nucleotide polymorphisms (SNPs) in interleukin-21 (IL-21)-JAK-STAT signaling pathway genes. METHODS: We used the high-resolution melting (HRM) method to genotype five SNPs (IL-21 rs2221903, IL-21 rs4833837, IL-21 receptor (IL-21R) rs2285452, JAK3 rs3008, and STAT3 rs1053023) in 546 HBV-infected patients and 353 healthy Chinese subjects. The HBV-infected patients were further divided into subgroups based on the HBV-related pathologies: chronic hepatitis B (CHB), HBV-related liver cirrhosis (LC), and HBV-related hepatocellular carcinoma (HCC). RESULTS: There were no significant differences in the genotype and allele distributions of the five SNPs between the HBV-infected patients and healthy subjects. The genotype and allele frequencies were similar in the two groups for IL-21 rs2221903 (A>G, P = 0.83 and 0.67), rs4833837 (A>G, P = 0.80 and 0.49), IL-21R rs2285452 (G>A, P = 0.25 and 0.68), STAT3 rs1053023 (A>G, P = 1.00 and 0.96), and JAK3 rs3008 (C>T, P = 0.32 and 0.54). However, patients with the IL-21R rs2285452 AA genotype were more susceptible to HBV-related HCC than those with the IL-21R rs2285452 GA/GG genotype (P = 0.03, OR = 3.27, 95% CI = 1.16-9.20). The serological marker model of "HBsAg+, HBeAg+, HBcAb+" was predominant among patients with HBV infection. However, there was no association between the genotype's distribution of the five SNPs and the serological marker models (P > 0.05). CONCLUSIONS: These findings demonstrate that the IL-21R rs2285452 AA genotype increases the risk of HBV-related HCC in Chinese patients.

Development and validation of an advanced fragment analysis-based assay for the detection of 22 pathogens in the cerebrospinal fluid of patients with meningitis and encephalitis.

BACKGROUND: Meningitis and encephalitis (ME) are central nervous system (CNS) infections mainly caused by bacteria, mycobacteria, fungi, viruses, and parasites that result in high morbidity and mortality. The early, accurate diagnosis of pathogens in the cerebrospinal fluid (CSF) and timely medication are associated with better prognosis. Conventional methods, such as culture, microscopic examination, serological detection, CSF routine analysis, and radiological findings, either are time-consuming or lack sensitivity and specificity. METHODS: To address these clinical needs, we developed an advanced fragment analysis (AFA)-based assay for the multiplex detection of 22 common ME pathogens, including eight viruses, 11 bacteria, and three fungi. The detection sensitivity of each target was evaluated with a recombinant plasmid. The limits of detection of the 22 pathogens ranged from 15 to 120 copies/reaction. We performed a retrospective study to analyze the pathogens from the CSF specimens of 170 clinically diagnosed ME patients using an AFA-based assay and compared the results with culture (bacteria and fungi), microscopic examination (fungi), polymerase chain reaction (PCR) (Mycobacterium tuberculosis), and Sanger sequencing (virus) results. RESULTS: The sensitivity of the AFA assay was 100% for 10 analytes. For Cryptococcus neoformans, the sensitivity was 63.6%. The overall specificity was 98.2%. The turnaround time was reduced to 4-6 hours from the 3-7 days required using conventional methods. CONCLUSIONS: In conclusion, the AFA-based assay provides a rapid, sensitive, and accurate method for pathogen detection from CSF samples.

[Retraction Note: Association of Gene Polymorphisms in Wnt Signal Pathway with Tuberculosis in Chinese Tibetan Population.2016,47(6):920-925.]

This corrects the article DOI: 10.13464/j.scuxbyxb.2016.06.021.

Influence of genetic polymorphisms of IL23R, STAT3, IL12B, and STAT4 on the risk of aplastic anemia and the effect of immunosuppressive therapy.

Studies have suggested that IL-23/STAT3 and IL-12/STAT4 signaling pathways associate with aplastic anemia (AA) occurrence. Polymorphisms in pathway-related genes may contribute to AA risk. In the current study, we investigated the association between polymorphisms in genes of IL23R, STAT3, IL12B, and STAT4 and occurrence, severity, and immunosuppressive outcome of AA in the Han population in southwest China. In the current 164 AA cases and 211 controls study, we found T allele and TT genotype of rs7574865 were more frequent in the cases than that in the controls. In the additive model, individual carrying rs7574865 T allele demonstrated a 37% (OR (95% CI) = 1.37 (1.02-1.85), Pper = 0.036) increased AA risk. In the recessive model, carrier with rs7574865 TT genotype showed a 2.08-fold increased AA risk (OR (95% CI) = 2.08 (1.14-3.70), Pper = 0.017). Additionally, we showed that G allele and GG genotype of rs11209032 were more frequent in the 88 non-severe AA cases than that in the 76 severe AA ones. Our study also found G allele and GG genotype of rs11209032, and GG-genotype of rs744166 associated with the immunosuppressive therapy outcome in AA patients. Current study results support that functional STAT4 (rs7574865), IL23R (rs11209032), and STAT3 (rs744166) variants may associate with occurrence, severity, and immunosuppressive outcome of AA in the Han population in southwest China.

Genetic polymorphisms of 21 autosomal STR loci in Chinese Uygur ethnic population.

Genetic polymorphisms of 21 short tandem repeat (STR) loci were studied in 576 unrelated Uygur individuals living in Urumqi using Goldeneye™ DNA ID 22NC system. Population data of all loci, except one locus (D1S1656), had no significant deviation from Hardy-Weinberg equilibrium. A high degree of genetic polymorphisms was showed by all STR loci in Urumchi Uygur population. The combined power of discrimination (CPD) was 0.999999999999999999999999985256 and the combined power of exclusion (CPE) was 0.999999997207836. In addition, we performed comparisons between the data from Uygur population with previously published data obtained from other populations.

An Adaptive Weight Method for Image Retrieval Based Multi-Feature Fusion.

With the rapid development of information storage technology and the spread of the Internet, large capacity image databases that contain different contents in the images are generated. It becomes imperative to establish an automatic and efficient image retrieval system. This paper proposes a novel adaptive weighting method based on entropy theory and relevance feedback. Firstly, we obtain single feature trust by relevance feedback (supervised) or entropy (unsupervised). Then, we construct a transfer matrix based on trust. Finally, based on the transfer matrix, we get the weight of single feature through several iterations. It has three outstanding advantages: (1) The retrieval system combines the performance of multiple features and has better retrieval accuracy and generalization ability than single feature retrieval system; (2) In each query, the weight of a single feature is updated dynamically with the query image, which makes the retrieval system make full use of the performance of several single features; (3) The method can be applied in two cases: supervised and unsupervised. The experimental results show that our method significantly outperforms the previous approaches. The top 20 retrieval accuracy is 97.09%, 92.85%, and 94.42% on the dataset of Wang, UC Merced Land Use, and RSSCN7, respectively. The Mean Average Precision is 88.45% on the dataset of Holidays.

[Methylation Analysis and Validation of Whole Genome DNA in Active Tuberculosis].

OBJECTIVE: To screen and identify the gene of DNA methylation in patients with active tuberculosis. METHODS: ① This study enrolled 9 cases of active tuberculosis patients (including 3 newly diagnosed tuberculosis patients and 6 cases of retreatment of active tuberculosis patients), 3 cases of latent tuberculosis patients and 3 cases of healthy controls. Genome DNA was extracted from Peripheral Blood Mononuclear Cell and following bisulfite conversion treatment. After hybridization with the Illumina HD 450K Infinium Mehtylation BeadChip, the results were compared between patients group and control group, GO and Pathway analysis were performed to evaluate the function of differentially expressed genes; ② We further enrolled 60 cases of active tuberculosis patients and 60 cases of health controls (their age and gender were matched). By using pyrosequencing method to detect the methylation levels of candidate genes (TLR1, TLR2, TLR4) screened by gene chip. RESULTS: ① Compared with healthy controls, we found that most of them were showed demethylation status. GO and Pathway analysis showed that the functions of the differentially methylated regions related genes were mainly enriched in the biological processes of the regulation of leukocyte apoptosis, cytokine regulation and inflammatory response which were closely related to tuberculosis. ②There were 10 CpG sites involved in the verified tuberculosis related genes (TLR1, TLR2, TLR4), the CpG sites of TLR1 gene showed the hypermethylation status (P<0.001), the CpG sites of TLR4 gene showed demethylation status (P=0.012). CONCLUSION: The present study demonstrated that in the course of MTB infection, the methylation status of genomic DNA was altered, and most of the Differentially Methylated Regions (DMRs) were showed status of demethylation. TLR1 gene and TLR4 gene may play an important role in the occurrence and development of tuberculosis.

[Etiology, Prognosis and Risk Factors of 181 Adult Community-acquired Acute Bacterial Meningitis].

OBJECTIVE: To understand the etiology, clinical prognosis and risk factors of adult community-acquired acute bacterial meningitis (ABM) and provide the evidence for clinical diagnosis and treatment. METHODS: We performed a retrospective study of 181 clinically diagnosed hospitalized patients with community-acquired adult ABM from Jan.2010 to Jan.2018. The patients were categorized as non-elderly (16≤age<65 years old, n=156 ) and elderly (age≥65 years old, n=25) group. The etiology, clinical features, prognosis and risk factors of the two groups were compared. RESULTS: Sixty-four of 181 patients (35.4%) had pathogens detected. The most common pathogens were Streptococcus pneumoniae (17.9%), Listeria monocytogenes (13.4%) and Klebsiella pneumoniae (10.5%). The mortality of the elderly group was higher than that of the non-elderly group (P<0.05). Univariate analysis showed that there was a significant difference between the elderly group and the non-elderly group in the incidence of hypertension, hypokalemia, pulmonary infection, ear-nose-throat ( ENT) infection, cerebrospinal fluid (CSF) protein concentration, head CT abnormalities and mortality. Logistic regression analysis showed that pulmonary infection and temperature ≥38.5 ℃ were independent risk factors for poor prognosis in the non-elderly group. CSF pressure ≥200 mmH2O was a independent risk factors for poor prognosis in the elderly group. CONCLUSION: The pathogens that cause acute bacterial meningitis in adult community are mainly Streptococcus pneumoniae, Listeria monocytogenes and Klebsiella pneumoniae.Pulmonary infection and temperature ≥38.5 ℃ are independent risk factors of poor prognosis in the non-elderly patients, as CSF pressure ≥200 mmH2O a independent risk factor in the elderly patients.