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1.
Quant Imaging Med Surg ; 12(8): 4259-4271, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35919046

RESUMO

Background: Because osteoporotic vertebral fracture (OVF) on chest radiographs is commonly missed in radiological reports, we aimed to develop a software program which offers automated detection of compressive vertebral fracture (CVF) on lateral chest radiographs, and which emphasizes CVF detection specificity with a low false positivity rate. Methods: For model training, we retrieved 3,991 spine radiograph cases and 1,979 chest radiograph cases from 16 sources, with among them in total 1,404 cases had OVF. For model testing, we retrieved 542 chest radiograph cases and 162 spine radiograph cases from four independent clinics, with among them 215 cases had OVF. All cases were female subjects, and except for 31 training data cases which were spine trauma cases, all the remaining cases were post-menopausal women. Image data included DICOM (Digital Imaging and Communications in Medicine) format, hard film scanned PNG (Portable Network Graphics) format, DICOM exported PNG format, and PACS (Picture Archiving and Communication System) downloaded resolution reduced DICOM format. OVF classification included: minimal and mild grades with <20% or ≥20-25% vertebral height loss respectively, moderate grade with ≥25-40% vertebral height loss, severe grade with ≥40%-2/3 vertebral height loss, and collapsed grade with ≥2/3 vertebral height loss. The CVF detection base model was mainly composed of convolution layers that include convolution kernels of different sizes, pooling layers, up-sampling layers, feature merging layers, and residual modules. When the model loss function could not be further decreased with additional training, the model was considered to be optimal and termed 'base-model 1.0'. A user-friendly interface was also developed, with the synthesized software termed 'Ofeye 1.0'. Results: Counting cases and with minimal and mild OVFs included, base-model 1.0 demonstrated a specificity of 97.1%, a sensitivity of 86%, and an accuracy of 93.9% for the 704 testing cases. In total, 33 OVFs in 30 cases had a false negative reading, which constituted a false negative rate of 14.0% (30/215) by counting all OVF cases. Eighteen OVFs in 15 cases had OVFs of ≥ moderate grades missed, which constituted a false negative rate of 7.0% (15/215, i.e., sensitivity 93%) if only counting cases with ≥ moderate grade OVFs missed. False positive reading was recorded in 13 vertebrae in 13 cases (one vertebra in each case), which constituted a false positivity rate of 2.7% (13/489). These vertebrae with false positivity labeling could be readily differentiated from a true OVF by a human reader. The software Ofeye 1.0 allows 'batch processing', for example, 100 radiographs can be processed in a single operation. This software can be integrated into hospital PACS, or installed in a standalone personal computer. Conclusions: A user-friendly software program was developed for CVF detection on elderly women's lateral chest radiographs. It has an overall low false positivity rate, and for moderate and severe CVFs an acceptably low false negativity rate. The integration of this software into radiological practice is expected to improve osteoporosis management for elderly women.

2.
Proc Natl Acad Sci U S A ; 119(32): e2203883119, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914168

RESUMO

L-type CaV1.3 calcium channels are expressed on the dendrites and soma of neurons, and there is a paucity of information about its role in hippocampal plasticity. Here, by genetic targeting to ablate CaV1.3 RNA editing, we demonstrate that unedited CaV1.3ΔECS mice exhibited improved learning and enhanced long-term memory, supporting a functional role of RNA editing in behavior. Significantly, the editing paradox that functional recoding of CaV1.3 RNA editing sites slows Ca2+-dependent inactivation to increase Ca2+ influx but reduces channel open probability to decrease Ca2+ influx was resolved. Mechanistically, using hippocampal slice recordings, we provide evidence that unedited CaV1.3 channels permitted larger Ca2+ influx into the hippocampal pyramidal neurons to bolster neuronal excitability, synaptic transmission, late long-term potentiation, and increased dendritic arborization. Of note, RNA editing of the CaV1.3 IQ-domain was found to be evolutionarily conserved in mammals, which lends support to the importance of the functional recoding of the CaV1.3 channel in brain function.


Assuntos
Canais de Cálcio Tipo L , Edição de RNA , Animais , Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Hipocampo/metabolismo , Mamíferos/metabolismo , Camundongos , Plasticidade Neuronal/genética , Neurônios/metabolismo , Células Piramidais/metabolismo
3.
Acta Biomater ; 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35917908

RESUMO

Zinc (Zn) alloys are a promising biodegradable material for vascular stent applications. This study aimed to fabricate biodegradable Zn-2.0Cu-0.5Mn alloy micro-tubes and vascular stents with high dimensional accuracy and suitable mechanical properties, and to investigate their microstructure, texture, mechanical properties and corrosion behavior. The micro-tubes and vascular stents were successfully fabricated by a combined process of extrusion, drawing, laser cutting and electrochemical polishing. The microstructures of as-extruded and as-drawn micro-tubes consisted of Zn matrix with near-equiaxed grains (average grain size: ∼2 µm) and second phases of ε (CuZn4) and MnZn13 with different sizes. The texture evolved from basal planes approximately paralleling to deformation direction for as-extruded micro-tube to approximately perpendicular to deformation direction for as-drawn micro-tube, because predominant deformation mechanisms changed from basal dislocation slip during tube extrusion to prismatic dislocation, pyramidal dislocations, and {101¯2} twins during tube drawing. As-drawn micro-tube exhibited suitable mechanical properties with an ultimate tensile strength of about 298 MPa and elongation of about 26% as a stent material. Moreover, the processed stent with a thickness of about 125 µm possessed sufficient radial strength of about 150 kPa and good balloon expandability. In addition, as-drawn tube exhibited an in vitro corrosion rate of about 158 µm/year with a basically uniform corrosion morphology. These results indicated that biodegradable Zn-2.0Cu-0.5Mn alloy is a promising vascular stent material candidate, and the procedure for processing the micro-tube and stent is practical and effective. STATEMENT OF SIGNIFICANCE: Fabrication of micro-tubes followed by laser cutting and polishing is a common way to prepare metallic vascular stents. However, it is quite challenging to fabricate Zn-based stents using this standard method, and there is a lack of studies reporting processing details in the past. Biodegradable Zn-2.0Cu-0.5Mn alloy micro-tubes and vascular stents with high dimensional accuracy and suitable mechanical properties were successfully fabricated by a combined process in this study. As-drawn micro-tube exhibited an ultimate tensile strength of about 298 MPa and elongation of about 26%. The stent possessed sufficient radial strength of about 150 kPa and good balloon expandability. We demonstrated a practical method to fabricate biodegradable Zn-based micro-tubes and stents with high dimensional accuracy and mechanical properties.

4.
Org Lett ; 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35920748

RESUMO

A visible-light-induced four-component reaction of vinylcyclopropanes, N-(acyloxy)phthalimide esters, N,N-dimethylformamide (DMF), and H2O through an oxidative ring opening of cyclopropane is presented. This procedure provides a new and effective way to construct formate esters. DMF is employed as both a solvent and the source of CHO. This difunctionalization of vinylcyclopropanes shows good functional group tolerance under room temperature. A radical pathway is involved, and carbonyl oxygen of ester originated from water in this transformation.

5.
World Neurosurg ; 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35803570

RESUMO

OBJECTIVE: To identify the significant predictors of overall survival for patients living with diffused large B-cell lymphoma (DLBCL) in the central nervous system and establish a novel decision tree model to help predict survival status at several time points. METHODS: Patients diagnosed with DLBCL were identified from the SEER database and randomly divided into training and test samples (6:4). Dichotomous decision trees were developed for survival status at 3, 12, 24, and 60 months. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy rate, and area under the receiver operating characteristic curve were calculated to evaluate the model performance. RESULTS: A total of 2998 patients were included, with 1799 and 1199 patients divided into the training and testing groups. Decision trees for 3, 12, 24, and 60 months survival status were generated. Chemotherapy and patient's age were of the primary importance for prognosis in the novel models. Favorable consistency between the predicted and actual survival status was presented. The accuracy rates were 0.79, 0.71, 0.68, and 0.86 for training sample at 3, 12, 24, and 60 months, respectively, and 0.75, 0.69, 0.58, and 0.84 for test sample at 3, 12, 24, and 60 months, respectively. The area under the receiver operating characteristic curve values ranged between 0.645 and 0.721 for the training sample and between 0.607 and 0.712 for the test sample. CONCLUSIONS: Novel decision tree models were established for predicting the 3, 12, 24, and 60 months survival status of patients with DLBCL. The newly developed models were verified using training and test samples, showing favorable accuracy and predictive value on overall survival.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35849674

RESUMO

Most existing methods adopt the quadrilateral or rotated rectangle representation to detect multi-oriented objects. Yet, the same oriented object may correspond to several different representations, due to different vertex ordering, or angular periodicity and edge exchangeability. To ensure the uniqueness of the representation, some engineered rules are usually added. This makes these methods suffer from discontinuity problem, resulting in degraded performance for objects around some orientation. In this paper, we propose to encode the multi-oriented object with double horizontal rectangles (DHRec) to solve the discontinuity problem. Specifically, for an oriented object, we arrange the horizontal and vertical coordinates of its four vertices in left-right and top-down order, respectively. The first (resp second) horizontal box is given by two diagonal points with smallest (resp second) and third (resp largest) coordinates in both horizontal and vertical dimensions. We then regress three factors given by area ratios between different regions, helping to guide the oriented object decoding from the predicted DHRec. Inherited from the uniqueness of horizontal rectangle representation, the proposed method is free of discontinuity issue, and can accurately detect objects of arbitrary orientation. Extensive experimental results show that the proposed method significantly improves the existing baseline representation, and outperforms state-of-the-art methods. The code will be available at: https://github.com/lightbillow/DHRec.

7.
Stem Cell Reports ; 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35868309

RESUMO

Exosomes play a critical role in intracellular communication. The biogenesis and function of exosomes are regulated by multiple biochemical factors. In the present study, we find that mechanical force promotes the biogenesis of exosomes derived from periodontal ligament stem cells (PDLSCs) and alters the exosomal proteome profile to induce osteoclastic differentiation. Mechanistically, mechanical force increases the level of exosomal proteins, especially annexin A3 (ANXA3), which facilitates exosome internalization to activate extracellular signal-regulated kinase (ERK), thus inducing osteoclast differentiation. Moreover, the infusion of exosomes derived from PDLSCs into mice promotes mechanical force-induced tooth movement and increases osteoclasts in the periodontal ligament. Collectively, this study demonstrates that mechanical force treatment promotes the biogenesis of exosomes from PDLSCs and increases exosomal protein ANXA3 to facilitate exosome internalization, which activates ERK phosphorylation, thus inducing osteoclast differentiation. Our findings shed light on new mechanisms for how mechanical force regulates the biology of exosomes and bone metabolism.

8.
J Cancer ; 13(8): 2631-2643, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711827

RESUMO

Lung cancer is the leading cause of cancer-related deaths worldwide. Hypoxia is a crucial microenvironmental factor in lung adenocarcinoma (LUAD). However, the prognostic value based on hypoxia and immune in LUAD remains to be further clarified. The hypoxia-related genes (HRGs) and immune-related genes (IRGs) were downloaded from the public database. The RNA-seq expression and matched complete clinical data for LUAD were retrieved from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. The least absolute shrinkage and selection operator (LASSO) Cox regression analysis was applied to model construction. Hypoxia expression profiles, immune cell infiltration, functional enrichment analysis, Tumor Immune Dysfunction and Exclusion (TIDE) score and the somatic mutation status were analyzed and compared based on the model. Moreover, immunofluorescence (IF) staining in human LUAD cases to explore the expression of hypoxia marker and immune checkpoint. A prognostic model of 9 genes was established, which can divide patients into two subgroups. There were obvious differences in hypoxia and immune characteristics in the two groups, the group with high-risk score value showed significantly high expression of hypoxia genes and programmed death ligand-1 (PD-L1), and maybe more sensitive to immunotherapy. Patients in the high-risk group had shorter overall survival (OS). This model has a good predictive value for the prognosis of LUAD. We constructed a new HRGs and IRGs model for prognostic prediction of LUAD. This model may benefit future immunotherapy for LUAD.

10.
Genomics ; 114(4): 110418, 2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35724730

RESUMO

Circular RNAs (circRNAs) are a new type of regulatory RNAs, which have been identified to play critical role in various tumors. However, the profiles and roles of circRNAs in cervical cancer (CCa) have not been fully understood and need to be further explored. In the present study, we performed circRNA array and mRNA-sequencing (mRNA-Seq) to profile the differentially expressed circRNAs and mRNAs in CCa tissues. A total of 397 differentially expressed circRNAs and 2138 differentially expressed mRNAs were detected, respectively. Subsequently, a circRNA-miRNA-mRNA regulatory network was constructed and indicated that hsa_circ_0026377 was downregulated in CCa. Overexpression of hsa_circ_0026377 inhibited HeLa and SiHa cells proliferation, migration and invasion. Collectively, this study provided new insights into the circRNA profiles in CCa and suggested that hsa_circ_0026377 might play important roles in CCa development.

11.
IEEE Trans Image Process ; 31: 4336-4351, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35727783

RESUMO

Distinguishing between dynamic foreground objects and a mostly static background is a fundamental problem in many computer vision and computer graphics tasks. This paper presents a novel online video background identification method with the assistance of inertial measurement unit (IMU). Based on the fact that the background motion of a video essentially reflects the 3D camera motion, we leverage IMU data to realize a robust camera motion estimation for identifying background feature points by only investigating a few historical frames. We observe that the displacement of the 2D projection of a scene point caused by camera rotation is depth-invariant, and the rotation estimation by using IMU data can be quite accurate. We thus propose to analyze 2D feature points by decomposing the 2D motion into two components: rotation projection and translation projection. In our method, after establishing the 3D camera rotations, we generate the depth-relevant 2D feature point movement induced by the camera 3D translation. Then, by examining the disparity between inter-frame offset and the projection of estimated 3D camera motion, we can identify the background feature points. In the experiments, our online method is able to run at 30FPS with only 1 frame latency and outperforms state-of-the-art background identification and other relevant methods. Our method directly leads to a better camera motion estimation, which is beneficial to many applications like online video stabilization, SLAM, image stitching, etc.

12.
BMC Cancer ; 22(1): 710, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35764956

RESUMO

BACKGROUND: Perioperative chemotherapy (ChT) and preoperative chemoradiation (CRT) are both the standard treatments for locally advanced gastric cancer (LAGC). CRT can achieve a higher pathological complete regression (pCR) rate, but whether this higher pCR rate can be transformed into a long-term survival benefit remains inconclusive. Therefore, relevant studies are in progress. On the other hand, immunotherapy has been established for the first-line treatment of advanced gastric cancer (AGC) and has been widely explored in the perioperative setting. The combination of chemotherapy/radiotherapy and immunotherapy may have a synergistic effect, which will lead to a better antitumor effect. The preliminary reports of ongoing studies show promising results, including a further improved pCR rate. However, the preferred treatment combination for LAGC is still not established. To solve this problem, we are carrying out this randomized phase II trial, which aims to evaluate the efficacy and safety of perioperative chemotherapy plus the use of PD-1 antibody with or without preoperative chemoradiation for LAGC. METHODS: Eligible patients with LAGC or gastroesophageal junction (GEJ) adenocarcinoma were randomized to receive perioperative ChT, PD-1 antibody, surgery with (Arm A) or without preoperative CRT (Arm B), and PD-1 antibody maintenance until one year after surgery. The primary endpoint of this study is that the pCR rate of Arm A will be significantly higher than that of Arm B. The secondary endpoints include the pathological partial regression (pPR) rate, R0 resection rate, objective response rate (ORR), event-free survival (EFS), overall survival (OS), safety and surgical complications. Moreover, several explorative endpoints will be evaluated to find and validate the predictive biomarkers of immunotherapy. DISCUSSION: The results of the NeoRacing study will provide important information concerning the application of PD-1 antibody in LAGC patients during the perioperative setting. Meanwhile, the two treatment protocols will be compared in terms of efficacy and safety. TRIAL REGISTRATION: ClinicalTrials.gov , NCT05161572 . Registered 17 December 2021 - Retrospectively registered.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ensaios Clínicos Fase II como Assunto , Neoplasias Esofágicas , Junção Esofagogástrica/patologia , Humanos , Imunoterapia/efeitos adversos , Receptor de Morte Celular Programada 1/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Gástricas/patologia
13.
Mitochondrial DNA B Resour ; 7(5): 878-880, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692709

RESUMO

Both Epimedium sutchuenense Franch. 1894 and E. fargesii Franch. 1894 are perennial herbs with excellent ornamental values due to their showy flowers. However, little molecular research has been done on these species. Here, the complete chloroplast (cp) genome of E. sutchuenense and E. fargesii was analyzed and reported. The cp genome sizes of E. sutchuenense and E. fargesii were 157, 263 and 157, 133 bp, respectively. Both the two cp genomes contained a pair of inverted repeat regions (IRs) (25,782 and 25,796 bp), separated by the small single-copy (SSC) region (17,106 and 17,071 bp) and a large single-copy (LSC) region (88,593 and 88,470 bp). A total of 113 unique genes were annotated in each of the two cp genomes, including 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. Phylogenetic analysis supported a close relationship between E. sutchuenense and E. wushanense, while E. fargesii had no clear clustering branch.

14.
Am J Cancer Res ; 12(5): 2363-2375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693073

RESUMO

Immunotherapies that block PD-L1/PD-1 immune checkpoint proteins represent a landmark breakthrough in cancer treatment. Although the role of PD-L1 in suppressing T cell activity has been extensively studied, its cancer cell-intrinsic functions are not well understood. Herein, we demonstrated that PD-L1 is important for the repair of DNA damage in cancer cells. Mechanically, depletion of PD-L1 led to the downregulation of the critical molecules involved in the homologous recombination (HR) repair pathway, such as ATM and BRCA1, but did not obviously affect the non-homologous end joining (NHEJ) pathway. Notably, PD-L1 silence sensitized cancer cells to chemotherapy agents and the inhibitor of DNA-PK, which is an important kinase for NHEJ. Furthermore, PD-L1 depletion potentiated DNA damage-induced cGAS-STING pathway and induction of IFNß. The regulation of DNA repair and cGAS-STING pathway by PD-L1 represents its connection with innate immunity that can be exploited to enhance the efficacy of existing immunotherapy. Our findings thus expand the focus of PD-L1 from tumor antigen-specific CD8+ T cells to innate immunity, and support targeting tumor-intrinsic PD-L1 combined with DNA-PK inhibition for tumor eradication, through promoting synthetic lethality and innate immune response.

15.
Front Genet ; 13: 836509, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669197

RESUMO

Background: Cervical cancer (CC) is the most common gynecological malignancy. Recently, an increasing number of studies have indicated that osteopontin (OPN) is a promising diagnostic and prognostic biomarker for CC. However, the biological role and detailed mechanism of OPN in CC remain unclear. Methods: The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets and a clinical sample microarray were used in our study. To identify the clinicopathological characteristics of OPN in CC, we compared the expression of OPN between normal and CC tissue samples and analyzed the correlations between OPN expression and multiple clinicopathological features. To identify biological processes involving OPN, OPN-associated genes were screened with Pearson correlation analysis and applied in hallmark gene set enrichment analysis (GSEA). Additionally, leukocyte infiltration was evaluated based on OPN expression. Finally, OPN-related signaling pathways were identified by GSEA. Results: OPN expression was higher in CC samples than in normal tissue samples and positively correlated with age, FIGO stage, tumor size, lymphovascular invasion and an unfavorable prognosis. OPN-associated genes were mainly enriched in the immune response, and increased OPN expression was accompanied by increased M2 macrophage infiltration. Additionally, OPN was correlated with hypoxia, high glycolytic metabolism, apoptosis, angiogenesis, epithelial-mesenchymal transition and multiple signaling pathways (the p53 pathway, the PI3K/Akt pathway, IL6/STAT3 signaling, mTORC1 signaling and KRAS signaling). Conclusion: Our study showed that OPN is involved in immunological activities and multiple tumor processes, identifying it as a potential therapeutic target and useful prognostic factor in CC patients.

16.
Front Plant Sci ; 13: 840061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651771

RESUMO

The plant cuticle, as a lipid membrane covering aerial plant surfaces, functions primarily against uncontrolled water loss. Herein, the cuticle chemical composition and the transpiration of wampee fruit (Clausena lansium (Lour.) Skeels) at the green, turning, and yellow stages in cultivars of "Jixin" and "Tianhuangpi" were comprehensively studied. The coverage of wax and cutin monomers per unit of fruit surface area at the green stage was lower in "Jixin" than in "Tianhuangpi" and increased gradually during development. Cutin monomers accumulated ranging from 22.5 µg cm-2 (green) to 52.5 µg cm-2 (turning) in "Jixin" and from 36.5 µg cm-2 (green) to 81.7 µg cm-2 (yellow) in "Tianhuangpi." The total composition of waxes ranged between 6.0 µg cm-2 (green) and 11.1 µg cm-2 (turning) in "Jixin," while they increased from 7.4 µg cm-2 (green) to 16.7 µg cm-2 (yellow) in "Tianhuangpi." Cutin monomers were dominated by ω-, mid-dihydroxy fatty acids (over 40%), followed by multiple monomers of α,ω-dicarboxylic acids with or without added groups, α-monocarboxylic acids with or without ω- or mid-chain hydroxy or mid-epoxy groups, primary alcohols, and phenolics. The very-long-chain (VLC) aliphatic pattern of cuticular waxes was prominently composed of n-alkanes (ranging from 21.4% to 39.3% of total wax content), fatty acids, primary alcohols, and aldehydes. The cyclic waxes were dominated by triterpenoids (between 23.9 and 51.2%), sterols, and phenolics. Water loss in wampee fruit exhibited linear changes over time, indicating an overall monofunctional barrier to transpiration. Permeance for water in wampee fruit was higher at the green stage than at the yellow stage in both "Jixin" and "Tianhuangpi," which showed a negative correlation with the changes of VLC n-alkanes. The results showed the cuticular chemicals, including cutin monomers and waxes, in wampee fruit and further indicated the potential contributions of the cuticular chemical composition to the physiological functions in fruits.

17.
Quant Imaging Med Surg ; 12(6): 3288-3299, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35655827

RESUMO

Background: A prerequisite to translating intravoxel incoherent motion (IVIM) imaging into meaningful clinical applications is sufficient scan-rescan reproducibility. This study aims to confirm the hypothesis that IVIM data fitting by not using b=0 images will improve the stability of liver IVIM measurement. Methods: Healthy volunteers' liver IVIM images were prospectively acquired using a 1.5-T magnet or a 3.0 T with 16 b-values. Repeatability study subjects were scanned twice during the same session, resulted in 35 paired scans for 35 subjects (11 men, mean age: 41.82 years, range: 32-60 years; 24 women, mean age: 42.67 years, range: 20-71 years). IVIM analysis was performed with full-fitting and segmented-fitting with a threshold b-value of 60 s/mm2, and fitting started from b=0 s/mm2 or from b=2 s/mm2. Reproducibility study subjects were scanned and then rescanned with an interval of 5-18 days, resulted in 20 paired scans for 11 subjects (4 men, mean age: 26.25 years, range: 25-27 years; 7 women, mean age: 25.57 years, range: 24-27 years). IVIM analysis was performed with segmented-fitting with a threshold b-value of 50 s/mm2, and fitting started from b=0 s/mm2 or from b=3 s/mm2. Results: Fitting without b=0 data generally improved the repeatability and reproducibility for both PF and Dslow, and particularly so for PF. For with b=0 data segmented fitting repeatability, PF had within-subject standard deviation of 0.019, bland-Atman 75% agreement limit of -31.52% to 28.35%, and ICC of 0.647, while these values were 0.009, -20.78% to 16.86%, and 0.837 for without b=0 analysis. Though the repeatability and reproducibility for Dfast generally also improved, they remained suboptimal. Measurement stability was better for repeatability than for reproducibility. Conclusions: Scan-rescan repeatability and reproducibility of liver IVIM parameters can be improved by fitting without b=0 data, which is particularly so for PF.

19.
Front Surg ; 9: 860150, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35495741

RESUMO

Background: Stapler hemorrhoidopexy (SH) has been widely accepted for hemorrhoids patients because of its low postoperative pain, but it is also associated with a high recurrence rate. The recurrence might be due to failure to completely remove the prolapsed tissue or insufficient removal capacity of the instruments. Removing more prolapsed tissue to reduce the recurrence is believed to benefit more severe prolapsed hemorrhoids patients. Methods: We evaluated the short- and long-term safety and efficacy in 125 hemorrhoids patients who underwent SH in 2013-2015. Eighty patients had prolapsed tissue less than half of the circular anal dilator (CAD) and underwent a procedure for prolapsing hemorrhoids (PPH), while the remaining 45 patients with hemorrhoid prolapse greater than half of the CAD were treated with a tissue selection therapy stapler stapled transanal rectal resection plus (TST STARR+). Results: There were no significant differences between the two groups in terms of operative time, hospitalization time, overall satisfaction or complications. At follow-up of up to 4 years after surgery, there was no significant difference in recurrence rates between TST STARR+ group and PPH group (5.2% vs. 4.7%, p < 0.05). The mean width and volume of the resected tissues were significantly larger in the TST STARR+ group than in the PPH group (4.8 vs. 2.9 cm, 10.2 vs. 4.4 cm3, P < 0.05). Conclusion: The TST STARR+ procedure can remove more hemorrhoidal tissue than PPH and it is better suited for patients with severe annular prolapsed hemorrhoids greater than half of the CAD. It has the advantages of convenient to operate, rapid recovery, fewer complications, and long-term satisfactory results.

20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(2): 301-310, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35523551

RESUMO

Electrocardiogram (ECG) can visually reflect the physiological electrical activity of human heart, which is important in the field of arrhythmia detection and classification. To address the negative effect of label imbalance in ECG data on arrhythmia classification, this paper proposes a nested long short-term memory network (NLSTM) model for unbalanced ECG signal classification. The NLSTM is built to learn and memorize the temporal characteristics in complex signals, and the focal loss function is used to reduce the weights of easily identifiable samples. Then the residual attention mechanism is used to modify the assigned weights according to the importance of sample characteristic to solve the sample imbalance problem. Then the synthetic minority over-sampling technique is used to perform a simple manual oversampling process on the Massachusetts institute of technology and Beth Israel hospital arrhythmia (MIT-BIH-AR) database to further increase the classification accuracy of the model. Finally, the MIT-BIH arrhythmia database is applied to experimentally verify the above algorithms. The experimental results show that the proposed method can effectively solve the issues of imbalanced samples and unremarkable features in ECG signals, and the overall accuracy of the model reaches 98.34%. It also significantly improves the recognition and classification of minority samples and has provided a new feasible method for ECG-assisted diagnosis, which has practical application significance.


Assuntos
Memória de Curto Prazo , Redes Neurais de Computação , Algoritmos , Arritmias Cardíacas/diagnóstico , Eletrocardiografia , Humanos , Processamento de Sinais Assistido por Computador
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