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1.
Cancer Lett ; 468: 88-101, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593800

RESUMO

Dysregulation of circular RNA Foxo3 (circFoxo3) has been reported to be involved in breast cancer and non-small lung cancer progression. However, little is known about the role of circFoxo3 in prostate cancer, which the present study seeks to investigate. CircFoxo3 expression was analyzed in 22 low-grade prostate cancer samples, 24 high-graded prostate cancer samples, and 18 normal prostate tissues, finding that its quantity was significantly decreased in high-graded compared to low-grade prostate cancer and normal prostate tissues. CircFoxo3 inhibited prostate cancer cell survival, migration, invasion and chemoresistance to docetaxel, which was related to circFoxo3's repression of Foxo3 and EMT. Silencing circFoxo3 expression promoted prostate cancer cell survival, migration, invasion and chemoresistance to docetaxel, as well as the positive effects of androgen on prostate cancer viability. Delivery of circfoxo3 enhanced chemosensitivity to docetaxel of prostate tumor-bearing mice and prolonged the life span of mice, while reduction with siRNAs promoted chemoresistance to docetaxel and shorted the life span of the tumor-bearing mice. Targeting circFoxo3/Foxo3/EMT may provide an applicable strategy for exploring potential prognostic and therapeutic approaches for prostate cancer.

2.
Cytokine ; 125: 154801, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31442680

RESUMO

BACKGROUND: HIV rapid progressors (RPs) present with a rapid decline of CD4+ T cells within a few years of infection. Determining the underlying mechanisms throughout this decline is important to identify prognostic biomarkers and intervention strategies. Determining the numbers of CD4+ and CD8+ T cells is essential for monitoring the immune status of HIV infected patients. There are additional kinds of cell subtypes in T cells, but their relationship to the rapid progression of HIV disease is not well defined. METHODS: Nineteen RPs and twenty-one chronic progressors (CPs) were enrolled in this study. Based on the intensity of CD4 and CD8 expression, different T cell subtypes were identified, including CD4+CD8+T cells, CD4-CD8- T cells, CD4+CD8low T cells and CD4-CD8low T cells. Alterations in these T cell subtypes in early HIV infection (within 120 days of infection) between RPs and CPs were measured, and the relationships between these subtypes and HIV disease progression were investigated. In addition, expression of IFN-γ in T cell subtypes after PMA stimulation was analyzed by flow cytometry. RESULTS: We found that during early HIV infection, CD4+CD8low T cells both significantly decreased in numbers and percentages in RPs compared to CPs. Furthermore, baseline CD4+CD8low T cells positively correlated not only with baseline CD4+T cells but also with CD4+T cells 12 months after infection. Moreover, survival analysis indicated that low levels of baseline CD4+CD8low T cells significantly accelerated the decline in CD4+ T cells as well as increased viral loads. CD4+CD8low T cells secreted significantly more IFN-γ after PMA stimulation compared to CD4+CD8-T cells and CD4-CD8+T cells, which may be beneficial for the prevention of disease progression. CONCLUSIONS: Our results identified that in early stage HIV-1 infection, a subtype of T cells, CD4+CD8low, are associated with subsequent disease progression.

3.
Opt Express ; 27(21): 30530-30551, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684299

RESUMO

Due to either coherent or dissipative interactions with the coherent population trapping (CPT)-based atoms, the evolutions of the Bogoliubov modes towards the vacuum states have been shown to lead to second-order squeezing of the involved optical fields. Here we push the CPT-based dissipative interactions towards higher-order squeezing, which is not simply determined by second-order squeezing but instead by different criteria involving higher-order moments. It is shown that the CPT-based atomic reservoir supports the dissipative evolution of the Bogoliubov modes almost completely to the vacuum states and then yields almost perfect fourth-order squeezing (90%∼100%). The present mechanism is robust against spontaneous emission since the atoms stay largely in the ground states. As a by-product, a comparison is given with two-level atoms, in which the excitation of a large fraction reduces the degree of higher-order squeezing.

4.
Opt Express ; 27(22): 31407-31417, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684375

RESUMO

The electromagnetic field theory for a step-index fiber geometry is developed to sense a surrounding chiral drug via long-period fiber gratings (LPFGs). This theory employs Debye potentials and electromagnetic fields for cladding modes in the LPFGs by introducing constitutive relations for a chiral drug. The fields in the chiral drug are transformed and decomposed into right- and left-hand circularly polarized components to account for the magnetoelectric coupling due to the chirality. The solving process for complex propagation constants is given. Numerical results show that responses of the LPFGs to refractive index and chirality changes are different. The two minimum transmissions of a coated LPFG are very sensitive to the variation of the complex chirality. On the other hand, the two resonance wavelengths keep invariant as real and imaginary parts of the comparatively small chirality change. This work enriches the electromagnetic field theory for better design of LPFGs against the highly sensitive chirality detection.

5.
Bioorg Chem ; : 103420, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31718890

RESUMO

A concise total synthesis of an exceedingly potent anti-inflammatory agent violacin A as well as the preparation of thirty analogues of this lead from commercially available orcinol are described. Highlights of our synthetic efforts involve Friedel-Crafts acylation, the regioselective etherification and esterification of phenolic hydroxyl groups, and Baker-Venkatamaran rearrangement to form basic skeleton of violacin A. The deprotection reaction with Pd-catalytic was involved to avoid the elimination of the hemiacetal hydroxyl at C2. In addition, all synthetic compounds were screened for anti-inflammatory activity against nitric oxide (NO) production using lipopolysaccharide (LPS)-induced Raw264.7 cells. A range of violacin A derivatives 11b, 11d, 11f, 12e, 12g, 13g, 17d-g exhibited stronger anti-inflammatory effect than that of violacin A. Notably, halogeno-benzyloxy substituent at C-7 were favourable for anti-inflammatory activities of violacin A derivatives. Additionally, Western blot results indicated halogeno-benzyloxy derivatives inhibited pro-inflammatory cytokines releases correlated with the suppression of NF-κB signaling pathway.

6.
Environ Sci Technol ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31684725

RESUMO

Increasing numbers of novel pesticides have been applied in agriculture. However, traditional evaluation of pesticides does not distinguish between their enantiomers, which may lead to inaccurate results. In this study, systematic research on the chiral insecticide fluxametamide was conducted at the enantiomeric level. The methods for enantioseparation and semipreparative separation of fluxametamide enantiomers were developed. The optical rotation and absolute configuration of two enantiomers were determined, and their stability was verified in solvents and soils. Enantioselective bioactivities against four target pests (Plutella xylostella, Spodoptera exigua, Aphis gossypii, and Tetranychus cinnabarinus) were tested. Acute toxicities of fluxametamide enantiomers toward honeybees were also evaluated. S-(+)-Isomer exhibited 52.1-304.4 times and 2.5-3.7 times higher bioactivity than R-(-)-isomer and rac-fluxametamide, respectively. Meanwhile, rac-fluxametamide was more toxic than S/R-isomer, and S-(+)-isomer showed >30-fold higher acute toxicity than R-(-)-isomer. Molecular docking studies were performed with γ-aminobutyric acid receptor (GABAR) to monitor the mechanism of stereoselective bioactivity. The better Grid score of S-(+)-fluxametamide (-60.12 kcal/mol) than R-(-)-enantiomer (-56.59 kcal/mol) indicated higher bioactivity of S-(+)-isomer than of R-(-)-isomer. The dissipation of fluxametamide in cabbage, Chinese cabbage, and soil was nonenantioselective under field conditions. Development of S-(+)-fluxametamide could maintain the high-efficacy and low-risk properties, which should attract attention of producers, applicators, and managers of pesticides.

7.
Orphanet J Rare Dis ; 14(1): 245, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699117

RESUMO

BACKGROUND: Differentiation between pancreatic cancer (PC) and focal form of autoimmune pancreatitis (AIP) is very challenging, with similar clinical presentations, laboratory results and morphologic imagings of US, CT, EUS, MRI, ERCP, PET-CT. Even serum IgG4 and biopsy sometimes cannot give clear-cut differential accurate diagnostis. Considering the totally different management strategy of the two diseases, accurate diagnostic value is urgently needed to remind the clinicians of the rare diagnosis of untypical AIP among frequent PC-suspected patients. RESULTS: We present 2 laparotomy cases of AIP that had a high similar characteristic to PC and retrospectively extracted the warning signs that may help select untypical AIP in PC-suspected patients. CONCLUSIONS: We find that mild fluctuating jaundice with abdominal pain, young age, tumor marker of TPS, TPA and diverse results between variable radiological tests can help to differentiate AIP mass from PC, through retrospectively analyzing work-up process of AIP in two patients who underwent laparotomy for suspected PC.

8.
J Cell Biochem ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31691355

RESUMO

Accepted as a malignant tumor worldwide, cervical cancer (CC) has attracted much attention for its high incidence and mortality rates. Previous studies have elucidated the critical regulatory function that long noncoding RNAs (lncRNAs) exert on the tumorigenesis and progression of diverse tumors. Although multiple investigations have depicted that LINC00958 has a great impact on the complex biological process of many cancers, knowledge concerning the regulatory role of LINC00958 in CC remains limited and needs to be further explored. In our study, LINC00958 expression was evidently overexpressed in CC tissues and cells. Besides this, LINC00958 negatively regulated miR-625-5p expression and was verified to bind with miR-625-5p in CC. Subsequently, it was testified by a series of experiments that LINC00958 promotes CC cell proliferation and metastasis by sponging miR-625-5p. Furthermore, the leucine-rich repeat containing the eight family member E (LRRC8E) could bind with miR-625-5p, and its expression was negatively modulated by miR-625-5p, whereas positively regulated by LINC00958 in CC. Final rescue assays verified the effects of LINC0095/LRRC8E interaction and miR-625-5p/LRRC8E interaction on CC cell proliferation and metastasis. Collectively, LINC00958 facilitates CC cell proliferation and metastasis via the miR-625-5p/LRRC8E axis.

9.
Urol Oncol ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31672485

RESUMO

OBJECTIVE: Docetaxel-based chemotherapy remains the first-line treatment for patients with metastatic castration-resistant prostate cancer (mCRPC) in China. We have previously shown that time to nadir (TTN) of prostate-specific antigen (PSA) is an important prognostic factor in patients from a single center in Northwestern China. In this study, we performed a multicenter validation of the prognostic role of TTN in additional Chinese patients with mCRPC receiving docetaxel treatment. MATERIALS AND METHODS: The data were gathered from 170 eligible Chinese patients who received docetaxel chemotherapy from January 2007 to October 2018 in 11 Chinese Prostate Cancer Consortium member hospitals in China. TTN was defined as the time from start of chemotherapy to the nadir of PSA level during the treatment. Multivariable Cox regression models and Kaplan-Meier analysis were used to predict overall survival (OS) and progression-free survival (PFS). RESULTS: Patients with a TTN ≥ 15 weeks had a longer OS and PFS compared to those with a TTN < 15 weeks (43 vs. 15 months, P < 0.001; 24 vs. 6 months, P < 0.001, respectively). In addition, Patients with a TTN ≥ 15 weeks and PSA nadir <4.55ng/ml were associated with longer OS than others (HR 0.093, 95% CI 0.044-0.188, P < 0.001; HR 4.002, 95% CI 1.890-8.856, P = 0.001, respectively) and TTN, PSA nadir, PSA baseline (optimal threshold 56.07 ng/ml), and PSA reduction (optimal threshold 50%) were associated with PFS (HR 0.238, 95% CI 0.149-0.382, P < 0.001; HR 1.676, 95% CI 1.033-2.722, P = 0.037; HR 1.770, 95% CI 1.134-2.763, P = 0.012; HR 0.573, 95% CI 0.428-0.756, P < 0.001; respectively). Furthermore, patients with a PSA nadir <4.55 ng/ml had longer OS and PFS compared to other patients when TTN was ≥15 weeks. CONCLUSION: In this multicenter validation study, TTN and PSA nadir remain important prognostic markers in predicting therapeutic outcomes in Chinese men who receive chemotherapy for mCRPC.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31715023

RESUMO

BACKGROUND: Post-operative cognitive dysfunction (POCD) is a decline of cognitive status that commonly occurs after surgery in elderly patients. Whether DNA methylation is associated with the development of POCD remains unclear. METHODS: Subjects (N = 124) older than 65 years-of-age undergoing hip replacement surgery were enrolled. A battery of neuropsychiatric tests was used to examine the perioperative cognitive function of the patients. Early POCD was analyzed using the reliable change index (RCI), and subjects were diagnosed with POCD if RCI < -1.96. Peripheral leukocyte DNA was isolated, and DNA methylation was measured via 5-methylcytosine (mC) using Elisa. RESULTS: Twenty-four patients (19.4%) developed early POCD. There was no difference in baseline 5-mC levels by POCD status. The 5-mC levels significantly decreased on day 7 after surgery in patients who developed early POCD (P = .004), but did not change in non-POCD patients. Moreover, post-operative 5-mC levels were significantly lower in POCD patients than those in non-POCD patients (P = .003). Bivariate logistic models adjusted for age, gender, BMI, duration of anesthesia, and education level clearly demonstrated an independent association between post-operative 5-mC level and early POCD. CONCLUSIONS: Post-operative global hypomethylation of leukocyte DNA was associated with the development of early POCD. TRIAL REGISTRATION: ClinicalTrial, NCT02965235. Registered 16 November 2016, https://www.clinicaltrials.gov/ct2/results?term=NCT02965235&rank=1#rowId0.

11.
Biomed Pharmacother ; 121: 109368, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31707348

RESUMO

Hypertension is an essential regulator of cardiac injury and remodeling. However, the pathogenesis that contributes to cardiac hypertrophy remains to be fully explored. BRD4, as a bromodomain and extra-terminal (BET) family member, plays an important role in critical biological processes. In the study, our results showed that BRD4 expression was up-regulated in human and mouse hypertrophied hearts, and importantly these effects were modulated by reactive oxygen species (ROS) generation. In angiotensin II (Ang II)-treated cardiomyocytes, BRD4 decrease markedly blunted the prohypertrophic effect, which was further promoted by the combinational treatment of ROS scavenger (N-acetyl-cysteine, NAC). In addition, NAC pre-treatment markedly elevated the anti-fibrotic role of BRD4 suppression in Ang II-incubated cardiomyocytes by repressing transforming growth factor ß1 (TGF-ß1)/SMADs signaling pathway. NAC combined with BRD4 reduction further alleviated inflammation and oxidative stress in Ang II-exposed cardiomyocytes, which was partly through inhibiting nuclear factor-κB (NF-κB) signaling and improving nuclear erythroid factor 2-related factor 2 (Nrf-2)/heme oxygenase-1 (HO-1) pathway, respectively. Furthermore, the in vivo results confirmed the protective effects of BRD4 suppression on mice against aortic banding (AB)-induced cardiac hypertrophy, as evidenced by the reduced cross sectional area and fibrotic area using H&E and Masson trichrome staining. What's more, the degree of cardiac hypertrophy (ANP and BNP), the expression of pro-fibrotic genes (TGF-ß1, Collagen I, Collagen III and CTGF), the levels of inflammation and oxidative stress were all significantly attenuated by the blockage of BRD4 in AB-operated mice. Taken together, repressing BRD4 expression was found to confer a protective effect against experimental cardiac hypertrophy in mice, demonstrating its potential as an effective therapeutic target for pathological cardiac hypertrophy.

12.
Sci Total Environ ; 702: 134767, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31726335

RESUMO

The aim of the present study was to investigate the sorption of atrazine and nicosulfuron onto several experimentally produced biochars, as well as to understand the influence of biochar structure on sorption mechanisms. Nine biochars were generated by pyrolyzing peanut shell at 300, 450, or 600 °C and exposing samples to each of the several deashing treatments: none, water or HCl. The sorption of atrazine and nicosulfuron by the nine biochars were evaluated. Biochars were characterized via elemental analyzer, BET-N2 surface area, FTIR and XPS. Three kinetic models were used to fit the sorption kinetics data and both the Freundlich and dual-mode models described the sorption isotherms well. All the biochar samples exhibited high sorption affinity for both atrazine and nicosulfuron. The sorption mechanisms of the biochar included hydrophobic partition, π-π electron donor-acceptor interactions, H-bonding, and pore-filling mechanism, and these mechanisms were dependent on both the degree of biochar carbonization and the concentration of atrazine or nicosulfuron. Ash could bind to atrazine and nicosulfuron by specific interactions but played a negative role in the sorption, especially on high pyrolyzing temperature biochars. These results will facilitate the production of efficient and cheap adsorbents for reducing the risk of atrazine and nicosulfuron.

13.
Clin Chim Acta ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31730819

RESUMO

OBJECTIVE: To investigate the association of D-dimer level during late pregnancy with birth outcomes in a Chinese population. METHODS: A retrospective observational cohort study of 11,570 pregnant women who delivered in a single central hospital was conducted. Maternal plasma D-dimer levels at hospital admission and pregnancy outcomes were abstracted and analyzed from laboratory information system and hospital records, respectively. RESULTS: Maternal plasma D-dimer levels were associated with higher fetal growth indicators for the highest vs. lowest quartile (Q) of D-dimer (mean birth weight: 145.79 g, mean birth length: 0.11 cm, mean gestational age: 0.30 week). Increase in D-dimer quartiles were associated with an decreased risk for small for gestational age (SGA), low birth weight (LBW) and preterm birth (PTB) neonates, and with an increased risk for large for gestational age (LGA), and macrosomia infants (SGA: OR = 0.52, 95% CI: 0.43, 0.64; LBW: OR = 0.58, 95% CI: 0.38, 0.86; PTB: OR = 0.44, 95% CI: 0.35, 0.55; LGA: OR = 2.37, 95% CI: 2.01, 2.78; macrosomia: OR = 2.59, 95% CI, 2.06, 3.24; for Q4 vs. Q1). CONCLUSION: Maternal plasma D-dimer levels during late pregnancy were associated with birth outcomes and had risk evaluation value for these outcomes.

14.
PLoS One ; 14(11): e0224730, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31725747

RESUMO

AIM: To confirm the effects of Debaryomyces hansenii on intestinal microecology in mice with antibiotic-associated diarrhea (AAD). METHODS: This study took the mucosal microecology as the entry point and an antibiotic mixture was used to induce diarrhea in mice. D. hansenii suspension was used to treat the mice and the bacterial communities of mucosa was analyzed using high-throughput sequencing. RESULTS: The Shannon-Wiener index indicated that the sequencing depth is reasonable and reflected the majority of microbial information. The principal coordinate analysis results showed that mice in the treatment group and the normal group had a similar microbial community structure, while differences in microbial community structure were observed between the model group and the treatment group. The inter-group bacterial structures were analyzed at the phylum level and genus level. The results revealed that antibiotic treatment increased the proportion of Proteobacteria and decreased the proportion of Bacteroides, while D. hansenii treatment inhibited the increase in Proteobacteria. Linear discriminant analysis coupled with effect size measurements (LEfSe) suggested d that the beneficial bacteria Candidatus Arthromitus were the only common bacteria in the normal group (P<0.05). CONCLUSION: The treatment with D.hansenii could contribute to the maintenance of the structure of the mucosal microbiota in comparison with the normal group and inhibit the proliferation of opportunistic bacteria. However, high-dose antibiotic treatment causes mucosal dysbiosis and the proliferation of opportunistic bacteria during the self-recovery period, such as Pseudoalteromonas, Alteromonas, Vibrio.

15.
J Hazard Mater ; : 121630, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31744725

RESUMO

The ultrasensitive detection and efficient degradation of tetracycline (TC) residues are important for improving food safety and protecting human health. In this paper, a smart silver-enhanced fluorescence platform for the ultrasensitive detection of TC was constructed via a simple and selective modification of the interior and external tubes of natural halloysite nanotubes. The thick pipe wall of this platform provides a natural defense and promotes metal-enhanced fluorescence effects, which subsequently accelerates the detection of TC. Moreover, the nanoplatform of the modified Ag nanoparticles can induce the separation of electrons and holes, thereby enhancing photocatalytic activity in TC degradation. This platform provides new opportunities for studying natural halloysite nanotubes and for simultaneously detecting and photodegrading other deleterious substances.

16.
Adv Mater ; : e1903945, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746050

RESUMO

Silicon and other inorganic semiconductor nanowires (NWs) have been extensively investigated in the last two decades for constructing high-performance nanoelectronics, sensors, and optoelectronics. For many of these applications, these tiny building blocks have to be integrated into the existing planar electronic platform, where precise location, orientation, and layout controls are indispensable. In the advent of More-than-Moore's era, there are also emerging demands for a programmable growth engineering of the geometry, composition, and line-shape of NWs on planar or out-of-plane 3D sidewall surfaces. Here, the critical technologies established for synthesis, transferring, and assembly of NWs upon planar surface are examined; then, the recent progress of in-plane growth of horizontal NWs directly upon crystalline or patterned substrates, constrained by using nanochannels, an epitaxial interface, or amorphous thin film precursors is discussed. Finally, the unique capabilities of planar growth of NWs in achieving precise guided growth control, programmable geometry, composition, and line-shape engineering are reviewed, followed by their latest device applications in building high-performance field-effect transistors, photodetectors, stretchable electronics, and 3D stacked-channel integration.

17.
World Neurosurg ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31678437

RESUMO

BACKGROUND: Neurofibromatosis type 1 (NF1), a dysregulated neurocutaneous disorder, is an autosomal dominant genetic diease caused by mutations in the NF1 gene. Anaplastic astrocytoma is very rare in NF1 patients and research has proposed that high-grade astrocytomas could be due to larger germ-line mutations in NF1.We present a clinical and molecular study of a Chinese family with NF1. CLINICAL CASE: A 28-year-old male patient with neurofibromatosis type 1 presents with headache, vertigo and dizziness. Histopathological examination and molecular features identified a cerebellar anaplastic astrocytoma, IDH-wildtype. The patient underwent gross total resection of the lesion and received radiotherapy and chemotherapy. A rare splice error mutation (c.4110+945A>G) in intron 23-2 of NF1 was identified by next-generation sequencing in the proband and was identified and confirmed by Sanger sequencing in some affected family members. CONCLUSIONS: We present a unique case of NF1 with anaplastic astrocytoma and revealed a rare splice error mutation in NF1 gene in the family.

18.
Stroke ; : STROKEAHA119027115, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31679502

RESUMO

Background and Purpose- Studies on the prevalence and risk factors of white matter lesions (WMLs) in Tibetans living at high altitudes are scarce. We conducted this study to determine the prevalence and risks of WMLs in Tibetan patients without or with nonacute stroke. Methods- We undertook a retrospective analysis of medical records of patients treated at the People's Hospital of Tibetan Autonomous Region and identified a total of 301 Tibetan patients without acute stroke. WML severity was graded by the Fazekas Scale. We assessed the overall and age-specific prevalence of WMLs and analyzed associations between WMLs and related factors with univariate and multivariate methods. Results- Of the 301 patients, 87 (28.9%) had peripheral vertigo, 83 (27.3%) had primary headache, 52 (17.3%) had a history of stroke, 36 (12.0%) had an anxiety disorder, 29 (9.6%) had epilepsy, 12 (4.0%) had infections of the central nervous system, and 3 (1.0%) had undetermined diseases. WMLs were present in 245 (81.4%) patients, and 54 (17.9%) were younger than 40 years. Univariate analysis showed that age, history of cerebral infarction, hypertension, the thickness of the common carotid artery intima, and plaque within the intracarotid artery were related risks for WMLs. Ordered logistic analysis showed that age, history of cerebral ischemic stroke, hypertension, male sex, and atrial fibrillation were associated with WML severity. Conclusions- Risk factors for WMLs appear similar for Tibetans residing at high altitudes and individuals living in the plains. Further investigations are needed to determine whether Tibetans residing at high altitudes have a higher burden of WMLs than inhabitants of the plains.

19.
J Vis Exp ; (152)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31680679

RESUMO

Percutaneous vertebroplasty (PVP) is considered an effective treatment for the back pain caused by osteoporotic vertebral compression fracture. The accuracy of PVP mainly depends on the surgeons' experience and multiple fluoroscopes during a traditional procedure. Puncture related complications were reported all over the world. To make the surgical procedure more precise and decrease the rate of puncture-related complications, our team applied a three-dimensional printing guide template to PVP to modify the traditional procedure. This protocol introduces how to model target vertebrae DICOM imaging data into three-dimensions in the software, how to simulate operation in this 3-D model, and how to use all of the surgical data to reconstruct a patient specific template for application. Using this template, surgeons can identify suitable puncture points accurately to improve the accuracy of the operation. The whole protocol includes: 1) diagnosis of the osteoporotic vertebral compression fracture; 2) acquisition of CT imaging of the target vertebra; 3) simulation of the operation in the software; 4) design and fabrication of the 3-D printing guide template; and 5) application of the template into an operation procedure.

20.
J Opt Soc Am A Opt Image Sci Vis ; 36(10): 1795-1800, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674446

RESUMO

To solve the imaging distortion problem in a nonuniform temperature field for visual measurement, this paper studies the Runge-Kutta ray tracing algorithm. First, the light ray emitted by the spatial light point will be abstracted by the proposed method. Then, the ray trajectory in a 3D nonuniform temperature gradient environment will be reproduced, and the ray distortion can be corrected. Finally, the distortion is compared with the actual image distortion obtained through the corner detection method. The experimental results show that the correction method for the distortion image caused by nonuniform temperature gradient heat source interference is feasible by using the Runge-Kutta ray tracing algorithm, which can realize the error compensation for image distortion and obtain an accurate corrected image.

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