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1.
J Nanosci Nanotechnol ; 20(2): 802-809, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383075

RESUMO

AgIO3/Ag2O/Ag nanocomposites with enhanced photocatalytic activities were synthesized by a onestep coprecipitation method at room temperature. The optimum hybrid of AgIO3/Ag2O = 1.25:1 with Ag nanoparticles (Ag NPs) loading (denoted as AA125) exhibited superior photocatalytic activity, demonstrating 97.19% tetracycline (TC) degradation within 60 min under simulated solar irradiation. This was approximately 10.44 and 2.63 times higher than that of pure Ag2O and AgIO3, respectively. The advanced photocatalytic activity can be ascribed to the synergetic effects of the heterostructured AgIO3/Ag2O/Ag and the strong surface plasmon resonance (SPR) effect of Ag NPs generated on the surface, which improved the separation and transfer efficiency of photoinduced electron-hole pairs. The results from radical scavenger experiments indicated that the degradation of TC was driven mainly by the participation of superoxide radical (·O-2).

2.
Artigo em Inglês | MEDLINE | ID: mdl-31494783

RESUMO

Water resource assessment is crucial for human well-being and ecosystem health. Assessments considering both blue and green water are of great significance, as green water plays a critical but often ignored role in the terrestrial ecosystem, especially in arid and semi-arid regions. Many approaches have been developed for green and blue water valuation; however, few approaches consider the interrelationship between green and blue water. This study proposed a new framework for green and blue water assessment by considering the interactions between green and blue water and the connections between human and natural ecosystems in an arid endorheic river basin where hydrological cycling is dramatically altered by human activities. The results show that even though green water is the dominant water resource, blue water is also critical. Most of the blue water is redirected back into the soil through physical and human-induced processes to meet the water demand of the ecosystem. The blue and green water regimes are found to be totally different in different ecosystems due to the temporal and spatial variability in water supply and consumption. We also found that humans are using an increasing proportion of water, resulting in decreasing water availability. Extensive water use by humans reduces the water availability for the natural ecosystem. Approximately 38.6% of the vegetation-covered area, which is dominated by farmland and forest, may face a moderate or high risk of increased conflict and tension over freshwater. This study provides crucial information to better understand the interactions between green and blue water and the relations between humans and nature by explicitly assessing water resources. It also provides crucial information for water management strategies that aim to balance humankind and nature.

3.
Opt Express ; 27(18): 24945-24952, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31510375

RESUMO

An ultrafast coherent long wavelength MIR source based on difference frequency generation was demonstrated. An average power of 2.5 mW at ∼18 µm was achieved. The angular distribution of the generated MIR source under the condition of tight-focusing limit shows the onset of conical emission of the MIR beam due to on-axis phase mismatching.

4.
Nature ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511693

RESUMO

Early human embryonic development involves extensive lineage diversification, cell-fate specification and tissue patterning1. Despite its basic and clinical importance, early human embryonic development remains relatively unexplained owing to interspecies divergence2,3 and limited accessibility to human embryo samples. Here we report that human pluripotent stem cells (hPSCs) in a microfluidic device recapitulate, in a highly controllable and scalable fashion, landmarks of the development of the epiblast and amniotic ectoderm parts of the conceptus, including lumenogenesis of the epiblast and the resultant pro-amniotic cavity, formation of a bipolar embryonic sac, and specification of primordial germ cells and primitive streak cells. We further show that amniotic ectoderm-like cells function as a signalling centre to trigger the onset of gastrulation-like events in hPSCs. Given its controllability and scalability, the microfluidic model provides a powerful experimental system to advance knowledge of human embryology and reproduction. This model could assist in the rational design of differentiation protocols of hPSCs for disease modelling and cell therapy, and in high-throughput drug and toxicity screens to prevent pregnancy failure and birth defects.

5.
PLoS One ; 14(7): e0220521, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31365582

RESUMO

The reliability of MyotonPRO that can monitor the mechanical properties of tissues is still unclear. This study aimed to analyze the within-day inter-operator and between-day intra-operator reliability of MyotonPRO for assessing tone and stiffness of quadriceps femoris and patellar tendon at different knee angles. The tone and stiffness of healthy participants (15 males and 15 females, aged 24.7±1.6 years) in the supine and resting position were measured using the MyotonPRO device. The measurements were quantified at 0°, 30°, 60°, and 90° of knee flexion. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable change (MDC) were calculated and a Bland-Altman analysis was conducted to estimate reliability. The results indicated excellent inter-operator reliability (ICC > 0.78) and good to excellent intra-operator reliability (ICC > 0.41). The inter-operator SEM measurements ranged between 0.1-0.9 Hz and 3.8-37.9 N/m, and intra-operator SEM ranged between 0.5-1.3 Hz and 7.9-52.0 N/m. The inter-operator MDC ranged between 0.3-2.5 Hz and 10.5-105.1 N/m, and intra-operator SEM ranged between 1.1-3.3 Hz and 21.9-144.1 N/m. The agreement of inter-operator was better than that of intra-operator. The study concluded that MyotonPRO is a reliable device to detect the tone and stiffness of quadriceps femoris and patellar tendon.

6.
Hum Cell ; 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31388923

RESUMO

This study aimed to investigate the role of lncRNA terminal differentiation-induced ncRNA (TINCR) in cervical squamous cell carcinoma (CSCC). By informatics analysis, we found that miR-302 may bind TINCR. Expression analysis showed that miR-302 was downregulated, while TINCR was upregulated in CSCC. Correlation analysis showed that they were not significantly correlated. In CSCC cells, miR-302 and TINCR failed to affect the expression of each other. However, miR-302 overexpression led to downregulated and TINCR overexpression led to upregulated cyclin D1 expression in CSCC cells. Interestingly, overexpression of cyclin D1 led to upregulated miR-302 and TINCR. Cell proliferation analysis showed that TINCR and cyclin D1 overexpression led to increased, while miR-302 overexpression led to decreased rate of cell proliferation. Moreover, miR-302 overexpression reduced the effects of TINCR overexpression. Therefore, TINCR sponges miR-302 to upregulate cyclin D1 in CSCC, thereby promoting cell proliferation.

7.
Sci Rep ; 9(1): 11666, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31406143

RESUMO

Imbalanced angiogenesis is a characteristic of several diseases. Rho GTPases regulate multiple cellular processes, such as cytoskeletal rearrangement, cell movement, microtubule dynamics, signal transduction and gene expression. Among the Rho GTPases, RhoA, Rac1 and Cdc42 are best characterized. The role of endothelial Rac1 and Cdc42 in embryonic development and retinal angiogenesis has been studied, however the role of endothelial RhoA is yet to be explored. Here, we aimed to identify the role of endothelial RhoA in endothelial cell functions, in embryonic and retinal development and explored compensatory mechanisms. In vitro, RhoA is involved in cell proliferation, migration and tube formation, triggered by the angiogenesis inducers Vascular Endothelial Growth Factor (VEGF) and Sphingosine-1 Phosphate (S1P). In vivo, through constitutive and inducible endothelial RhoA deficiency we tested the role of endothelial RhoA in embryonic development and retinal angiogenesis. Constitutive endothelial RhoA deficiency, although decreased survival, was not detrimental for embryonic development, while inducible endothelial RhoA deficiency presented only mild deficiencies in the retina. The redundant role of RhoA in vivo can be attributed to potential differences in the signaling cues regulating angiogenesis in physiological versus pathological conditions and to the alternative compensatory mechanisms that may be present in the in vivo setting.

8.
PLoS One ; 14(8): e0220186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31412071

RESUMO

Undergraduate research experiences (UREs) have the potential to benefit undergraduates and longer UREs have been shown to lead to greater benefits for students. However, no studies have examined what causes students to stay in or consider leaving their UREs. In this study, we examined what factors cause students to stay in their UREs, what factors cause students to consider leaving their UREs, and what factors cause students to leave their UREs. We sampled from 25 research-intensive (R1) public universities across the United States and surveyed 768 life sciences undergraduates who were currently participating in or had previously participated in a URE. Students answered closed-ended and open-ended questions about factors that they perceived influenced their persistence in UREs. We used logistic regression to explore to what extent student demographics predicted what factors influenced students to stay in or consider leaving their UREs. We applied open-coding methods to probe the student-reported reasons why students chose to stay in and leave their UREs. Fifty percent of survey respondents considered leaving their URE, and 53.1% of those students actually left their URE. Students who reported having a positive lab environment and students who indicated enjoying their everyday research tasks were more likely to not consider leaving their UREs. In contrast, students who reported a negative lab environment or that they were not gaining important knowledge or skills were more likely to leave their UREs. Further, we identified that gender, race/ethnicity, college generation status, and GPA predicted which factors influenced students' decisions to persist in their UREs. This research provides important insight into how research mentors can create UREs that undergraduates are willing and able to participate in for as long as possible.

9.
Trials ; 20(1): 537, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462310

RESUMO

BACKGROUND: Immunologic derangement may be the critical pathophysiologic mechanism in sepsis, and immunotherapy might be a potential new treatment. Si-ni-tang (SNT), an ancient Chinese herbal formula documented in Shanghan Lun, has been used for treating severe sepsis for thousands of years. Research shows that it may have a therapeutic benefit for sepsis. This study will evaluate the feasibility of testing the effects of SNT on immune function in sepsis patients. METHODS/DESIGN: This is a pilot randomized controlled study. Eligible sepsis patients admitted to our medical intensive care unit will be randomly allocated to the control group or the SNT group. Both groups will receive standard therapy according to the recommendations of the Surviving Sepsis Campaign. In addition, the SNT group will receive SNT (150 mL per day for 3 days) orally or by gastric tube, while the control group will receive 150 mL of normal saline. The primary outcome is to assess the feasibility of this treatment. The secondary outcomes include: (1) immune function measured by monocyte human leukocyte antigen-DR (mHLA-DR) expression, procalcitonin, and the ratio of CD4+ to CD8+ T lymphocytes and (2) other clinical data, such as the 28-day all-cause mortality, Sequential Organ Failure Assessment (SOFA) scores, Acute Physiology and Chronic Health Evaluation (APACHE) II scores, both of the latter on days 0 and 3. DISCUSSION: This study aims to evaluate the feasibility of testing the efficacy of SNT for treating sepsis when used as an adjunctive treatment with the standard therapy recommended by the Surviving Sepsis Campaign. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02777606 . Registered on 22 June 2016. Retrospectively registered. https://clinicaltrials.gov/.

10.
Sci Adv ; 5(8): eaax1396, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31453338

RESUMO

Atmospheric vapor pressure deficit (VPD) is a critical variable in determining plant photosynthesis. Synthesis of four global climate datasets reveals a sharp increase of VPD after the late 1990s. In response, the vegetation greening trend indicated by a satellite-derived vegetation index (GIMMS3g), which was evident before the late 1990s, was subsequently stalled or reversed. Terrestrial gross primary production derived from two satellite-based models (revised EC-LUE and MODIS) exhibits persistent and widespread decreases after the late 1990s due to increased VPD, which offset the positive CO2 fertilization effect. Six Earth system models have consistently projected continuous increases of VPD throughout the current century. Our results highlight that the impacts of VPD on vegetation growth should be adequately considered to assess ecosystem responses to future climate conditions.

11.
Toxins (Basel) ; 11(9)2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461921

RESUMO

Bacillus thuringiensis insecticidal proteins (Bt toxins) have been widely used in crops for agricultural pest management and to reduce the use of chemical insecticides. Here, we have engineered Bt toxin Cry2Ab30 and bioconjugated it with 4"-O-succinyl avermectin (AVM) to synthesize Cry2Ab-AVM bioconjugate. It was found that Cry2Ab-AVM showed higher insecticidal activity against Plutella xylostella, up to 154.4 times compared to Cry2Ab30. The binding results showed that Cry2Ab-AVM binds to the cadherin-like binding protein fragments, the 10th and 11th cadherin repeat domains in the P. xylostella cadherin (PxCR10-11), with a much higher affinity (dissociation equilibrium constant KD = 3.44 nM) than Cry2Ab30 (KD = 28.7 nM). Molecular docking suggested that the macrolide lactone group of Cry2Ab-AVM ligand docking into the PxCR10-11 is a potential mechanism to enhance the binding affinity of Cry2Ab-AVM to PxCR10-11. These findings offer scope for the engineering of Bt toxins by bioconjugation for improved pest management.

12.
Haematologica ; 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467124

RESUMO

Hematopoiesis is a finely regulated process in vertebrates under both homeostatic and stress conditions. By whole exome sequencing we have studied the genomics of acute lymphoid leukemia patients who needed multiple red blood cell transfusions after intensive chemotherapies. ARHGEF12, encoding a RhoA guanine nucleotide exchange factor, was found associated with chemotherapy-induced anemia by genome-wide association study analyses. A single nucleotide polymorphism (SNP) of ARHGEF12 located in an intron predicted to be a GATA1 binding site, rs10892563, is significantly associated with patients who need red blood cell transfusion (P=3.469E-03, odds ratio 5.864). A luciferase reporter assay revealed that this SNP impairs GATA1 mediated trans-regulation of ARHGEF12, and quantitative PCR studies confirmed that the homozygotes status is associated with ~61% reduction of ARHGEF12 expression (P=0.0088). Consequently, erythropoiesis was affected at the pro-erythroblast phase in the patients. A role of ARHGEF12 and its homologs in erythroid differentiation was confirmed in human K562 cells, mouse 32D cells and primary murine bone marrow cells. We further demonstrated in zebrafish by morpholino-mediated knockdown and CRISPR/Cas9-mediated knockout of arhgef12 that its reduction resulted in erythropoiesis defects. The p38 kinase pathway was affected by the ARHGEF12-RhoA signaling in K562 cells, and consistently, the arhgef12-rhoA-p38 pathway was also shown to be important for erythroid differentiation in zebrafish as active rhoA or p38 readily rescued the impaired erythropoiesis caused by arhgef12 knocking down. Finally, ARHGEF12 mediated p38 activity also appeared to be involved in phenotypes of patients of the rs10892563 homozygous genotype. Our findings present a novel SNP of ARHGEF12 that may involve ARHGEF12-RhoA-p38 signaling in erythroid regeneration in acute lymphoblastic leukemia patients after chemotherapy.

13.
J Environ Manage ; 248: 109310, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31376615

RESUMO

Microbial fuel cell (MFC) was compared to conventional biological techniques for decolorization of anthraquinone dye, reactive blue 19 (RB19) with simultaneous electricity generation. With 50 mg/L of RB19 in the anode chamber as a fuel, the MFC achieved 89% decolorization efficiency of RB19 within 48 h, compared with 51 and 55% decolorization efficiency achieved by aerobic and anaerobic techniques, respectively. The cyclic voltammetry results showed that RB19 could promote the electron transfer and redox reaction on the surface of anode. The RB19 decolorization process can be described by first-order kinetics, and the decolorization rate decreased with the increase of RB19 concentration. The high-throughput 16S rRNA sequencing analysis indicated significant microbial community shift in the MFC. At phylum level, the majority of sequences belong to Proteobacteria, accounting from 23 to 84% of the total reads in each bacterium community. At genus level, the MFC contained two types of microorganisms in general such as electrochemically active and decolorization bacteria. Overall, MFC is an effective method for anthraquinone dye treatment with simultaneous energy recovery. The 16S rRNA revealed that there were two major functioning microbial communities in the MFC such as electricity-producing and RB19-degrading bacteria which synergistically worked on RB19 degradation.

14.
Int J Mol Sci ; 20(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370253

RESUMO

Low-energy electrons (LEEs) of energies ≤30 eV are generated in large quantities by ionizing radiation. These electrons can damage DNA; particularly, they can induce the more detrimental clustered lesions in cells. This type of lesions, which are responsible for a large portion of the genotoxic stress generated by ionizing radiation, is described in the Introduction. The reactions initiated by the collisions of 0.5-30 eV electrons with oligonucleotides, duplex DNA, and DNA bound to chemotherapeutic platinum drugs are explained and reviewed in the subsequent sections. The experimental methods of LEE irradiation and DNA damage analysis are described with an emphasis on the detection of cluster lesions, which are considerably enhanced in DNA-Pt-drug complexes. Based on the energy dependence of damage yields and cross-sections, a mechanism responsible for the clustered lesions can be attributed to the capture of a single electron by the electron affinity of an excited state of a base, leading to the formation of transient anions at 6 and 10 eV. The initial capture is followed by electronic excitation of the base and dissociative attachment-at other DNA sites-of the electron reemitted from the temporary base anion. The mechanism is expected to be universal in the cellular environment and plays an important role in the formation of clustered lesions.

15.
Methods Mol Biol ; 2011: 547-571, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31273721

RESUMO

Tourette syndrome (TS) is a complex disorder characterized by repetitive, sudden, and involuntary movements or vocalizations, called tics. Tics usually appear in childhood, and their severity varies over time. In addition to frequent tics, people with TS are at risk for associated problems including attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety, depression, and problems with sleep. TS occurs in most populations and ethnic groups worldwide, and it is more common in males than in females. Previous family and twin studies have shown that the majority of cases of TS are inherited. TS was previously thought to have an autosomal dominant pattern of inheritance. However, several decades of research have shown that this is unlikely the case. Instead, TS most likely results from a variety of genetic and environmental factors, not changes in a single gene. In the past decade, there has been a rapid development of innovative genetic technologies and methodologies, as well as significant progress in genetic studies of psychiatric disorders. In this review, we will briefly summarize previous genetic epidemiological studies of TS and related disorders. We will also review previous genetic studies based on genome-wide linkage analyses and candidate gene association studies to comment on problems of previous methodological and strategic issues. Our main purpose for this review will be to summarize the new genetic discoveries of TS based on novel genetic methods and strategies, such as genome-wide association studies (GWASs), whole exome sequencing (WES), and whole genome sequencing (WGS). We will also compare the new genetic discoveries of TS with other major psychiatric disorders in order to understand the current status of TS genetics and its relationship with other psychiatric disorders.

16.
Clin Rheumatol ; 2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31302858

RESUMO

OBJECTIVE: This retrospective study evaluates lung abnormalities on high-resolution CT (HRCT) and clarifies which abnormality can predict the progressive fibrosis of rheumatoid arthritis (RA)-associated interstitial lung disease (ILD). OBJECTS AND METHODS: We identified 1096 RA patients, and enrolled 213 patients with a diagnosis of RA-ILD who underwent serial chest HRCT. Clinical data of the patients were obtained. The presence, extent, and distribution of lung abnormalities were assessed on CT scans. Logistic regression analysis was used to determine positive indicators with predictive value for progressive fibrosis, and 2 × 2 contingency tables were constructed to assess their diagnostic efficiency. RESULT: Of 213 RA-ILD patients, 106 (49.8%) were diagnosed as progressive fibrosis. The rates of advanced age, male, smoking history, shortness of breath, and anti-CCP antibody high titer positive were higher, and RA duration was shorter in progressive fibrosis patients. Reticular pattern (RP), peribronchovascular interstitium (PBVI) thickening, interlobular septal thickening, and traction bronchiolectasis were more common in the progressive fibrosis group (84.9% vs 42.1%, P < 0.001; 79.3% vs 45.8%, P < 0.001; 74.5% vs 43.9%, P < 0.001; 67.0% vs 40.2%, P < 0.001; respectively). Lung abnormalities demonstrated subpleural predominance, and the subpleural RP and/or interlobular septal thickening had a wide distribution in the progressive fibrosis group (71.7% vs 14.0%, P < 0.001). The overall extent of lung abnormalities was more extensive in the progressive fibrosis group (18.4% vs 14.2%, P < 0.05). Logistic regression analysis showed that a wide distribution of subpleural RP and/or interlobular septal thickening (OR, 18.15) and PBVI thickening (OR, 4.98) were independent risk factors predictive of progressive fibrosis. For the combination of these two CT abnormalities, sensitivity was 63.2%, specificity was 92.5%, positive likelihood ratio was 8.5, and negative likelihood ratio was 0.4 in predicting progressive fibrosis. CONCLUSIONS: A wide distribution of subpleural RP and/or interlobular septal thickening and PBVI thickening on HRCT appear predictive of progressive fibrosis in RA-ILD. The combined evaluation of these two CT abnormalities has a good judgment value. Key Points • We designed this study to investigate the risk factors for progressive fibrosis in patients with RA-ILD. Factors including clinical, physiological, radiological and therapeutic variables were all included in the data analysis. • Our results showed HRCT abnormalities, rather than other parameters, appeared predictive of progressive fibrosis in RA-ILD. • The methods and results of image evaluation in this article would provide reference to rheumatologists in identifying early stage of progressive fibrosis which helps to improve poor prognosis of RA-ILD.

17.
J Mol Neurosci ; 2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31302825

RESUMO

Methylenetetrahydrofolate reductase (MTHFR) polymorphism may increase the risk of schizophrenia in adults and aggravate related symptoms, while it is unknown whether similar risk applies in children with schizophrenia. While average onset age of schizophrenia is between the ages of 15 and 25, there are no studies on the relationship between MTHFR polymorphism and childhood-onset schizophrenia (COS). Here, we aimed to explore the risk of MTHFR polymorphism in children and examine the effects of MTHFR polymorphism on disease onset and clinical features in the COS patients. Pediatric patients with schizophrenia (n = 97) as well as age- and sex-matched controls (n = 92) were enrolled from the pediatric department. We evaluated clinical features including disease onset age, duration, Positive and Negative Syndrome Scale (PANSS), Personal and Social Performance Scale (PSP), and Clinical Global Impression (CGI). The three major MTHFR genotypes (G1793A, C677T, and A1298C) were examined in all subjects and the association between MTHFR polymorphism and clinical features of schizophrenia was analyzed. The G1793A polymorphism and the total number of MTHFR risk alleles were associated with an increased risk of schizophrenia in children. The A1298C polymorphism contributed to prolong the duration time of schizophrenia. Inconsistent with expectations, no significant associations were found between MTHFR C677T polymorphism and schizophrenia in children. Both G1793A and multi-site MTHFR polymorphisms are associated with an increased risk of schizophrenia in children, while A1298C polymorphism contributes to prolonged disease duration. While C677T is known to play major roles in the risk of adult schizophrenia, our finding for the first time suggests an age-specific association between MTHFR polymorphisms and schizophrenia.

18.
Nat Commun ; 10(1): 3190, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31320627

RESUMO

Brain metastases (BM) of colorectal cancer (CRC) are rare but lethal, and an understanding of their genomic landscape is lacking. We conduct an analysis of whole-exome sequencing (WES) and whole-genome sequencing (WGS) data on 19 trios of patient-matched BMs, primary CRC tumors, and adjacent normal tissue. Compared with primary CRC, BM exhibits elevated mutational signatures of homologous recombination deficiency (HRD) and mismatch repair deficiency (MMRD). Further analysis reveals two DNA damage response (DDR) signatures could emerge early and are enhanced in BM tissues but are eliminated eventually in matched primary CRC tissues. BM-specific mutations in DDR genes and elevated microsatellite instability (MSI) levels support the importance of DDR in the brain metastasis of CRC. We also identify BM-related genes (e.g., SCN7A, SCN5A, SCN2A, IKZF1, and PDZRN4) that carry frequent BM-specific mutations. These results provide a better understanding of the BM mutational landscape and insights into treatment.

19.
Med Eng Phys ; 70: 19-28, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31280927

RESUMO

Finite element (FE) models based on quantitative computed tomography (CT) images are better predictors of bone strength than conventional areal bone mineral density measurements. However, FE models require manual segmentation of the femur, which is not clinically applicable. This study developed a method for automated FE analyses from clinical CT images. Clinical in-vivo CT images of 13 elderly female subjects were collected to evaluate the method. Secondly, proximal cadaver femurs were harvested and imaged with clinical CT (N = 17). Of these femurs, 14 were imaged with µCT and three had earlier been tested experimentally in stance-loading, while collecting surface deformations with digital image correlation. Femurs were segmented from clinical CT images using an automated method, based on the segmentation tool Stradwin. The method automatically distinguishes trabecular and cortical bone, corrects partial volume effect and generates input for FE analysis. The manual and automatic segmentations agreed within about one voxel for in-vivo subjects (0.99 ±â€¯0.23 mm) and cadaver femurs (0.21 ±â€¯0.07 mm). The strains from the FE predictions closely matched with the experimentally measured strains (R2 = 0.89). The method can automatically generate meshes suitable for FE analysis. The method may bring us one step closer to enable clinical usage of patient-specific FE analyses.

20.
Cancer Med ; 8(10): 4906-4917, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31267686

RESUMO

INTRODUCTION: It remains unclear whether marital status could affect the breast cancer-caused special survival (BCSS) of patients with breast cancer. Therefore, we sought to explore the influence of demographic and pathological factors on prognosis of patients with breast cancer. MATERIALS AND METHODS: We selected patients meeting the eligibility criteria from the Surveillance, Epidemiology, and End Results (SEER) cancer registry program. We assessed the effect of marital status on overall survival (OS) and BCSS using Kaplan-Meier curve and multivariate Cox proportional hazards regression. RESULTS: Compared with divorced/separated/widowed (DSW) patients, the married (AHR 0.7483, 95% CI: 0.729-0.7682, P < 0.001) and single patients had better BCSS (AHR 0.9096, 95% CI: 0.8796-0.9406, P < 0.001). Married patients kept better prognosis among all age subgroups, while the better BCSS of single patients occurred only in groups older than 35 years. As for race and hormone receptor status (HRs), the better BCSS of single patients was only observed in white race (AHR 0.881, 95% CI: 0.8457-0.9177, P < 0.001) and patients with ER+/PR + status (AHR 0.8844, 95% CI: 0.8393-0.932, P < 0.001). CONCLUSION: Our findings demonstrated that married and single patients with breast cancer had better prognosis than their DSW counterparts. Age, race, and HRs could affect the correlation between marital status and BCSS.

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