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1.
Chaos ; 30(2): 023116, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32113230

RESUMO

As the potential for a treatment of Duchenne muscular dystrophy (DMD) grows, the need for methods for the early diagnosis of DMD becomes more and more important. Clinical experiences suggest that children with DMD will show some lack of motor ability in the early stage when compared with children at the same age, especially in balance and coordination abilities. Is it possible to quantify the coordination differences between DMD and typically developing (TD) children to achieve the goal of screening for DMD diseases? In this study, we introduced a Local Manifold Structure Mapping approach in phase space and extracted a novel index, relative coupling coefficient (RCC), from gait pattern signals, which were acquired by wearable accelerometers to evaluate the coordination of children with DMD during a walking task. Furthermore, we compared the RCC of 100 children with DMD and 100 TD children in four different age groups and verified the feasibility and reliability of the proposed indices to distinguish children with TD from DMD. T-test results show that, for all age groups, children of the same age with DMD and TD show significant differences in RCC (p < 0.001). Moreover, RCC comprehensively reflects that the coordination ability of DMD patients under walking tasks gradually decreases with age, which is consistent with clinical experience. As a functional biomarker extracted in the phase space of the gait data, the proposed coupling degree index RCC could sensitively distinguish between DMD and TD children at the same age and provide alternative insights and potentially valuable tools for the screening of DMD.

2.
J Mater Chem B ; 8(9): 1960-1970, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32067017

RESUMO

Recently emerged hemoperfusion absorbents, e.g. ion-exchange resin, activated carbon, and other porous materials, provide numerous novel possibilities to cure chronic liver failure (CLF) and renal failure (CRF). However, the limited adsorption performance and unsatisfactory blood compatibility significantly impede the development of the absorbents. Hence, designing safe and self-anticoagulant hemoperfusion absorbents with robust toxin clearance remains a considerable challenge. Here, brand new Kevlar-based composite gel beads for hemoperfusion are prepared by interface assembly based on π-π interaction. First, Kevlar nanofiber-graphene oxide (K-GO) beads are produced by liquid-liquid phase separation. Then, sodium p-styrenesulfonate (SS) is adsorbed onto the K-GO interface by π-π interaction and initiated to achieve the composite gel (K-GO/PSS) beads with an interfacial crosslinked structure. Such composite gel beads possess superior mechanical strength and self-anticoagulation capability, owing to the dual-network structure and heparin-mimicking gel structure, respectively. Furthermore, the K-GO/PSS beads show robust adsorption capacities for different kinds of toxins due to their strong charge and π-π interactions. A simulated hemoperfusion experiment in vitro demonstrates that the concentrations of the toxins in the blood can be restored to normal values within 30 minutes. In general, we envision that such composite gel beads will provide new strategies for future clinical CLF and CRF treatments.

3.
J Ultrasound Med ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32064662

RESUMO

OBJECTIVES: Super-resolution ultrasound (SRUS) has become a tool for in vivo microvascular imaging. Most of the SRUS methods are based on microbubble localization: namely, ultrasound localization microscopy (ULM). The aim of this study was to develop a nonlocalization SRUS method and verify its feasibility in microvascular imaging. METHODS: We introduce a new super-resolution strategy based on the postprocessing of contrast-enhanced ultrasound. The proposed method, which is termed ultrasound diffraction attenuation microscopy (UDAM), uses super-resolution radial fluctuations instead of microbubble localization to overcome acoustic diffraction limits. Biceps of Japanese long-ear white rabbits were adopted to validate its feasibility on muscle vascular imaging, using a clinical accessible ultrasound system at a frame rate of 30 Hz under a single bolus injection of SonoVue (Bracco SpA, Milan, Italy). The super-resolution image was compared with the maximum-intensity projection and ULM. RESULTS: The animal study illustrates that the proposed UDAM can obtain super-resolution microvascular images of rabbits' muscles under a single bolus injection of SonoVue with a 150-second contrast-enhanced ultrasound video. Both ULM and UDAM can achieve a very similar vascular structure with the maximum-intensity projection but much higher spatial resolution. The measurement of 1-dimensional signals shows that UDAM can distinguish the subwavelength structures and substantial reduce the full width at half-maximum of microvessels. CONCLUSIONS: We conclude UDAM provides a noninvasive tool for in vivo super-resolution microvascular imaging.

4.
Med Sci Monit ; 26: e918452, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31929498

RESUMO

BACKGROUND The diagnosis of thyroid cancer and distinguishing benign from malignant thyroid nodules by junior radiologists can be challenging. This study aimed to develop a computer-aided diagnosis (CAD) system based on the Thyroid Imaging Reporting and Data System (TI-RADS) to distinguish benign from malignant thyroid nodules by analyzing ultrasound images to improve the diagnostic performance of junior radiologists. MATERIAL AND METHODS A modified TI-RADS based on a convolutional neural network (CNN) was used to develop the CAD system. This retrospective study reviewed 789 thyroid nodules from 695 patients and included radiologists with different diagnostic experience. Five study groups included the CAD group, the junior radiologist group, the intermediate-level radiologist group, the senior radiologist group, and the group in which the junior radiologist used the CAD system. The ultrasound findings were reviewed and compared with the histopathology diagnosis. RESULTS The CAD system for the diagnosis of thyroid cancer showed an accuracy of 80.35%, a sensitivity of 80.64%, a specificity of 80.13%, a positive predictive value (PPV) of 76.02%, a negative predictive value (NPV) of 84.12%, and an area under the receiver operating characteristic (ROC) curve (AUC) of 0.87. The accuracy of the junior radiologists in diagnosing thyroid cancer using CAD was similar to that of intermediate-level radiologists (79.21% vs. 77.57%; P=0.427). CONCLUSIONS The use of ultrasound CAD based on the TI-RADS showed potential for distinguishing between benign and malignant thyroid nodules and improved the diagnostic performance of junior radiologists.

5.
Biomacromolecules ; 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31955566

RESUMO

Current therapy for liver failure and concomitant hyperbilirubinemia faces the challenge of poor hemocompatibility and bleeding risks associated with the anticoagulant injection. Herein, heparin-mimetic biomacromolecule (HepMBm) with a similar degree of sulfation and anticoagulant properties to heparin was synthesized by imitating the structure of natural biomacromolecule heparin. Then HepMBm was used to prepare nanocomposite spheres based on reduced graphene oxide (rGO). The formation of a dual-network structure in the spheres endowed the spheres with improved dimensional stability. The proposed spheres exhibited outstanding blood compatibilities and excellent self-anticoagulant properties. The bilirubin adsorption experiments and whole blood bilirubin removal assay indicated that the spheres exhibited high bilirubin removal capability from whole blood (The removal ratio was 99.69%.). The spheres open new routes for a therapeutic strategy without a plasma separation system and heparin pump, which may be a step toward a lightweight wearable artificial liver.

6.
Eur J Surg Oncol ; 46(4 Pt A): 600-606, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31973925

RESUMO

OBJECTIVE: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is a standard treatment for pseudomyxoma peritonei (PMP) recommended by Peritoneal Surface Oncology Group International (PSOGI). The study is to analyze the incidence of perioperative serious adverse events (SAEs) of CRS + HIPEC to treat PMP patients, and identify the risk factors, for guiding the prevention of SAEs. METHODS: This is a retrospective study on the PMP database established at our center. The clinicopathological features, treatment details and SAEs information on the PMP patients are systematically established in this database. The incidence, organ system distribution and severity of perioperative SAEs are analyzed. Univariate and multivariate analyses are performed to identify the independent risk factors. RESULTS: Among the 272 CRS + HIPEC procedures for 254 PMP patients, there are 93 (34.2%) SAEs. Six systems are involved in the SAEs, including infections (9.6%), digestive system (8.1%), respiratory system (6.3%), cardiovascular system (5.5%), hematological system (2.9%), and urinary system (1.5%), in terms of frequency. In terms of severity, the majority is grade III SAEs (27.9%), followed by grade IV SAEs (4.8%) and grade V SAEs (1.5%). Univariate analysis reveals 4 risk factors for perioperative SAEs: HIPEC regimens (P = 0.020), PCI (P = 0.025), intraoperative red blood cell transfusion volume (P = 0.004), and intraoperative blood loss volume (P = 0.002). Multivariate and logistic regression model analysis identifies only one independent risk factor for perioperative SAEs: intraoperative blood loss volume (P = 0.001, OR = 0.344, 95%CI: 0.182-0.649). CONCLUSIONS: PMP patients treated by CRS + HIPEC at experienced centers could have acceptable safety. Improving the surgical techniques and developing the integrated hemostasis techniques are essential to reduce intraoperative blood loss and decrease SAEs rate.

7.
Cytometry A ; 97(1): 70-77, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31411813

RESUMO

High incidence and mortality rates for non-small-cell lung cancer (NSCLC) lead to low survival rates. Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) are commonly first prescribed for NSCLC patients with EGFR mutations. However, most patients with sensitizing EGFR mutations become resistant to EGFR-TKI after 9-13 months treatment. Yiqi Chutan Tang (YQCT) has been prescribed as a treatment to this issue for over 20 years. In this report, high-performance liquid chromatography (HPLC) analysis, flow cytometry, western blot analysis, and functional annotation analysis were applied to uncover the molecular mechanisms of YQCT. Our results show the application of YQCT reduces gefitinib-induced drug resistance, induces slight cell cycle arrest, enhances gefitinib-induced apoptosis, and activates the autophagy. These results indicate that at the molecular level YQCT can reduce drug resistance and improve anti-cancer effects when associated with gefitinib, which could be a result of enhancement of apoptosis and autophagy in the EGFR-TKI resistant cells of NSCLC. This research provides a new treatment strategy for patients with EGFR-TKI resistance in NSCLC. © 2019 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.

8.
Cancer Med ; 9(3): 1104-1114, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31814323

RESUMO

BACKGROUND: Pseudomyxoma peritonei (PMP) is an indolent malignancy and insensitive to systemic chemotherapy. The authors established patient-derived xenograft (PDX) model of PMP, and evaluated the efficacy and toxicity of intraperitoneal (i.p.) administration of 5-fluorouracil (5-FU) in this model. METHODS: Human PMP sample was collected to establish subcutaneous (s.c.) and i.p. MODEL: In vivo study of i.p. injection of 5-FU was performed in i.p. model, with experimental peritoneal cancer index (ePCI) score and pathological examinations for evaluating the efficacy and toxicity. RESULTS: Both s.c. and i.p. models were constructed. The average passage interval of s.c. model was 44.2 ± 5.2 days, and the i.p. model was characterized by disseminated solid tumor nodules in abdominal-pelvic cavity. Both models were diagnosed as peritoneal mucinous carcinomatosis with signet ring cells (PMCA-S). Immunohistochemical characteristics was similar to human. GNAS mutation was detected in both model and patient. In the in vivo study, average ePCI of treatment group was lower than control and vehicle group (P = .004). Histopathology revealed obvious tumor necrosis in treatment group, and decreased Ki67 positive rate (P = .010). In toxicity study, 5-FU significantly influenced body weight (P = .010) and 1 animal from treatment group died on day 14. Congestive splenomegaly was observed (88.9%). Hepatotoxicity presented as acidophilic body (55.6%), cholestasis (100%), bile canaliculus hyperplasia and obstruction (22.2%), and lymphocyte accumulation (77.8%). CONCLUSIONS: PDX model of PMCA-S was established successfully, and i.p. 5-FU could inhibit tumor proliferation and progression, with decreased Ki67 positive rate and ePCI score. Hepatotoxicity was the main side effect.

9.
Mater Sci Eng C Mater Biol Appl ; 107: 110311, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761197

RESUMO

In this study, a small-diameter, double-layered eggshell membrane/thermoplastic polyurethane (ESM/TPU) vascular graft with a wavy structure was developed. The avian eggshell membrane, a fibrous structure similar to the extracellular matrix (ECM), has the potential to yield rapid endothelialization in vitro. The dopamine and heparin modification of the ESM surface not only promoted human umbilical vein endothelial cell (HUVEC) proliferation via cytocompatibility assessment, but also improved its anticoagulation properties as verified in platelet adhesion tests. The biomimetic mechanical properties of the vascular graft were provided by the elastic TPU fibers via electrospinning using a wavy cross-section rotating collector. The advantage of combining these two materials is to make use of the bioactivity of ESM as the internal membrane and the tunable mechanical properties of TPU as the external layer. The circumferentially wavy structure of the vascular graft produced a toe region in the non-linear section of the stress-strain curve similar to that of natural blood vessels. The ESM/TPU graft's circumferential ultimate strength was 2.57 MPa, its strain was 339% mm/mm, and its toe region was found to be around 20% mm/mm. Cyclical tension tests showed that the vascular graft could maintain good mechanical properties and showed no structural damage under repeated extension tests.

10.
Magn Reson Imaging ; 65: 67-74, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31654738

RESUMO

Atheroembolic renal disease (AERD) is the major cause of renal insufficiency in the elderly, and particularly, the diagnose of AERD is often delayed and even missed due to its nonspecific presentation and the sudden occurrence of an embolic event. To investigate the feasibility of the view-shared compressed sensing (VCS) based dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) in the assessment of AERD in animal models. The reproducibility of VCS DCE-MRI based glomerular filtration rate (GFR) estimation was first evaluated using the three healthy rabbits. Animal models of unilateral AERD were then conducted. All the rabbits underwent VCS DCE-MRI and the GFR maps were estimated by a commonly used cortical-compartment model. The whole kidney and suspicious lesion region GFR values of embolized kidneys were then compared with the corresponding values of normal kidneys. Finally, the suspicious lesion regions were confirmed by the corresponding renal specimens and histological findings. The reproducibility of GFR measurements was analyzed using the coefficient of variation and Bland-Altman analysis. The GFR values of normal and embolized kidneys were compared using the Student t-test. Contrast-enhanced images with sufficient diagnostic quality and reduced motion artifacts are obtained at a temporal resolution of 2.5 s. The Bland-Altman plot indicated close agreement between the GFR values estimated from between-day scans in healthy rabbits. Besides, there existed significant differences between the pixel-wise GFR values of normal and AERD kidneys in region-based comparison(P < 0.0001). The suspicious lesions are consistent well with the renal specimen and histological findings. The preliminary animal study verified the feasibility of VCS DCE-MRI for renal function evaluation, and the strategy could potentially provide a valuable tool to identify AERD.

11.
Front Neurosci ; 13: 1075, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31680815

RESUMO

Foot-sole somatosensory impairment is a main contributor to balance decline and falls in aging and disease. The cortical networks involved in walking-related foot sole somatosensation, however, remain poorly understood. We thus created and tested a novel MRI-compatible device to enable study of the cortical response to pressure stimuli applied to the foot sole that mimic those stimuli experienced when walking. The device consists of a dual-drive stimulator equipped with two pneumatic cylinders, which are separately programed to apply pressure waveforms to the entire foot sole. In a sample of nine healthy younger adults, the pressure curve applied to the foot sole closely correlated with that experienced during over ground walking (r = 0.811 ± 0.043, P < 0.01). MRI compatibility testing indicated that the device has no or negligible impact on MR image quality. Gradient-recalled echo-planar images of nine healthy young adults using a block-designed 3.5-min walking-related stimulation revealed significant activation within the supplementary motor area, supramarginal gyrus, paracingulate gyri, insula, precentral gyrus, middle temporal gyrus, and hippocampus (uncorrected P < 0.001, k ≥ 10). Together, these results indicate that this stimulation system is MRI-compatible and capable of mimicking walking-related pressure waveforms on foot sole. It may thus be used as a research tool to identify cortical targets for interventions (e.g., non-invasive brain stimulation) aimed at enhancing this important source of input to the locomotor control system.

12.
J Healthc Eng ; 2019: 7294582, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31737241

RESUMO

To overcome the two-class imbalanced problem existing in the diagnosis of breast cancer, a hybrid of K-means and Boosted C5.0 (K-Boosted C5.0) is proposed which is based on undersampling. K-means is utilized to select the informative samples near the boundary. During the training phase, the K-means algorithm clusters the majority and minority instances and selects a similar number of instances from each cluster. Boosted C5.0 is then used as the classifier. As there is one different instance selection factor via clustering that encourages the diversity of the training subspace in K-Boosted C5.0, it would be a great advantage to get better performance. To test the performance of the new hybrid classifier, it is implemented on 12 small-scale and 2 large-scale datasets, which are the often used datasets in class imbalanced learning. The extensive experimental results show that our proposed hybrid method outperforms most of the competitive algorithms in terms of Matthews' correlation coefficient (MCC) and accuracy indices. It can be a good alternative to the well-known machine learning methods.

13.
Int J Biol Macromol ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31783078

RESUMO

Adsorbents are usually used to remove uremic toxins for blood purification. However, the removal of urea is still an intractable problem, since no effective material has been found for urea removal by physical adsorption. Here, urease immobilized graphene oxide core@shell heparin-mimicking polymer (U-GO-HMP) beads were designed, which exhibited good urea removal ability with a removal amount of about 635 mg/g and a removal ratio of about 80% from urea solution. In addition, urea could be removed from collected dialysate and the removal ratio could reach 60% within 480 min. Beyond that, the U-GO-HMP beads also showed good reusability with sustainable relative activity after 5 cycles. Furthermore, the U-GO-HMP beads exhibited good blood compatibility with low hemolysis ratio, suppressed complement activation and contact activation, as well as increased clotting times. It is worthy believing that the U-GO-HMP beads may have great potential in the field of blood purification for urea removal.

14.
Sci China Life Sci ; 62(10): 1396-1399, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31573054
15.
World J Plast Surg ; 8(3): 324-330, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31620334

RESUMO

BACKGROUND: Ear reconstruction is one of the most challenging surgeries faced by reconstructive surgeons because of its complex three-dimensional structure. Various surgical methods and materials have been used over the years. The process of microtia reconstruction using tissue expander is performed in three stages of first that is implantation of tissue expander, second stage involves framework fabrication using autologous costal cartilage and implantation in the pocket and third stage involves tragus and concha reconstruction. METHODS: Totally 180 cases of microtia reconstruction using tissue expander and autologous costal cartilage over 2 years were enrolled, while two age groups were compared regarding operative time, tissue expansion, number of autologous costal cartilage harvested and complications during and after reconstruction. RESULTS: The overall complication in microtia reconstruction was 25%. No major difference was found between complication rates among the 2 age groups. Similarly, no significant difference was found between two groups in term of surgical time and tissue expansion. The major difference was found in number of costal cartilage harvested for the framework fabrication among the two groups. CONCLUSION: Microtia reconstruction using tissue expander and autologous costal cartilage is a standard method of ear reconstruction with good satisfaction rate for surgeons and patients. Although the complication rate was high in our study, most of the cases were managed with acceptable results. Therefore, a standard protocol should be developed regarding the timing of the surgery for microtia reconstruction, considering pre-operative radiological analysis of the costal cartilage development along with age and weight of the patient.

16.
Circ Res ; 125(12): 1087-1102, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31625810

RESUMO

RATIONALE: A hallmark of chronic inflammatory disorders is persistence of proinflammatory macrophages in diseased tissues. In atherosclerosis, this is associated with dyslipidemia and oxidative stress, but mechanisms linking these phenomena to macrophage activation remain incompletely understood. OBJECTIVE: To investigate mechanisms linking dyslipidemia, oxidative stress, and macrophage activation through modulation of immunometabolism and to explore therapeutic potential targeting specific metabolic pathways. METHODS AND RESULTS: Using a combination of biochemical, immunologic, and ex vivo cell metabolic studies, we report that CD36 mediates a mitochondrial metabolic switch from oxidative phosphorylation to superoxide production in response to its ligand, oxidized LDL (low-density lipoprotein). Mitochondrial-specific inhibition of superoxide inhibited oxidized LDL-induced NF-κB (nuclear factor-κB) activation and inflammatory cytokine generation. RNA sequencing, flow cytometry, 3H-labeled palmitic acid uptake, lipidomic analysis, confocal and electron microscopy imaging, and functional energetics revealed that oxidized LDL upregulated effectors of long-chain fatty acid uptake and mitochondrial import, while downregulating fatty acid oxidation and inhibiting ATP5A (ATP synthase F1 subunit alpha)-an electron transport chain component. The combined effect is long-chain fatty acid accumulation, alteration of mitochondrial structure and function, repurposing of the electron transport chain to superoxide production, and NF-κB activation. Apoe null mice challenged with high-fat diet showed similar metabolic changes in circulating Ly6C+ monocytes and peritoneal macrophages, along with increased CD36 expression. Moreover, mitochondrial reactive oxygen species were positively correlated with CD36 expression in aortic lesional macrophages. CONCLUSIONS: These findings reveal that oxidized LDL/CD36 signaling in macrophages links dysregulated fatty acid metabolism to oxidative stress from the mitochondria, which drives chronic inflammation. Thus, targeting to CD36 and its downstream effectors may serve as potential new strategies against chronic inflammatory diseases such as atherosclerosis.

17.
Arch Gynecol Obstet ; 300(6): 1729-1739, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31646386

RESUMO

PURPOSE: This study aimed to identify the existence of uterine micro-peristalsis (UMP) by dynamic ultrasound features and evaluate the feasibility of UMP as a tool to distinguish pregnant and non-pregnant infertility patients undergoing in vitro fertilization-embryo transfer (IVF-ET), using clinical pregnancy results as a benchmark. METHODS: Fifty-one women, including 29 pregnant and 22 non-pregnant patients were recruited. Also, ultrasound videos were collected before embryo transfer. First of all, undiscoverable uterine micro-peristalsis was magnified by video magnification. Then, the dynamic features of UMP were characterized by a novel index termed histogram entropy based on the micro-peristalsis feature selection by entropy weight (HEMEW), which was generated by combining frame difference and volume local phase quantization. Finally, a comparative experiment of HEMEW between non-pregnant and pregnant patients, logistic regression analysis for HEMEW and other independent clinical characteristics, and receiver operating characteristic (ROC) analysis were performed. RESULTS: The magnified uterine video clearly exhibited UMP, which was invisible in the original ultrasound video. Further, there existed a significant difference in HEMEW between pregnant patients and non-pregnant patients after micro-motion magnification (p = 0.003, n = 51). The logistic regression result showed that HEMEW (p = 0.006) was significantly associated with clinical pregnancy outcome, while other independent variables had no significant effect on it. The ROC performance of HEMEW was 72.6% accuracy (AUC = 0.774, 95% CI: 0.644-0.905). CONCLUSIONS: The proposed micro-motion magnification and characterization strategy identified the existences of uterine micro-peristalsis, and verified that UMP has the feasibility to distinguish the outcomes of IVF-ET.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31652627

RESUMO

Rare earth elements (REEs), known as "industrial vitamins", are widely used in medical treatment, industry, agriculture, etc. However, with the increasing demand for REEs, excess REEs, such as gadolinium (Gd), are considered micropollutants in the environment. In this paper, the distributions of dissolved REEs were analyzed in three small streams, in order to determine the extent and occurrence of Gd anomalies. The shale-normalized REE patterns in the three streams were less smooth with heavy REEs higher than light REEs, for a weak reaction of the heavy REE complexes. A negative Ce (cerium) anomaly and positive samarium (Sm) and europium (Eu) anomalies were observed in the three streams and the negative Ce anomaly was affected by the pH of the alkaline rivers. However, a positive Gd anomaly was found in only a typical urban small stream, Jinzhong. With a population of approximately 60,000, Jinzhong runs by a hospital and through wastewater treatment plants (WWTPs). The concentrations of Gd in Jinzhong ranged from 1.54 to 86.65 ng/L with high anthropogenic Gd proportions (63.64%-98.07%). Anthropogenic Gd showed significant seasonal variations and distinct spatial disparities from upstream to downstream, and it was associated with certain ions such as Cl-. Anthropogenic Gd could be attributed to gadopentetic acid (Gd-DTPA), which is used in magnetic resonance imaging (MRI) in hospitals. This type of Gd was shown to be correlated with municipal wastewater. Due to the high stability and low particulate reactivity in water, anthropogenic Gd has great potential to serve as a tracer to prove the presence of medical wastewater.


Assuntos
Metais Terras Raras/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Rios/química , Águas Residuárias
19.
Cell Mol Life Sci ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492966

RESUMO

Cullin ring-finger ubiquitin ligase 4 (CRL4) has multiple functions in the maintenance of oocyte survival and meiotic cell cycle progression. DCAF13, a novel CRL4 adaptor, is essential for oocyte development. But the mechanisms by which CRL4-DCAF13 supports meiotic maturation remained unclear. In this study, we demonstrated that DCAF13 stimulates the meiotic resumption-coupled activation of protein synthesis in oocytes, partially by maintaining the activity of PI3K signaling pathway. CRL4-DCAF13 targets the polyubiquitination and degradation of PTEN, a lipid phosphatase that inhibits PI3K pathway as well as oocyte growth and maturation. Dcaf13 knockout in oocytes caused decreased CDK1 activity and impaired meiotic cell cycle progression and chromosome condensation defects. As a result, chromosomes fail to be aligned at the spindle equatorial plate, the spindle assembly checkpoint is activated, and most Dcaf13 null oocytes are arrested at the prometaphase I. The DCAF13-dependent PTEN degradation mechanism fits in as a missing link between CRL4 ubiquitin E3 ligase and PI3K pathway, both of which are crucial for translational activation during oocyte GV-MII transition.

20.
J Sports Sci ; 37(22): 2625-2630, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31379263

RESUMO

The dynamics of tremulous motion in the upper limb is complex. We aimed to explore the relationship between the complexity of upper limb tremor when aiming and aiming performance and the influences of physical load on the two outcomes. Fifteen modern pentathlon athletes were recruited and completed two 1000-m treadmill running and three 60-s standard aiming task trials: one at baseline and each of the other two immediately after each running. The time series of light spot trace on the target was measured using a high-speed camera. The complexity of this time series was quantified using multiscale entropy. The effective aiming rate was used to assess the aiming performance. We observed that participants with lower tremor complexity had lower effective aiming rate across three physical load conditions (r2 > 0.38, p < 0.01). Physical load decreased both tremor complexity (F = 4.8, p = 0.01) and effective aiming rate (F = 13.5, p < 0.0001), but no difference was observed after 1000-m running compared to that after 2000-m running. The per cent change of tremor complexity associated with the change of effective aiming rate (r2 = 0.55, p < 0.0001). This pilot study demonstrates that multiscale complexity of tremulous motion in the upper limb when aiming may serve as a novel marker to assess the physiologic system functionality when aiming.


Assuntos
Desempenho Atlético/fisiologia , Movimento/fisiologia , Esportes/fisiologia , Extremidade Superior/fisiologia , Adulto , Feminino , Armas de Fogo , Humanos , Masculino , Projetos Piloto , Corrida/fisiologia , Análise e Desempenho de Tarefas , Tremor/fisiopatologia , Suporte de Carga , Adulto Jovem
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