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1.
J Nanosci Nanotechnol ; 20(2): 692-700, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383064

RESUMO

Fluorescent bimetallic Au-Ag nanoclusters (Au-AgNCs) were found to exhibit oxidase-like activity and could catalyze the oxidation of 3,3',5,5' tetramethylbenzidine (TMB) to oxTMB. On the basis of this property, we assembled a fluorescent nanoplatform as a turn-on probe for sensing mercury (II) ions (Hg2+) through the inner-filter effect (IFE). Au-AgNCs and oxTMB were chosen as IFE absorber and fluorophore pair for the first time. In the absence of Hg2+, the Au-AgNCs absorption band well. Covered the fluorescence emission band of oxTMB, and as a result, the fluorescence of oxTMB was reduced. In the presence of Hg2+, Hg2+ was reduced to Hg0 by extra BSA in Au-AgNCs probe system and anchored on the surface of Au-AgNCs. The absorption intensity for Au-AgNCs then decreased at 418 nm, resulting in the recovery of fluorescence from oxTMB. The formed Au-Hg thin amalgam layer obviously enhanced the oxidase-like activity of Au-AgNCs as well as hindered the IFE activity between Au-AgNCs and oxTMB. Therefore, based on the Hg2+ stimulating oxidaselike properties of Au-AgNCs, a fluorometric assay for determination of Hg2+ was developed in this study. The proposed sensing strategy showed a linear range from 10 nM to 500 nM, with ultralow LOD of ~0.7 nM for Hg2+. Moreover, the detection probe system was stable over a wide pH range, making it able to be applied in complex sample systems. We have successfully demonstrated the detection of Hg2+ in tap water samples. The fluorescent assay reported here, for sensitive and selective determination of Hg2+, may find great application in multiple areas, such as environmental and pharmaceutical analysis.

2.
Vet Immunol Immunopathol ; 215: 109913, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31420069

RESUMO

The development of a rapid and efficient system to generate porcine monoclonal antibodies (mAbs) is an important step toward the discovery of critical neutralizing targets for designing rational vaccines against porcine viruses. In this study, we established a platform for producing porcine mAbs based on single cell technologies. First, we singled out an optimal donor from 507 pigs based on serum antibody neutralizing activity against porcine reproductive and respiratory syndrome virus (PRRSV). After identifying the contribution of IgG to the neutralizing activity, single CD45R+IgG+Ag+ B cells were sorted from peripheral blood mononuclear cells (PBMCs). Single B cell RT-PCR was performed using primers designed to cover the germline repertoire of the porcine VH/VL gene segments. Paired VH/VLs were cloned into a eukaryotic expression vector and transfected into 293T cells. We demonstrate that full-length porcine mAbs were produced, and antigen-specific mAbs were obtained after further validation. The approach reported in this study can be applied to generate porcine mAbs against any given antigen and may help with the screening of neutralizing antibodies against porcine pathogens.

3.
J Biomed Opt ; 24(8): 1-11, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31429215

RESUMO

X-ray luminescence computed tomography (XLCT) is an emerging hybrid imaging modality which has the potential for achieving both high sensitivity and spatial resolution simultaneously. For the narrow x-ray beam-based XLCT imaging, based on previous work, a spatial resolution of about double the x-ray beam size can be achieved using a translate/rotate scanning scheme, taking step sizes equal to the x-ray beam width. To break the current spatial resolution limit, we propose a scanning strategy achieved by reducing the scanning step size to be smaller than the x-ray beam size. We performed four sets of numerical simulations and a phantom experiment using cylindrical phantoms and have demonstrated that our proposed scanning method can greatly improve the XLCT-reconstructed image quality compared with the traditional scanning approach. In our simulations, by using a fixed x-ray beam size of 0.8 mm, we were able to successfully reconstruct six embedded targets as small as 0.5 mm in diameter and with the same edge-to-edge distances by using a scanning step as small as 0.2 mm which is a 1.6 times improvement in the spatial resolution compared with the traditional approach. Lastly, the phantom experiment further demonstrated the efficacy of our proposed method in improving the XLCT image quality, with all image quality metrics improving as the step size decreased.

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4.
Brain Res Bull ; 153: 15-23, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31400495

RESUMO

Recent animal studies on heterochronic parabiosis (a technique combining the blood circulation of two animals) have revealed that young blood has a powerful rejuvenating effect on brain aging. Circulating factors, especially growth differentiation factor 11 (GDF11) and C-C motif chemokine 11 (CCL11), may play a key role in this effect, which inspires hope for novel approaches to treating age-related cerebral diseases in humans, such as neurodegenerative and neurovascular diseases. Recently, attempts have begun to translate these astonishing and exciting findings from mice to humans and from bench to bedside. However, increasing reports have shown contradictory data, questioning the capacity of these circulating factors to reverse age-related brain dysfunction. In this review, we summarize the current research on the role of young blood, as well as the circulating factors GDF11 and CCL11, in the aging brain and age-related cerebral diseases. We highlight recent controversies, discuss related challenges and provide a future outlook.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31403937

RESUMO

BACKGROUND: IVD degeneration is a widespread problem all over the world, which a variety of inflammatory cytokines have been implicated in, while Sphingosine 1-phosphate (S1P) is an important lipid mediator that may play a role in IVD degeneration. OBJECTIVE: To study the expression and role of S1PRs in the intervertebal disc (IVD) degeneration to enhance understanding of disc degeneration. METHODS: Degenerated and normal IVD were harvested from patients through surgery. Expression of S1P receptor subtypes was evaluated using real-time PCR, immunohistochemistry, and western blotting. The effect of S1PR on inflammation induced by interleukin-1ß in nucleus pulposus (NP) cells was also assessed by real time PCR and western blotting. RESULTS: The nucleus pulposus mainly expressed the S1PR1/2/3, and the expression decreased in the severe degenerated nucleus pulposus cells. The ligand, S1P, inhibited the up-regulation of matrix metallopeptidase-3 (MMP-3) and ADAM metallopeptidase with thrombospondin type 1 motif 4 (ADAMTS4) induced by IL-1ß. CONCLUSIONS: The results show that an the expression of S1PRs in degenerative discs is down-regulated as degeneration, and S1P can inhibit the inflammation response induced by IL-1ß in NP cells, implicating that S1P/S1PR may contribute to IVD degeneration.

6.
Clin Neurol Neurosurg ; 183: 105377, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31279300

RESUMO

OBJECTIVES: To assess the feasibility of cement-augmented fenestrated pedicle screw for patients with spondylolisthesis with osteoporotic spine. PATIENTS AND METHODS: From January 2014 to March 2018, a retrospective study of 88 patients with spondylolisthesis and osteoporosis treated with minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using the conventional pedicle screw (CPS group, n = 52) and the fenestrated pedicle screw (FPS group, n = 36) was performed with a follow-up of 30 months (range, 10-58 months). Clinical outcomes, overall changes in slip degree, and interbody fusion rates were evaluated via questionnaires and radiographic parameters. RESULTS: The VAS, ODI and JOA scores at 3 months were significantly improved in both groups compared with the preoperative assessment (p < 0.001). No significant differences in scores were found between the two groups at any time. Imaging results at different time points revealed greater postoperative improvement in the Taillard index in the FPS group compared with the CPS group. No significant differences in the interbody fusion speed or rates were found between the two groups. In the FPS group, cement leakage occurred in 22 of 97 screws (22.7%), and symptomatic cement leakage was not found. CONCLUSION: MIS-TLIF combined with fenestrated pedicle screws provided greater reduction than did MIS-TLIF combined with conventional pedicle screws in terms of postoperative slip degree. And the application of fenestrated pedicle screw did not obstruct the interbody fusion. Overall, MIS-TLIF combined with the fenestrated pedicle screws is an effective and safe technique for the treatment of spondylolisthesis with osteoporotic spine.

7.
Am J Chin Med ; 47(5): 1043-1056, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31311299

RESUMO

Baicalein is a natural flavonoid with anti-oxidant activities protecting against ischemia/reperfusion (I/R) injury. Previous studies suggest that oxidative burst early after reperfusion accelerates cell death. We therefore investigated the critical therapeutic window of baicalein by examining the timing of baicalein treatment in relation to its oxidant modulating and cytoprotective effects. Using an established chick cardiomyocyte model of I/R, we administered baicalein at various time points after reperfusion and assessed cell viability and the profiles of reactive oxygen species (ROS), nitric oxide (NO), and Akt phosphorylation. Baicalein administered at the onset of reperfusion resulted in a concentration-dependent reduction of cell death (25 µM 48.2±1.9%, 50µM 43.8±1.5%, 100µM 36.6±2.1%, vs. I/R control 57.3±1.4%, all p<0.05). Baicalein (100µM) timely and effectively scavenged ROS burst and enhanced NO production in the early reperfusion phase. Cotreatment with NO synthase (NOS) inhibitor l-NAME (200µM) partially abrogated the cytoprotective effect. Baicalein (100µM) given after reperfusion lost protective effect in a time-dependent manner with cytoprotection completely lost if >60min. Even with only 15-min delay after reperfusion, the ROS scavenging effect was abolished and the NO enhancing effect markedly reduced. The phosphorylation of Akt, an upstream regulator of eNOS, also diminished as the delay lengthened. In conclusion, baicalein treatment after reperfusion confers cardioprotection in a concentration- and time-dependent manner. The critical therapeutic window lies in the early reperfusion phase, during which ROS scavenging and Akt-eNOS mediated NO signaling are most effective.

8.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(7): 801-806, 2019 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-31297995

RESUMO

Objective: To investigate the clinical results and complication prevention of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in the treatment of single-segment severe lumbar spinal stenosis (LSS). Methods: The clinical data of 112 patients with severe LSS treated with MIS-TLIF between January 2010 and January 2017 were retrospectively analyzed. There were 43 males and 69 females, aged 52-81 years, with an average age of 65.3 years. The disease duration ranged from 4 to 126 months, with an average of 10.5 months. Clinical manifestations: 104 cases of low back pain, 91 cases of nervous intermittent claudication of both lower limbs, 21 cases of unilateral nerve root pain and/or numbness, and 5 cases of cauda equina nerve injury. The 112 cases were all severe central spinal stenosis, including 32 cases with lateral recess stenosis, 20 cases with foramen stenosis, 9 cases with ossification of ligamentum flavum, 38 cases with disc herniation; 14 cases with two complications and 5 cases with three. Stenosis segment: L 3, 4 in 6 cases, L 4, 5 in 89 cases, and L 5, S 1 in 17 cases. Surgical methods included bilateral decompression through bilateral approach (60 cases), bilateral decompression through unilateral approach (15 cases), and unilateral decompression (37 cases). The operation time, intraoperative blood loss, visual analogue scale (VAS) score of low back pain and leg pain, Oswestry disability index (ODI) score, fusion rate, and surgical complications were recorded. At last follow-up, the lumbar fusion was evaluated by Bridwell method, grades Ⅰ and Ⅱ were expressed as fusion. Results: The operation time was 83-186 minutes (mean, 126.8 minutes), and the intraoperative blood loss was 65-630 mL (mean, 163.1 mL). All the 112 patients were followed up 25-49 months, with an average of 35.1 months. The VAS score of low back pain and leg pain and ODI score at each time point after operation were significantly improved when compared with preoperative scores ( P<0.05). There was no significant difference between the VAS score of low back pain and leg pain and ODI score at the other time points except 1 month after operation ( P<0.05). At last follow-up, 2 cases of cauda equina nerve injury recovered and 3 cases partially recovered. According to Bridwell classification criteria, 58 cases were grade Ⅰ, 47 cases were grade Ⅱ, and 7 cases were grade Ⅲ. The fusion rate was 93.8%. Perioperative complications included 5 cases of incision complications (superficial infection in 3 cases, hematoma formation in 2 cases), 19 cases of internal fixator complications (intraoperative end plate fracture in 8 cases, fusion cage sinking in 11 cases at last follow-up), and 15 cases of neurological complications (dural sac tear in 10 cases, transient neurological symptoms of lower extremities aggravated in 5 cases). Conclusion: MIS-TLIF treatment of single-level severe LSS can achieve good clinical results, while there is a risk of serious complications. Full understanding of the clinical and imaging features of the disease and reasonable and careful operation are helpful to control the occurrence of cauda equina nerve damage.

9.
ACS Appl Mater Interfaces ; 11(23): 20778-20787, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31117435

RESUMO

Although most metal-organic coordination materials are promising materials used as templates to develop highly efficient electrocatalysts via pyrolysis in situ, few studies have explored the use of these materials for direct catalysis of oxygen evolution reaction (OER). Herein, inspired by the natural synthesis and the inherent properties of metal-organic coordination materials, the FeNi-tannic acid coordination crystal was in situ grown on Ni foam ((FeNi)-Tan/NF) to directly catalyze the OER. It was found that (FeNi)-Tan/NF exhibited predominant OER activity, which required a low overpotential of 208 mV to reach a current density of 50 mA·cm-2 under a small Tafel slope of 33.5 mV·dec-1, and it possessed robust stability. Density functional theory (DFT) calculations demonstrated that the active site change from Ni in Ni-Tan to the Fe atom in (FeNi)-Tan may provide a more favorable OER catalytic route. This application of such polyphenol coordination materials is promising for stimulating the exploration of functional metal-organic coordination materials toward applications in the energy conversion field.

10.
Medicine (Baltimore) ; 98(19): e15422, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31083171

RESUMO

This study was designed to investigate the factors affecting the in-hospital delay of intravenous thrombolysis (IVT) for acute ischemic stroke (AIS).Two hundred and forty-eight consecutive AIS patients treated with intravenous administration of alteplase in Gansu Provincial Hospital from December 2014 to August 2018 were enrolled retrospectively in this study. According to door-to-needle (DTN) time, the patients were divided into either a delay group (DTN time > 60 minutes; n = 184) or a non-delay group (DTN time ≤60 minutes; n = 64). The baseline data, laboratory tests, onset-to-door (OTD) time, door-to-accepting time (DTA), door-to-imaging time (DTI), and decision-making time in both groups were recorded. Multivariate logistic analysis was performed to analyze the data.There were significant differences in previous history of cerebral ischemic attack, emergency system admission, education degree of decision makers, annual income, admission National Institutes of Health Stroke Scale (NIHSS), OTD time, DTA time, decision-making time between the 2 groups (all P < .05). Other baseline data and clinical features showed no significant difference between 2 groups (P > .05). Multivariate logistic regression analysis revealed that the risk of in-hospital delay was lower for the higher NIHSS score (OR = 0.775, 95% CI: 0.644-0.933, P = .007), the longer OTD time (OR = 0.963, 95% CI: 0.937-0.991, P = .010), the shorter decision-making time (OR = 1.224, 95% CI: 1.004-1.492, P = .045).This study suggested that NIHSS score, OTD time and decision-making time are the independent factors affecting the in-hospital delay of IVT for AIS.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Hospitalização , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica , Tempo para o Tratamento , Administração Intravenosa , Idoso , Isquemia Encefálica/epidemiologia , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/epidemiologia
11.
Cell Death Dis ; 10(5): 360, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043581

RESUMO

Transforming growth factor ß (TGF-ß) serves critical functions in brain injury, especially in cerebral ischemia; however, apart from its neuroprotective effects, its role in regulating neurogenesis is unclear. TGF-ß acts in different ways; the most important, canonical TGF-ß activity involves TGF-ß receptor I (TßRI) or the activin receptor-like kinase 5 (ALK5) signaling pathway. ALK5 signaling is a major determinant of adult neurogenesis. In our previous studies, growth arrest and DNA damage protein 45b (Gadd45b) mediated axonal plasticity after stroke. Here, we hypothesized that ALK5 signaling regulates neural plasticity and neurological function recovery after cerebral ischemia/reperfusion (I/R) via Gadd45b. First, ALK5 expression was significantly increased in middle cerebral artery occlusion/reperfusion (MCAO/R) rats. Then, we knocked down or overexpressed ALK5 with lentivirus (LV) in vivo. ALK5 knockdown reduced axonal and dendritic plasticity, with a concomitant decrease in neurological function recovery. Conversely, ALK5 overexpression significantly increased neurogenesis as well as functional recovery. Furthermore, ALK5 mediated Gadd45b protein levels by regulating Smad2/3 phosphorylation. Finally, ALK5 coimmunoprecipitated with Gadd45b. Our results suggested that the ALK5 signaling pathway plays a critical role in mediating neural plasticity and neurological function recovery via Gadd45b after cerebral ischemia, representing a new potential target for cerebral I/R injury.

12.
J Orthop Surg Res ; 14(1): 122, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31068193

RESUMO

BACKGROUND: To compare the biomechanical characteristics of different posterior intermediate screw fixation techniques (ISFTs) with hybrid monoaxial pedicle screws (Mps) and polyaxial pedicle screws (Pps) used in thoracolumbar burst fractures. METHODS: Fixation techniques are compared with regard to the von Mises stress (VMS) of the instrumentations and intradiscal pressures (IDPs) of the adjacent segments by finite element method (FEM). RESULTS: The redistributed ROM of the fixation models with Pps fixed at the lowest segment was twice of the other fixation models in flexion and extension. The largest value of maximal VMS of a pedicle screw was located at the lowest pedicle screws when Mps are fixed at the lowest segment. The largest value of maximal VMS of the rods was decreased when more Pps are fixed at the models. Maximal IDPs of the upper adjacent segments were all larger than those of the lower adjacent segments. The maximal IDPs of the fixation model with MPs fixed at the lowest segment were larger than the other fixation models in flexion and extension. CONCLUSIONS: Polyaxial pedicle screws could be placed at the upper or the median segment for the facilitated efficient application of the connecting rod. We should focus on the adjacent segmental degeneration especially the upper adjacent segment in the fixation model with Mps fixed at the lowest segment.

13.
Appl Opt ; 58(4): 1084-1092, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874158

RESUMO

X-ray luminescence computed tomography (XLCT) is an emerging hybrid imaging modality. It has been recently reported that materials such as water, tissue, or even air can generate optical photons upon x-ray irradiation, which can increase the noises in measurements of XLCT. In this study, we have investigated the x-ray luminescence from water, air, as well as tissue mimicking phantoms, including one embedded with a 0.01 mg/mL GOS:Eu3+ microphosphor target. We have measured the optical emission spectrum from each sample, including samples of meat and fat, using a spectrograph. Our results indicate that there are plenty of optical photons emitted by x-ray irradiation, and a small nanophosphor concentration, as low as 5.28 µM in a deep background, can provide enough contrast for XLCT imaging.

15.
J Proteome Res ; 18(5): 2021-2031, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-30908922

RESUMO

For individuals migrating to or residing permanently in high-altitude regions, environmental hypobaric hypoxia is a primary challenge that induces several physiological or pathological responses. It is well documented that human beings adapt to hypobaric hypoxia via some protective mechanisms, such as erythropoiesis and overproduction of hemoglobin; however, little is known on the alterations of plasma proteome profiles in accommodation to high-altitude hypobaric hypoxia. In the present study, we investigated differential plasma proteomes of high altitude natives and lowland normal controls by a TMT-based proteomic approach. A total of 818 proteins were identified, of which 137 were differentially altered. Bioinformatics (including GO, KEGG, protein-protein interactions, etc.) analysis showed that the differentially altered proteins were basically involved in complement and coagulation cascades, antioxidative stress, and glycolysis. Validation results demonstrated that CCL18, C9, PF4, MPO, and S100A9 were notably up-regulated, and HRG and F11 were down-regulated in high altitude natives, which were consistent with TMT-based proteomic results. Our findings highlight the contributions of complement and coagulation cascades, antioxidative stress, and glycolysis in acclimatization to hypobaric hypoxia and provide a foundation for developing potential diagnostic or/and therapeutic biomarkers for high altitude hypobaric hypoxia-induced diseases.

16.
J Proteomics ; 194: 60-69, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30605725

RESUMO

High-altitude polycythemia (HAPC) is one of the classic chronic mountain sicknesses and has been a serious public health problem in high-altitude regions. Despite numerous studies on HAPC via genomics or transcriptomics approaches, the pathogenesis of HAPC is still unclear. Here, we performed a TMT- based comparative quantitative proteomics analysis to reveal the changes of plasma proteomics profiles between HAPC subjects and healthy controls. Of identified 818 proteins, 7 and 12 proteins were up-regulated and down-accumulated, respectively, compared HAPC patients with healthy controls. GO and KEGG pathway analyses revealed the dysregulated proteins were primarily involved in complement and coagulation cascades, inflammation and immune response. ELISA validation demonstrated that C4A, C6 and CALR were down-regulated, and MASP1 and CNDP1 were up-regulated in HAPC patients. By ROC analysis, combinations of these five proteins (i.e., C4A, C6, CALR, MASP1 and CNDP1) resulted in a high AUC value (0.919; 95% CI, 0.817-961; p < .0001) to diagnose HAPC patients. Moreover, CNDP1 seems to be a robust biomarker for HAPC. This study not only provided a comprehensive dataset on overall proteomics changes in HAPC patients compared with healthy controls, but also indicated that CNDP1 can serve as a strong plasma biomarker of HAPC for the diagnostic and therapeutic potential. SIGNIFICANCE: HAPC, one of the classic chronic mountain sicknesses, has been a serious public health problem in high-altitude regions. Despite numerous studies on HAPC via genomics or transcriptomics approaches, the pathogenesis of HAPC is still largely unknown to date. In this study, we addressed this issue by performing TMT-based quantitative analyses of the plasma proteome profiles of HAPC patients and healthy controls. We identified 818 proteins, of which 19 were differentially expressed. Bioinformatics analysis revealed the differentially expressed proteins were mainly involved in complement and coagulation cascades, inflammation and immune response. By ROC analysis, combinations of C4A, C6, CALR, MASP1 and CNDP1 resulted in a high AUC value (0.919, p < .0001) to distinguish HAPC patients from healthy controls. Collectively, the current study provided a comprehensive dataset on overall proteomic changes in HAPC patients for the first time, and it also revealed C4A, C6, CALR, MASP1 and CNDP1 can be served as candidate plasma biomarkers of HAPC for their diagnostic and therapeutic potential.

17.
Chem Asian J ; 14(10): 1676-1680, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30644643

RESUMO

Herein, we report two novel derivatives of hexabenzoperylene (HBP) that are functionalized with ester groups. Methyl acetate functionalized HBP (1) in single crystals self-assembles into a supramolecular nanosheet, which has a two-dimensional π-stack of HBP sandwiched between two layers of ester groups. With the same self-assembly motif, active ester-functionalized HBP (2) in field effect transistors has enabled differentiation of tertiary amines from primary and secondary amines, in agreement with the fact that active ester reacts with primary and secondary amines but not with tertiary amines to form amides.

18.
Hematology ; 24(1): 325-330, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30669960

RESUMO

OBJECTIVE: To explore the correlations between RBCs indexes and the basic coagulation parameters, and provide data for further studies on high altitude-induced thrombotic disease. METHODS: A total of eligible 433 volunteers were divided into different groups according to HGB concentration and HCT, respectively. PT, APTT, TT and Fbg were measured by clotting assays. HGB content, HCT and PLT count were assessed by automated hematology analyzer. RESULTS: APTT and PT were significantly higher in group 4 (high HGB or HCT groups) (p < 0.05 for all comparison) and PLT count was significantly lower in group 4 than in other groups (p < 0.01 for all comparison). APTT and PT showed negative correlations with HGB concentration (r = -0.168 and -0.165 resp.; both p < 0.01), whereas positive correlations were found between APTT and HCT, PT and HCT (r = 0.225 and 0.258, resp.; both p < 0.01). PLT, TT and Fbg showed no correlation with HGB and HCT. CONCLUSIONS: HGB and HCT may not correlate with basic coagulation parameters in high altitude population, their predictive value for high altitude-induced thrombotic disease may relatively independent and this remain to be determined in further studies.


Assuntos
Altitude , Coagulação Sanguínea/fisiologia , Eritrócitos/metabolismo , Hemoglobinas/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Medicine (Baltimore) ; 98(4): e13961, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30681556

RESUMO

To investigate the age, gender, and etiology differences of sports-related fractures in children and adolescents (6-18 years old).We retrospectively reviewed 410 child and adolescent patients (335 males and 75 females aged 13.5 ±â€Š3.1 years old) with sports-related fractures admitted to our university-affiliated hospitals from 2001 to 2010. The incidence and pattern were summarized with respect to different age groups, genders, etiologies.Playing basketball (97, 23.7%) and running (90, 22.0%) were the most common etiologies. Radius (102, 24.9%) was the most common fracture site. The most common etiologies and fracture sites were biking (19.6%) and humerus fractures (28.0%) in the ≤12 age range group, playing basketball (34.0%) and radius fractures (26.2%) in the 12-15 age range group, playing basketball (31.7%) and radius fractures (23.0%) in the 15-18 age range group. The most common etiologies were playing basketball (27.5%) in the male group and running (24.0%) in the female group. The male presented with significantly higher rate of radius fractures and nerve injury, significantly lower rate of femoral fractures than the female. The most common fracture sites were radius fractures in the basketball group (28.9%) and cricket group (37.5%), humerus fracture in the running group (20.0%), biking group (23.3%), and climbing group (45.0%), tibia fractures in the football group (28.9%) and playing SP bars group (50.0%), and ulna fractures (37.5%) in the ice skating group.Sports-related fractures are common in children and adolescents, particularly in males. Basketball, running, and biking were the most common etiologies; radius, ulna, and humerus were the most common fracture sites.


Assuntos
Traumatismos em Atletas/epidemiologia , Fraturas Ósseas/epidemiologia , Adolescente , Fatores Etários , Traumatismos em Atletas/classificação , Criança , China/epidemiologia , Feminino , Fraturas Ósseas/classificação , Humanos , Masculino , Estudos Retrospectivos , Fatores Sexuais
20.
Antiviral Res ; 163: 59-69, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30639438

RESUMO

Alphaviruses such as the Venezuelan equine encephalitis virus (VEEV) are important human emerging pathogens transmitted by mosquitoes. They possess a unique viral mRNA capping mechanism catalyzed by the viral non-structural protein nsP1, which is essential for virus replication. The alphaviruses capping starts by the methylation of a GTP molecule by the N7-guanine methyltransferase (MTase) activity; nsP1 then forms a covalent link with m7GMP releasing pyrophosphate (GT reaction) and the m7GMP is next transferred onto the 5'-diphosphate end of the viral mRNA to form a cap-0 structure. The cap-0 structure decreases the detection of foreign viral RNAs, prevents RNA degradation by cellular exonucleases, and promotes viral RNA translation into proteins. Additionally, reverse-genetic studies have demonstrated that viruses mutated in nsP1 catalytic residues are both impaired towards replication and attenuated. The nsP1 protein is thus considered an attractive antiviral target for drug discovery. We have previously demonstrated that the guanylylation of VEEV nsP1 can be monitored by Western blot analysis using an antibody recognizing the cap structure. In this study, we developed a high throughput ELISA screening assay to monitor the GT reaction through m7GMP-nsP1 adduct quantitation. This assay was validated using known nsP1 inhibitors before screening 1220 approved compounds. 18 compounds inhibiting the nsP1 guanylylation were identified, and their IC50 determined. Compounds from two series were further characterized and shown to inhibit the nsP1 MTase activity. Conversely, these compounds barely inhibited a cellular MTase demonstrating their specificity towards nsP1. Analogues search and SAR were also initiated to identify the active pharmacophore features. Altogether the results show that this HT enzyme-based assay is a convenient way to select potent and specific hit compounds targeting the viral mRNA capping of Alphaviruses.

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