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1.
Ultrason Sonochem ; 67: 105167, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32442929

RESUMO

Electrokinetic potential of particles has been extensively studied in colloidal systems over the past century, while up to date, the influence of gas on electrokinetic behaviors of particles has not been fully understood yet. In this study, the electrokinetic response of particles to gas nucleation was systematically investigated with coal as the object. The results showed that the nucleation of gas (both on particle surfaces and in water) significantly changed the particle' electrokinetic behaviors. Higher gas content and particle's surface hydrophobicity normally trigger more intensive gas nucleation, thus inducing more significant reduction of particle zeta potential. After gas nucleation, numerous nanobubbles (NBs) appear in the suspensions mainly in two forms: NBs adhering onto solid surfaces (ANBs) and NBs stagnating in bulk solutions (BNBs). ANBs not only enhance the surface heterogeneity, but also cause the "steric hindrance" effect, and electric double layer (EDL) overlapping and associated ions shielding towards charged particles, which significantly decrease their electrokinetic potentials. Although BNBs can also reduce the zeta potential of particles by EDL compressing, their functions are rather limited.

2.
Clin Interv Aging ; 15: 595-607, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431493

RESUMO

Purpose: Perceived social support (PSS) is closely linked to health outcomes in dementia patients. However, its continuous benefits are unclear. This mixed-methods study examined the impact of social support perceptions and differentiation among patients and carers during disease progression. Patients and Methods: Persons with dementia (PWDs), family caregivers, and community family physicians were recruited from nine community health centers. Semi-structured interviews conducted with 12 PWDs (7 PWDs in mild dementia and 5 in moderate dementia), 12 family caregivers, and 6 community family physicians and conventional content analysis were used to explore social support perspectives at different dementia stages. A total of 470 PWDs were divided into mild (n=224), moderate (n=190), and severe (n=56) groups. Demographic, physical, and psychological factors related to PSS were examined by the group using multiple regression analysis. The group-based characteristics were entered into three prediction models. Results: In the qualitative study, three themes of social support were identified: two viewpoints refer to social support; different needs and preferences in each stage; non-personalized support services. Quantitatively, the mild group scored lowest in perceived social support, while the severe group scored highest (χ2=64.70, P<0.001). The mild group PSS was predicted by depression (ß=-0.07, P=0.04), cognitive capacity (ß=-0.18, P<0.001), and instrumental ability (ß=-0.78, P<0.001), which differed from the moderate and severe groups. Conclusion: This study provided comprehensive insight into PSS from PWDs' perspective at different stages of the disease. Results indicated the need for a stratified care approach and direction for further research on intervention.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32224457

RESUMO

Existing enhancement methods are empirically expected to help the high-level end computer vision task: however, that is observed to not always be the case in practice. We focus on object or face detection in poor visibility enhancements caused by bad weathers (haze, rain) and low light conditions. To provide a more thorough examination and fair comparison, we introduce three benchmark sets collected in real-world hazy, rainy, and low-light conditions, respectively, with annotated objects/faces. We launched the UG2+ challenge Track 2 competition in IEEE CVPR 2019, aiming to evoke a comprehensive discussion and exploration about whether and how low-level vision techniques can benefit the high-level automatic visual recognition in various scenarios. To our best knowledge, this is the first and currently largest effort of its kind. Baseline results by cascading existing enhancement and detection models are reported, indicating the highly challenging nature of our new data as well as the large room for further technical innovations. Thanks to a large participation from the research community, we are able to analyze representative team solutions, striving to better identify the strengths and limitations of existing mindsets as well as the future directions.

5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(2): 682-685, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32319416

RESUMO

Abstract  Chemokines and their receptors play an important role in development and migration of normal immune cells. In recent years, relevant studies have shown that the expression of chemokine receptor on the surface of non-Hodgkin's lymphoma cells is up-regulated, which regulates the disease's occurrence and metastasis, and influences prognosis of patients. Agents targeting chemokine receptors are under research and applied in hematopoietic stem cell mobilization and anti-lymphoma therapy. A new family of atypical chemokines has been gradually discovered and shown the anti-lymphoma effect, which is potential to become a new theraputic method. In this review, the research advance of chemokines and their receptors in non-Hodgkin's lymphoma is summarized.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32272011

RESUMO

For converting the renewable solar energy to hydrogen (H2) energy by photocatalytic (PC) overall water splitting (OWS), visible-light-driven photocatalysts are especially desired. Herein, a model CdS/g-C3N4 photocatalyst with a type II heterojunction is first demonstrated via a facile coupling of g-C3N4 nanosheets and CdS nanorods. After being combined with in situ photodeposited 3 wt % Pt and 4 wt % MnOx dual cocatalysts simultaneously, the optimal visible-light-driven (λ > 400 nm) composite photocatalyst of Pt-CdS/g-C3N4-MnOx gives a H2 generation rate of 9.244 µmol h-1 (924.4 µmol h-1 g-1) and a O2 evolution rate of 4.6 µmol h-1 (460 µmol h-1 g-1) in pure water, which is over 420 times higher than that of pure CdS nanorods loaded with 0.5 wt % Pt. The apparent quantum efficiency (AQE) reaches about 3.389% (at 400 nm) and 1.745% (at 420 nm), respectively. The combination of a type II heterojunction and simultaneous in situ photodeposition of the dual cocatalysts results in a dramatically improved PC efficiency and a long-term stability of the CdS/g-C3N4 visible-light-driven photocatalyst for OWS.

7.
Clin Infect Dis ; 2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32198501

RESUMO

BACKGROUND: Emergence of coronavirus disease 2019 (COVID-19) is a major healthcare threat. Current method of detection involves qPCR-based technique, which identifies the viral nucleic acids when present in sufficient quantity. False negative results can be achieved and failure to quarantine the infected patient would be a major setback in containing the viral transmission. We here aim to describe the time kinetics of various antibodies produced against the 2019 novel coronavirus (SARS-CoV-2) and evaluate the potential of antibody testing to diagnose COVID-19. METHODS: The host humoral response against SARS-CoV-2 including IgA, IgM and IgG response were examined by using an ELISA based assay on the recombinant viral nucleocapsid protein. Total 208 plasma samples were collected from 82 confirmed and 58 probable cases (qPCR negative but had typical manifestation). The diagnostic value of IgM was evaluated in this cohort. RESULTS: The median duration of IgM and IgA antibody detection were 5 days (IQR 3-6), while IgG was detected on 14 days (IQR 10-18) after symptom onset, with a positive rate of 85.4%, 92.7% and 77.9% respectively. In confirmed and probable cases, the positive rates of IgM antibodies were 75.6% and 93.1%, respectively. The detection efficiency by IgM ELISA is higher than that of qPCR method after 5.5 days of symptom onset. The positive detection rate is significantly increased (98.6%) when combined IgM ELISA assay with PCR for each patient compare with a single qPCR test (51.9%). CONCLUSIONS: Humoral response to SARS-CoV-2 can aid to the diagnosis of COVID-19, including subclinical cases.

8.
Clin Infect Dis ; 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32221523

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) has become a public health emergency. The widely used reverse transcription PCR (RT-PCR) method has limitations for clinical diagnosis and treatment. METHODS: A total of 323 samples from 76 COVID-19 confirmed patients were analyzed by droplet digital PCR (ddPCR) and RT-PCR based two target genes (ORF1ab and N). Nasal swabs, throat swabs, sputum, blood, and urine were collected. Clinical and imaging data were obtained for clinical staging. RESULTS: In 95 samples tested positive by both methods, the cycle threshold (Ct) of RT-PCR was highly correlated with the copy numbed of ddPCR (ORF1ab gene, R2 = 0.83; N gene, R2 = 0.87). 4 (4/161) negative and 41 (41/67) single-gene positive samples tested by RT-PCR were positive according to ddPCR with viral load ranging from 11.1 to 123.2 copies/test. Then the viral load of respiratory samples was compared and the average viral load in sputum (17429 ± 6920 copies/test) was found to be significantly higher than in throat swabs (2552 ± 1965 copies/test, p < 0.001) and nasal swabs (651 ± 501 copies/test, p < 0.001). Furthermore, the viral load in the early and progressive stages were significantly higher than that in the recovery stage (46800 ± 17272 vs 1252 ± 1027, p < 0.001) analyzed by sputum samples. CONCLUSIONS: Quantitative monitoring of viral load in lower respiratory tract samples helps to evaluate disease progression, especially in cases of low viral load.

9.
J Trop Pediatr ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040187

RESUMO

Previous studies have shown that the CareStart™ G6PD Deficiency rapid diagnostic test has high diagnostic accuracy on G6PD deficiency in Africa and Thailand, but not in China. As there are regional differences of G6PD genotype distribution, we are attending to verify the effectiveness of the kit in Chinese population. The study cohort included 247 newborns admitted to our hospital for jaundice. The quantitative detection of G6PD enzyme activity and G6PD gene mutations analysis was used to classify the status of G6PD deficiency. The performance of CareStart™ assays was verified by calculating the sensitivity, specificity and area under the receiver operating characteristic curve (AUC) based on the corrected G6PD deficiency status. In male newborns, the sensitivity of the CareStart™ assay was 98.9%, the specificity was 94.2% and the AUC was 0.97. In female newborns, the sensitivity was 58.5% when the cutoff value of residual enzyme activity was 100%; however, the sensitivity was 100% when the cutoff value was 60%. Therefore, the CareStart™ test can effectively screen G6PD deficiency in male newborns and female infants with less than 60% residual enzyme activity, female infants with residual enzyme activities of 60-100% are more likely to be missed diagnosed among Chinese newborns.

10.
Chemosphere ; 239: 124831, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31526986

RESUMO

The overuse of antibiotics, including tetracycline hydrochloride (TC), seriously threatens human health and ecosystems. In this work, magnetic carbon-coated cobalt oxide nanoparticles (CoO@C) were prepared by one-step annealing method and used as an adsorbent for efficient removal of TC from aqueous solution. The characteristic of the materials was studied by SEM, TEM, and XRD, revealing CoO nanoparticles (≤10 nm) were coated by carbon layer. Several influencial parameters, such as annealing temperature and pH on adsorption of TC, were explored, and found that the maximum adsorption capacity of CoO@C on TC reached as high as 769.43 mg g-1. Furthermore, CoO@C displayed excellent stability and reusability. After four repeated use of the adsorbent, the adsorption capacity still remained at 90% of the initial capacity. The pseudo-second order model and Temkin model proved that it was an exothermic chemical adsorption process. Furthermore, after analysis of FT-IR, Zeta-potential, XPS, the positive charge on the surface of CoO@C forms a strong electrostatic interaction with TC, and in addition, a surface bond is formed between the adsorbent and the TC molecule. This work provides a novel and efficient adsorbent for the purification of TC-containing wastewater.


Assuntos
Cobalto/química , Nanopartículas/química , Óxidos/química , Tetraciclina/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Antibacterianos/química , Carbono , Magnetismo , Reciclagem , Tetraciclina/isolamento & purificação , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
12.
Science ; 366(6465): 613-620, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31672893

RESUMO

The separation of hydrogen isotopes for applications such as nuclear fusion is a major challenge. Current technologies are energy intensive and inefficient. Nanoporous materials have the potential to separate hydrogen isotopes by kinetic quantum sieving, but high separation selectivity tends to correlate with low adsorption capacity, which can prohibit process scale-up. In this study, we use organic synthesis to modify the internal cavities of cage molecules to produce hybrid materials that are excellent quantum sieves. By combining small-pore and large-pore cages together in a single solid, we produce a material with optimal separation performance that combines an excellent deuterium/hydrogen selectivity (8.0) with a high deuterium uptake (4.7 millimoles per gram).

13.
Cancer Biomark ; 26(4): 441-449, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31640082

RESUMO

BACKGROUND: ACOT plays an important role in lipid metabolism and recent studies found that ACOT participates in some kinds of tumorigenesis. However, both the role of ACOT and its significance have not been revealed in AML. Therefore, we conduct this study in order to investigate the association between AML and ACOT, and hopefully contributed to the management of AML. METHODS: One hundred and fifty-six AML patients were enrolled in our study whose data were derived from the Cancer Genome Atlas database. There were 85 patients who received only chemotherapy and other 71 patients underwent allo-HSCT. RESULTS: Patients in high ACOT7 group had a significant lower EFS and OS, while patients in high versus low expression levels of other types of ACOT showed no significant difference on the outcome. High level of ACOT7 related with poor outcome in both chemotherapy-only group and HSCT group. CONCLUSIONS: High expression level of ACOT7 indicates unfavorable outcome in AML patients. Allo-HSCT could not overcome the unfavorable effect of ACOT7 in these patients.

14.
Materials (Basel) ; 12(19)2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31561431

RESUMO

This paper investigates the progressive damage and failure behavior of unidirectional graphite fiber-reinforced aluminum composites (CF/Al composites) under transverse and longitudinal tensile loadings. Micromechanical finite element analyses are carried out using different assumptions regarding fiber, matrix alloy, and interface properties. The validity of these numerical analyses is examined by comparing the predicted stress-strain curves with the experimental data measured under transverse and longitudinal tensile loadings. Assuming a perfect interface, the transverse tensile strength is overestimated by more than 180% and the transverse fracture induced by fiber failure is unrealistic based on the experimental observations. In fact, the simulation and experiment results indicate that the interface debonding arising from the matrix alloy failure dominates the transverse fracture, and the influence of matrix alloy properties on the mechanical behavior is inconspicuous. In the case of longitudinal tensile testing, however, the characteristic of interface bonding has no significant effect on the macroscopic mechanical response due to the low in-situ strength of the fibers. It is demonstrated that ultimate longitudinal fracture is mainly controlled by fiber failure mechanisms, which is confirmed by the fracture morphology of the tensile samples.

15.
ChemSusChem ; 12(22): 4996-5006, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31529775

RESUMO

Considerable research efforts have been devoted to develop noble-metal-free cocatalysts coupled with semiconductors for highly efficient photocatalytic H2 evolution as part of the challenge toward solar-to-fuel conversion. Herein, a new cocatalyst with excellent activity in the electrocatalytic H2 evolution reaction (HER) that is based on Co sheathed in N-doped graphitic carbon nanosheets (Co@NC) was fabricated by a surfactant-assisted pyrolysis approach and then coupled with g-C3 N4 nanosheets to construct a 2 D-2 D g-C3 N4 /Co@NC composite photocatalyst by a simple grinding method. As a result of advantages in effective electrocatalytic HER activity, suitable electronic band structure, and rapid interfacial charge transfer brought about by the 2 D-2 D spatial configuration, the g-C3 N4 /Co@NC photocatalyst that contained 4 wt % Co@NC presented a high photocatalytic H2 generation rate of 15.67 µmol h-1 under visible-light irradiation (λ≥400 nm), which was 104.5 times higher than that of pristine g-C3 N4 . The optimum g-C3 N4 /Co@NC photocatalyst showed a high apparent quantum efficiency of 10.82 % at λ=400 nm.

16.
Chem Asian J ; 14(19): 3431-3441, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31529794

RESUMO

Highly efficient and easy recyclable monolithic photocatalysts with ideal separation/transport route for photogenerated charge carriers are much desired. In this work, a ZnO seed-induced growth approach is developed to fabricate a ternary monolithic photomembrane, that is, ZnS/CdS heterojunction nanorods in situ grow into the interspaces of multilayer reduced graphene oxide (rGO) sheets (denoted as ZnS/CdS/rGO). The monolithic ZnS/CdS/rGO photomembrane can serve as an efficient visible-light photoactive membrane for photocatalytic (PC) or photoelectrochemical (PEC) hydrogen generation. The fast electron transport of 1D CdS nanorods, the excellent electronic conductivity of multilayer stacked rGO sheets, the intense visible-light absorption of CdS, the unique hierarchical structure, and double heterojunctions (ZnS/CdS and CdS/rGO) efficiently boost the photogenerated electron-hole pairs separation and transfer across the interfacial domain of the photomembrane under visible-light irradiation. Furthermore, the superior stability and reusability of the photomembrane is achieved by the ideal process of photogenerated electron-hole pair separation/transfer, i.e., holes transfer to ZnS and electrons transfer to rGO to inhibit CdS from photocorrosion.

17.
J Cancer ; 10(18): 4286-4292, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413748

RESUMO

Background: Actinins are major cytoskeletal proteins that mediate sarcomere function, and they also have important non-muscle functions such as regulating cytokinesis, cell adhesion and migration. There are four isoforms of actinins in mammals (ACTN1-4). Recently, the relationship between actinins and cancer has been discovered in many types of malignancy, yet their prognostic significance in acute myeloid leukemia (AML) remains unclear. Methods: We collected data of 155 de novo AML patients from The Cancer Genome Atlas (TCGA) database; 85 patients received chemotherapy only and 70 patients underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). We divided each treatment groups into sub-groups based on the median expression levels of ACTN1-4. Results: Survival analysis showed that in the chemotherapy-only group, high ACTN1 and ACTN3 expression were associated with shorter event-free survival (EFS) and overall survival (OS) (p<0.01). Multivariate analysis suggested that high expression of ACTN1 and ACTN3 (p<0.05) were independent poor prognostic factors. In the allo-HSCT group, ACTN1-4 expression had no impact on survival. Conclusions: Our study suggested that high expression levels of ACTN1 and ACTN3 adversely affected the survival of AML patients, but their harmful impact could be overcome by allo-HSCT.

18.
BMC Neurol ; 19(1): 166, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315588

RESUMO

BACKGROUND: Acquired epileptiform opercular syndrome (AEOS) with electrical status epilepticus during sleep (ESES) may be recurrent and intractable. The real-time transcranial Doppler ultrasound-sleep-deprived video electroencephalogram (TCD-SDvEEG) can be used to observe the relationships among hemodynamic, electrophysiological, and clinical factors in a patient during therapy. This study reported the case of a healthy 5-year-old boy with AEOS. CASE PRESENTATION: The patient had initial seizures during sleep at the age of 1 year, with the left mouth pouting, left eye blinking and drooling for several seconds, and, sometimes, the left upper-limb flexion and head version to the left, lasting for 1-2 min. The combined antiepileptic drug regimens, including valproate, lamotrigine, and clonazepam, failed in the present case. Therefore, the add-on high-dose methylprednisolone therapy was provided. Also, the serial TCD-SDvEEG was used to monitor the dynamic changes before and after add-on steroid treatment. The results showed less than 15% variation in the range of blood flow fluctuation with spikes during non-rapid eye movement sleep after treatment. This was similar to the outcomes in healthy children and also accorded with the clinical improvements such as seizure control, drooling control, and language ability melioration. However, 95% of spike-wave index (SWI) was still maintained. The improvements in cerebral hemodynamics and clinical manifestations were faster and earlier than the SWI progression. CONCLUSIONS: The real-time TCD-SDvEEG was highly sensitive in detecting therapeutic changes. The findings might facilitate the understanding of the mechanisms underlying neurovascular coupling in patients with AEOS accompanied by ESES.


Assuntos
Eletroencefalografia/métodos , Transtornos do Sono-Vigília/diagnóstico , Estado Epiléptico/diagnóstico , Anticonvulsivantes/uso terapêutico , Pré-Escolar , Humanos , Masculino , Metilprednisolona/uso terapêutico , Convulsões/tratamento farmacológico , Sono/fisiologia , Transtornos do Sono-Vigília/fisiopatologia , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/fisiopatologia , Síndrome , Falha de Tratamento , Ultrassonografia Doppler Transcraniana , Ácido Valproico/uso terapêutico
19.
Oncol Lett ; 17(6): 5793-5802, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31186806

RESUMO

The aim of the present study was to investigate whether the expression levels of microRNA-425 (miR-425) were associated with the prognosis of acute myeloid leukemia (AML) in patients treated with chemotherapy or allogeneic hematopoietic stem cell transplantation (allo-HSCT). A total of 162 AML patients were enrolled and divided into chemotherapy and allo-HSCT groups. Next, the overall survival (OS) and event-free survival (EFS) were compared between patients with high and low miR-425 expression in each of the treatment groups. In the chemotherapy group, high miR-425 expression was favorable for EFS (P=0.001) and OS (P=0.001) in younger patients (<60 years), whereas it had no effect on EFS and OS in older patients (≥60 years). In the allo-HSCT group, there was no association between miR-425 expression levels and clinical outcomes. Further analyses suggested that in the low miR-425 expression group, EFS and OS were longer in patients treated with allo-HSCT as compared with those treated with chemotherapy (both P<0.001), whereas no significant differences were observed in the high miR-425 expression group. In conclusion, the current data indicated that miR-425 is an independent favorable prognostic factor for younger AML patients undergoing chemotherapy, and its use may facilitate clinical decision-making in selecting treatment for AML patients. Patients with low miR-425 expression may benefit from allo-HSCT, whereas allo-HSCT did not appear to be beneficial in patients with high miR-425 expression.

20.
Oncol Lett ; 17(6): 5815-5820, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31186809

RESUMO

MicroRNA-500 (miR-500) is a potential prognostic biomarker in a number of different types of cancer, such as prostate cancer and hepatocellular carcinoma. This study aimed to explore the clinical implications of miR-500 expression status in patients with acute myeloid leukemia (AML) that had received allogeneic hematopoietic stem cell transplantation (allo-HSCT). miR-500 expression status and clinical data were obtained from 74 patients with AML in the The Cancer Genome Atlas database receiving allo-HSCT. Patients with low expression level of miR-500 (miR-500low) were significantly more likely to present with a French-American-British classification M2 subtype (P=0.003), and less likely to have the M5 subtype (P=0.040) compared with patients with high expression levels (miR-500high). miR-500low patients were associated with low-risk AML (P=0.003) and core-binding factor subunit b-myosin heavy chain 11 translocation mutation (P=0.021). There was a significant difference in nucleophosmin 1 (P=0.009), NRAS proto-oncogene GTPase/KRAS proto-oncogene GTPase (P=0.047) and PHD finger protein 6 (P=0.040) expression levels between the two groups. miR-500high patients had a decreased overall survival (OS) time compared with the low expression group (P=0.035). Multivariate analysis revealed that miR-500 expression significantly affected OS time independent of other classical prognostic factors, such as age and common mutations. The analysis of survival curves further substantiated this result. The results obtained in the current study suggested that miR-500 may be a suitable prognostic marker for patients with AML receiving allo-HSCT.

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