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1.
Infect Immun ; : IAI0039621, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34310892

RESUMO

To develop an effective Pseudomonas aeruginosa (PA) outer-membrane-vesicles (OMVs) vaccine, we eliminated multiple virulence factors from a wild-type P. aeruginosa PA103 strain (PA103) to generate a recombinant strain, PA-m14. The PA-m14 strain was tailored with a pSMV83 plasmid encoding the pcrV-hitAT fusion gene to produce OMVs. The recombinant OMVs enclosed increased amounts of PcrV-HitAT bivalent antigen (PH) (termed OMV-PH) and exhibited reduced toxicity compared to the OMVs from PA103. Intramuscular vaccination with OMV-PH from PA-m14(pSMV83) afforded 70% protection against intranasal challenge with 6.5 × 106 CFU (∼30 LD50) of PA103, while immunization using OMVs without the PH antigen (termed OMV-NA) or the PH antigen alone failed to offer effective protection against the same challenge. Further immune analysis showed that the OMV-PH immunization significantly stimulated potent antigen-specific humoral and T-cell (Th1/Th17) responses in comparison to the PH or OMV-NA immunization in mice, which can effectively hinder PA infection. Undiluted anti-sera from OMV-PH-immunized mice displayed significant opsonophagocytic killing of WT PA103 compared to antisera from PH antigen- or OMV-NA-immunized mice. Moreover, the OMV-PH immunization afforded significant antibody-indentpednet cross-protection to mice against PAO1 and a clinical isolate AMC-PA10 strains. Collectively, the recombinant PA OMV delivering the PH bivalent antigen exhibits high immunogenicity and would be a promising next-generation vaccine candidate against PA infection.

2.
Neurocrit Care ; 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34313936

RESUMO

BACKGROUND: Studies of the impact of increased hemoglobin on spontaneous intracerebral hemorrhage (ICH) are limited. The present study aimed to explore the effect of increased hemoglobin on ICH. METHODS: A retrospective single-center study using medical records from a database processed by univariate and multivariate analyses was performed in the People's Hospital of Tibet Autonomous Region in Lhasa, Tibet, China. RESULTS: The mean hemoglobin level in 211 patients with ICH was 165.03 ± 34.12 g/l, and a median hematoma volume was 18.5 ml. Eighty-eight (41.7%) patients had large hematomas (supratentorial hematoma ≥ 30 ml; infratentorial hematoma ≥ 10 ml). No differences in ICH risk factors between the groups with different hemoglobin levels were detected. Increased hemoglobin was independently associated with large hematomas [odds ratio (OR) 1.013, P = 0.023]. Increased hemoglobin was independently associated with ICH with subarachnoid hemorrhage (OR 1.014, P = 0.016), which was more pronounced in men (OR 1.027, P = 0.002). Increased hemoglobin was independently associated with basal ganglia hemorrhage and lobar hemorrhage in men (OR 0.986, P = 0.022; OR 1.013, P = 0.044, respectively) but not in women (P > 0.1). CONCLUSIONS: Increased hemoglobin was independently associated with large hemorrhage volume. Increased hemoglobin was independently associated with lobar hemorrhage in men and ICH with subarachnoid hemorrhage, which was more pronounced in men. Additional studies are needed to confirm our findings and explore potential mechanisms.

4.
Leuk Lymphoma ; : 1-10, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34304674

RESUMO

Patients with mycosis fungoides (MF) and Sézary syndrome (SS) often require multiple lines of systemic therapy. In the phase 3 MAVORIC study (NCT01728805), mogamulizumab demonstrated superiority to vorinostat in median progression-free survival (PFS) and confirmed overall response rate (ORR) in patients with MF/SS. This post hoc analysis examined the effects of number and type of prior systemic therapies on mogamulizumab response. MAVORIC patients randomized to mogamulizumab (1.0 mg/kg intravenously weekly) or vorinostat (400 mg orally daily) were grouped by number of prior therapies and immunomodulatory activity of immediate prior systemic therapy while also considering time elapsed since treatment. ORR, PFS, and duration of response (DOR) did not vary with number of prior therapies. ORR and DOR remained consistent regardless of immediate prior therapy type. Additionally, immunomodulatory activity of the last prior therapy and time from prior treatment generally did not affect the ORR or PFS observed in response to mogamulizumab.

5.
New Phytol ; 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34292587

RESUMO

Understanding processes that generate and maintain large disjunctions within plant species can provide valuable insights into plant diversity and speciation. The butterfly bush Buddleja alternifolia has an unusual disjunct distribution, occurring in the Himalaya, Hengduan Mountains (HDM) and the Loess Plateau (LP) in China. We generated a high-quality, chromosome-level genome assembly of B. alternifolia, the first within the family Scrophulariaceae. Whole genome resequencing data from 48 populations plus morphological and petal color reflectance data covering its full distribution range were collected. Three distinct genetic lineages of B. alternifolia were uncovered, corresponding to Himalayan, HDM and LP populations, with the last also differentiated morphologically and phenologically, indicating occurrence of allopatric speciation likely facilitated by geographic isolation and divergent adaptation to distinct ecological niches. Moreover, speciation with gene flow between populations from either side of a mountain barrier could be under way within LP. The current disjunctions within B. alternifolia might result from vicariance of a once widespread distribution, followed by several past contraction and expansion events, possibly linked to climate fluctuations promoted by the Kunlun-Yellow river tectonic movement. Several adaptive genes are likely either uniformly or diversely selected among regions, providing a footprint of local adaptations. These findings provide new insights into plant biogeography, adaptation and different processes of allopatric speciation.

6.
J Am Chem Soc ; 143(27): 10341-10351, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34213894

RESUMO

Genetically introducing novel chemical bonds into proteins provides innovative avenues for biochemical research, protein engineering, and biotherapeutic applications. Recently, latent bioreactive unnatural amino acids (Uaas) have been incorporated into proteins to covalently target natural residues through proximity-enabled reactivity. Aryl fluorosulfate is particularly attractive due to its exceptional biocompatibility and multitargeting capability via sulfur(VI) fluoride exchange (SuFEx) reaction. Thus far, fluorosulfate-l-tyrosine (FSY) is the only aryl fluorosulfate-containing Uaa that has been genetically encoded. FSY has a relatively rigid and short side chain, which restricts the diversity of proteins targetable and the scope of applications. Here we designed and genetically encoded a new latent bioreactive Uaa, fluorosulfonyloxybenzoyl-l-lysine (FSK), in E. coli and mammalian cells. Due to its long and flexible aryl fluorosulfate-containing side chain, FSK was particularly useful in covalently linking protein sites that are unreachable with FSY, both intra- and intermolecularly, in vitro and in live cells. In addition, we created covalent nanobodies that irreversibly bound to epidermal growth factor receptors (EGFR) on cells, with FSK and FSY targeting distinct positions on EGFR to counter potential mutational resistance. Moreover, we established the use of FSK and FSY for genetically encoded chemical cross-linking to capture elusive enzyme-substrate interactions in live cells, allowing us to target residues aside from Cys and to cross-link at the binding periphery. FSK complements FSY to expand target diversity and versatility. Together, they provide a powerful, genetically encoded, latent bioreactive SuFEx system for creating covalent bonds in diverse proteins in vitro and in vivo, which will be widely useful for biological research and applications.

7.
Mod Pathol ; 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253867

RESUMO

For neoadjuvant therapy in patients with non-small cell lung cancer, the major pathologic response of primary tumors may be an assessable and reliable surrogate measure of survival. Few studies have examined the pathologic evaluation of metastatic lymph node responses and their prognostic significance. This retrospective study enrolled 336 patients with non-small cell lung cancer (squamous cell carcinoma, n = 216; adenocarcinoma, n = 120) treated with neoadjuvant therapy including chemotherapy (n = 316) and targeted therapy (adenocarcinoma, n = 20). The treatment response of the primary tumor and lymph node metastases (LNM) were pathologically assessed according to the multidisciplinary recommendations of the International Association for the Study of Lung Cancer. The relationship of overall survival (OS) and disease-free survival (DFS) with the responses of the primary tumor or LNM was analyzed. The optimal cutoff value of the residual viable tumor (%RVT) of the primary tumor was 12% for both OS (P < 0.001) and DFS (P < 0.001). The pathologic assessment identified LNM in 208 patients. The optimal %RVT cutoff value in LNM was 8% for both OS (P = 0.003) and DFS (P < 0.001). The Spearman's rank correlation coefficient between primary tumors and corresponding LNM was 0.487 for %RVT (P < 0.001), which indicated a positive correlation. On multivariable analysis, an RVT of the primary tumor ≤12% was an independent prognostic factor for improved OS (P = 0.024), whereas an RVT of LNM ≤ 8% was an independent prognostic factor for increased DFS (P = 0.018). Furthermore, in the neoadjuvant chemotherapy group, the optimal %RVT cutoff values for OS in patients with squamous cell carcinoma and adenocarcinoma in the primary tumor were 12% and 58%, respectively. Considering its convenience and operability in clinical application, a 10% threshold RVT value can be used for prognostic evaluation of LNM and primary tumors of squamous cell carcinoma histology; further studies are needed to confirm the optimal cutoff value for primary tumors of adenocarcinoma.

8.
Pathol Oncol Res ; 27: 628942, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34257592

RESUMO

Mounting evidence suggests a causal relationship between specific bacterial infections and the development of certain malignancies. In this study, we examined the presence of Porphyromonas gingivalis (P. gingivalis) in oral-digestive tract tumors by immunohistochemistry (IHC) and PCR and analyzed the correlation between P. gingivalis detection and clinicopathological characteristics and prognosis of oral and esophageal carcinoma. The IHC results showed that the positive rates of P. gingivalis were 60.00, 46.00, 20.00, 6.67, and 2.86% in oral, esophagus, cardiac, stomach, and colorectal cancer tissues, respectively. Likewise, PCR results showed rates of 56.00, 42.00, 16.67, 3.33, and 2.86%, respectively. The two methods were consistent, and the kappa value was 0.806, P < 0.001. In addition, P. gingivalis expression was significantly correlated with lymph node metastasis and the clinical stages of oral and esophageal cancer (P < 0.05). The overall survival rate of the P. gingivalis undetected group (86, 50%) was significantly higher than that of the P. gingivalis detected group (57, 14%) for oral and esophageal cancer, respectively. In conclusion, the detection rate of P. gingivalis showed a decreasing trend in oral-digestive tract tumors. Detection with P. gingivalis was associated with poor prognosis for oral and esophageal cancer.

9.
Environ Monit Assess ; 193(8): 476, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34232403

RESUMO

In this study, daily average PM2.5 forecasting models were developed and applied in the Northern Xinjiang, China, through combining the back propagation artificial neural network (BPANN) and multiple linear regression (MLR) with another BPANN model. The meteorological (daily average precipitation, pressure, relative humidity, temperature, and wind speed, daily maximum wind speed and sunshine hours on the same day) and air pollutant data (daily PM2.5, PM10, SO2, CO, NO2, and O3 concentrations on the previous day) in January and August of each year from 2015 to 2019 were used as candidate inputs. The optimal member and combining models were evaluated through the leave-one-out cross-validation (LOOCV), fivefold cross-validation, and hold-out methods. Twelve member models with optimal or sub-optimal performance were further used to develop the combining models. The performances of the BPANN and MLR member models were different using three data division methods. The models were evaluated more comprehensively through the LOOCV. The performances of the combining models were generally better than the member models. For both member and combining models, the PM2.5 forecasting model performance in August was generally better than in January. The correlation coefficient (R) for the validation set of the optimal combination model was about 0.87 in January and 0.946 in August. These results showed that combining linear and nonlinear models through multiple data division methods would be an effective tool to forecast PM2.5 concentrations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Previsões , Aprendizado de Máquina , Material Particulado/análise
10.
J Bacteriol ; : JB0023721, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34280001

RESUMO

The pH 6 antigen of Yersinia pestis is a virulence factor that is expressed in response to high temperature (37°C) and low pH (6.0). Previous studies have implicated the PsaE and PsaF regulators in the temperature- and pH-dependent regulation of psaA. Here, we show that PsaE levels are themselves controlled by pH and temperature, explaining the regulation of psaA. We identify hundreds of binding sites for PsaE across the Y. pestis genome, with the majority of binding sites located in intergenic regions bound by the nucleoid-associated protein H-NS. However, we detect direct regulation of only two transcripts by PsaE, likely due to displacement of H-NS from the corresponding promoter regions; our data suggest that most PsaE binding sites are non-regulatory, or that they require additional environmental cues. We also identify the precise binding sites for PsaE that is required for temperature- and pH-dependent regulation of psaA and psaE. Thus, our data reveal the critical role that PsaE plays in regulation of psaA, and suggest that PsaE may have many additional regulatory targets. Importance Y. pestis, the etiologic agent of plague, has been responsible for high mortality in several epidemics throughout human history. The plague bacillus has been used as a biological weapon during human history and is currently one of the most likely biological threats. PsaA and PsaE appear to play important roles during Y. pestis infection. Understanding their regulation via environmental cues would facilitate a solution to impede Y. pestis infection.

11.
Toxicol Lett ; 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34280503

RESUMO

Recent studies have reported that melamine can accumulate in several regions of the brain including the medial prefrontal cortex (mPFC). Although melamine accumulation in the hippocampus has been verified to induce cognitive impairments, whether it can cause mPFC-dependent working memory deficits is still unknown. After chronic treatment with melamine (150 (Mel(150)) or 300 (Mel(300)) mg/kg), rats were tested during both delay nonmatching-to-sample spatial and odor discrimination tasks. Levels of AMPA receptor subunits in the mPFC were detected using western blotting. To further explore the mechanism at the cellular level, prefrontal activity was recorded during the odor discrimination. The working memory of Mel(150) rats was found to be significantly impaired in a 3-minute delay odor discrimination task (control: n = 6, Mel(150): n = 6; P < 0.05). Compared with the control group (n = 6), rats in the 300 mg/kg Mel(300)-treated group (n = 8) displayed working memory deficits in 60-second delay Y-maze task (P < 0.05), 1-minute and 3-minute delay odor discrimination tasks (both P < 0.05). The levels of AMPA receptor mGluR2/3 subunit were significantly decreased in rats of the Mel(150) (n = 7) and Mel(300) (n = 7) groups (both P < 0.05). Exposure to 150 (n = 7) or 300 mg/kg (n = 7) melamine resulted in significant inhibition of the regular-spiking neuron activity during the delay period of the memory test (both P < 0.05). Intraperitoneal (n = 7) and intra-mPFC (n = 6) infusions of GluR2/3 agonists, effectively enhanced the neural correlate (both P < 0.05) while rescuing cognitive deficits in Mel(300)-treated rats (both P < 0.05). Collectively, these findings suggested that melamine could induce prefrontal dysfunction and cause cognitive impairments.

12.
Ecology ; : e03483, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34287849

RESUMO

Understanding the response of grassland production and carbon exchange to intra-annual variation in precipitation and nitrogen addition is critical for sustainable grassland management and ecosystem restoration. We introduced growing-season drought treatments of different lengths (15, 30, 45 and 60 day drought) by delaying growing-season precipitation in a long-term nitrogen addition experiment in a low diversity meadow steppe in northeast China. Response variables included aboveground biomass (AGB), ecosystem net carbon exchange (NEE), and leaf net carbon assimilation rate (A). In unfertilized plots drought decreased AGB by 13.7% after a 45 day drought and 31.7% after a 60 day drought (47.6% in fertilized plots). Progressive increases in the drought response of NEE were also observed. The effects of N addition on the drought response of productivity increased as drought duration increased, and these responses were a function of changes in AGB and biomass allocation, particularly root to shoot ratio. However, no significant effects of drought occurred in fertilized or unfertilized plots in the growing season a year after the experiment, N addition did limit the recovery of AGB from severe drought during the remainder of the current growing season. Our results imply that chronic N enrichment could exacerbate the effects of growing-season drought on grassland productivity caused by altered precipitation seasonality under climate change, but that these effects do not carry over to the next growing season.

13.
J Sport Health Sci ; 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34293496

RESUMO

PURPOSE: Balance impairment is one of the strongest risk factors for falls. Proprioception, cutaneous sensitivity, and muscle strength are 3 important contributors to balance control in older adults. The relationship that dynamic and static balance control has to proprioception, cutaneous sensitivity, and muscle strength is still unclear. This study was performed to investigate the relationship these contributors have to dynamic and static balance control. METHODS: A total of 164 older adults (female=89, left dominant = 15, age: 73.5 ± 7.8 years, height: 161.6 ± 7.1 cm, weight: 63.7 ± 8.9 kg) participated in this study. It tested the proprioception of their knee flexion/extension and ankle dorsi/plantarflexion, along with cutaneous sensitivity at the great toe, 1st and 5th metatarsals, arch, and heel, and the muscle strength of their ankle dorsi/plantarflexion and hip abduction. The Berg Balance Scale (BBS) and the root mean square (RMS) of the center of pressure (CoP) were collected as indications of dynamic and static balance control. A partial correlation was used to determine the relationship between the measured outcomes variables (BBS and CoP-RMS) and the proprioception, cutaneous sensitivity, and muscle strength variables. RESULTS: Proprioception of ankle plantarflexion (r = -0.306, p = 0.002) and dorsiflexion (r = -0.217, p = 0.030), and muscle strength of ankle plantarflexion (r = 0.275, p = 0.004), dorsiflexion (r = 0.369, p < 0.001), and hip abduction (r = 0.342, p < 0.001) were weakly to moderately correlated with BBS. Proprioception of ankle dorsiflexion (r = 0.218, p = 0.020) and cutaneous sensitivity at the great toe (r = 0.231, p = 0.041) and arch (r = 0.285, p = 0.023) were weakly correlated with CoP-RMS in the anteroposterior direction. Proprioception of ankle dorsiflexion (r = 0.220, p = 0.035), knee flexion (r = 0.308, p = 0.001) and extension (r = 0.193, p = 0.040), and cutaneous sensitivity at the arch (r = 0.206, p = 0.043) were weakly to moderately correlated with CoP-RMS in the mediolateral direction. CONCLUSION: There is a weak to moderate relationship between proprioception and dynamic and static balance control, a weak relationship between cutaneous sensitivity and static balance control, and a weak to moderate relationship between muscle strength and dynamic balance control.

14.
Eur J Hosp Pharm ; 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34301743

RESUMO

OBJECTIVES: Dabigatran-induced oesophagitis has emerged in recent years. However, the incidence and clinical characteristics of patients with dabigatran-induced oesophagitis have not yet been clarified. The aim of this study was to examine the clinical characteristics of the disease. METHODS: A retrospective analysis was undertaken of the literature on dabigatran-induced oesophagitis in Chinese and English from 2008 onwards. RESULTS: There were 20 men (74.07%) and seven women (25.93%) in the study; their median age was 75 years (range 37-90). The main clinical symptoms were dysphagia (42.31%), odynophagia (26.92%), retrosternal pain (23.08%) and heartburn (23.08%). Endoscopy mainly showed sloughing mucosal casts (14 cases, 56%), ulcers (8 cases, 32%) and erosion (6 cases, 24%). The main injury sites were the mid to lower oesophagus (32%) and the mid oesophagus (32%). Withdrawal of dabigatran or giving the correct medication regimen resulted in rapid recovery of clinical symptoms from 1 day in some patients and up to 4 weeks, and mucosal recovery (2-5 weeks) in a median time of 3 weeks (range 0.29-48) in all patients. CONCLUSIONS: Oesophagitis is a rare complication of dabigatran with a good prognosis. Patients should be given proper medication instructions to prevent the occurrence of dabigatran-induced oesophagitis.

15.
Life Sci ; : 119210, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34243946

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concern has been raised by a reader about both the inappropriateness of certain methods used to prepare Figures 1A and 3A; as well as the lack of important information including the exact age of the mice and details of the ELISA used. These issues could undermine the scientific grounds of the article. Apologies are offered to readers of the journal that this was not detected during the submission process.

16.
Cancer Lett ; 518: 169-179, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34273467

RESUMO

Cervical cancer (CC) patients with lymph node (LN) metastasis often have an extremely poor prognosis. However, the precise molecular mechanisms involved in LN metastasis of CC remain largely unknown. Herein, through RNA screening, we identified a novel long noncoding RNA (lncRNA), LncCCLM, that was downregulated in cervical cancer tissues and closely associated with lymphatic metastasis in cervical cancer patients. Gain-of-function and loss-of-function studies in CC cells demonstrated that LncCCLM inhibited cervical cancer-associated lymphangiogenesis, and CC cell migration and invasion in vitro and suppressed LN metastasis in vivo, but did not affect the growth of CC cells. Mechanistically, LncCCLM localized in the cytoplasm and interacted with staufen double-stranded RNA binding protein 1 (STAU1), promoting the binding of the STAU1 protein to the 3' untranslated region (3'UTR) of insulin-like growth factor 1 (IGF-1) mRNA, which accelerated the degradation of IGF-1 mRNA and decreased the IGF-1 protein level, ultimately reducing lymphangiogenesis and lymphatic metastasis in cervical cancer. Collectively, our findings suggest that LncCCLM acts as a tumor suppressor and may be used as a prognostic biomarker and therapeutic target for clinical intervention in LN-metastatic cervical cancer.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34319483

RESUMO

PURPOSE: Basaloid squamous cell carcinoma (BSCC) is a rare aggressive variant of squamous cell carcinoma (SCC) with a poor prognosis. No large series of exclusively hypopharyngeal BSCC patients have been previously reported. Therefore, this retrospective population-based study aims to explain the patient demographics, clinicopathologic characteristics, incidence, and survival outcomes of hypopharyngeal BSCC and how it relates to conventional-type SCC. METHODS: The National Cancer Institute's Surveillance, Epidemiology, and End Results database registry was queried for patients diagnosed with hypopharyngeal BSCC and conventional-type SCC between 2001 and 2016. RESULTS: The incidence of hypopharyngeal BSCC from 2001 to 2016 was 0.0161 per 100,000 individuals. The BSCC group comprised 213 patients, and the SCC group 7958 patients. The majority of BSCCs were considered high grade (Grade III/IV, 89.58%). Most BSCC patients were diagnosed at an advanced stage (American Joint Committee on Cancer [AJCC] stage IV, 65.38%). The 1-, 5-, and 10-year disease-specific survival (DSS) rates for hypopharyngeal BSCC were 84.10%, 57.40%, and 46.20%, respectively. Multivariate analysis, after adjustment for sex, age, race, tumor location, grade, and AJCC stage, showed that patients with BSCC had significantly better DSS than those with conventional-type SCC. Surgery with radiation contributed to a favorable DSS for BSCC patients in comparison with other treatments. CONCLUSION: This analysis of the largest hypopharyngeal BSCC series indicates a better prognosis for this pathologic type compared with conventional-type hypopharyngeal SCC. Multimodality treatment with surgery and radiation may result in a favorable prognosis for hypopharyngeal BSCC patients.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34319516

RESUMO

Co3O4 is a promising Hg0 removal catalyst for industrial application. Operating temperature and low sulfur resistance are two of the main problems that hinder its industrial application in Hg0 removal. Herein, a metal-organic framework (Co-BDC) was introduced as a sacrificial template to obtain the catalyst nano-sized Co3O4@C by calcination. Part of the organic ligands is carbonized during the calcination. Carbon wrapped Co3O4 and reduced metal agglomeration. The optimal Hg0 removal temperature of the existing cobalt oxide catalysts was always around 150 °C, but H2-TPR showed that the oxygen atoms on the Co3O4@C were more active than those on Co3O4, causing the Hg0 removal temperature window of Co3O4@C to shift to lower temperatures. The Hg0 removal efficiency of Co3O4@C could reach almost 100% even at 25 °C. In the meanwhile, Co3O4@C also showed a strong SO2 resistance at ambient temperature. Experimental results and characterization proved that SO2 did not compete with Hg0 on the surface of Co3O4 at low temperatures. On the contrary, it participated in the oxidation of Hg0. This is a great improvement for Co3O4 catalyst in Hg0 removal. It reduces the restrictions on the application of Co3O4 in Hg0 removal. Co3O4@C shows considerable potential as an Hg0 removal catalyst.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34214636

RESUMO

BACKGROUND: Mitral regurgitation (MR) quantification by proximal isovelocity surface area (PISA) method remains challenging. Using computer models, this study aims to evaluate the accuracy of different PISA methods and quantify their errors. METHODS: Five functional MR (FMR) computer models of different geometric and tethering abnormalities were created, validated and treated as phantom models, from which the reference values were directly obtained. Virtual 2D and 3D PISA (both peak and integrated values) were performed on these phantom models. By comparing virtual PISA results with reference values, the accuracy of different PISA methods was evaluated, and their sources of errors were quantified. RESULTS: Compared to reference values of regurgitant flow rate, excellent correlations were found for true-PISA (r = 0.99, bias 32.3 ± 35.3 ml/s), 3D-PISA (r = 0.97, bias -24.4 ± 55.5 ml/s), followed by multiplane 2D hemicylindrical (HC)-PISA (r = 0.88, bias -24.1 ± 85.4 ml/s), hemiellipsoidal (HE)-PISA (r = 0.91, bias -55.7 ± 96.6 ml/s). Weaker correlations were found for single plane 2D hemispherical (HS)-PISA (PLAX: r = 0.71, bias -77.6 ± 124.5 ml/s; A2Ch: r = 0.69, bias -52.0 ± 122.0 ml/s; A4Ch: r = 0.82, bias -65.5 ± 107.3 ml/s). For regurgitant volume quantification, integrated PISA was more accurate than peak PISA. The bias of 3D PISA improved from -12.7 ± 7.8 ml (peak PISA) to -2.1 ± 5.3 ml (integrated PISA). CONCLUSIONS: For FMR quantification, 2D HS-PISA had significant underestimation, multiplane 2D HE- and HC-PISA showed improve accuracy, while 3D-PISA is the most accurate. PISA method is subject to both systematic underestimation due to Doppler angle effect, and systematic overestimation when regurgitant flow is not perpendicular to PISA contour. Integrated PISA is able to capture the dynamic MR and is therefore more accurate than peak PISA. The sum of regurgitant flow rates is the most feasible way to perform integrated PISA.

20.
Mol Cell Proteomics ; : 100117, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34214668

RESUMO

Glaucoma is the leading cause of irreversible blindness worldwide. The proteome characterization of glaucoma is not clearly understood. A total of 175 subjects, including 57 primary acute angle-closure glaucoma (PAACG), 50 Primary chronic angle-closure glaucoma (PCACG), 35 neovascular glaucoma (NVG) and 33 cataract patients, were enrolled and comparison proteomic analysis was provided. Above samples were randomly divided into discovery group or validation group, whose AH proteome were analyzed by data-independent acquisition method or by parallel reaction monitor method. The common proteome features of three types of glaucoma were immune response, lipid metabolism and cell death. Three proteins, VTN, SERPIND1 and CD14, showed significantly up-regulated in glaucoma, and could discriminate glaucoma from cataract. Mutual differential proteomic analysis of PAACG, PCACG and NVG showed different proteome characterization of the three types of glaucoma. NVG was characterized with activated angiogenesis. PAACG was characterized with activation of inflammation response. SERPIND1 was discovered to play vital role in glaucoma occurrences, which is associated with eye transparency decrease and glucose metabolism. This study would provide insights in understanding proteome characterization of glaucoma and benefit the clinical application of AH proteome.

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