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1.
Carbohydr Polym ; 253: 117198, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278972

RESUMO

Biocompatible polymers and drug-delivery scaffolds have driven development in bone regeneration. In this study, we fabricated a chitosan (CS)-coated polytrimethylene carbonate (PTMC)/polylactic acid (PLLA)/oleic acid-modified hydroxyapatite (OA-HA)/vancomycin hydrochloride (VH) microsphere scaffold for drug release with excellent biocompatibility. The incorporation of PLLA, OA-HA, and VH into PTMC microspheres not only slowed the biodegradability of the scaffold but also enhanced its mechanical properties and surface properties. Moreover, the CS coating stimulated extensive adhesion of osteoblasts before OA-HA incorporation, which facilitated the controlled release of OA-HA. The scaffolds were characterized via scanning electron microscopy, in vitro comprehensive performance testing, cell culturing, and microcomputer tomography scanning. The results indicated that the surface of the composite microsphere scaffold was suitable for osteoblast adhesion. Additionally, the release of OA-HA stimulated osteogenic proliferation. Our findings suggest that the CS-PTMC/PLLA/OA-HA/VH microsphere scaffold is promising for bone tissue engineering applications.

2.
Head Neck ; 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33301222

RESUMO

BACKGROUND: Esthesioneuroblastoma (ENB) is a rare malignant neoplasm. Currently, no consistent and universal staging system for ENB exists. The aim of this study is to propose a TNM-based classification. SUBJECTS AND METHODS: Hundred and forty-two patients from our institution, with ENB pathologically confirmed between July 1978 and December 2018, were reviewed. All patients were restaged according to the Kadish stage, Morita stage and American Joint Committee on Cancer (AJCC) T classification from clinical and radiological data. Multivariate Cox proportional hazard regression analyses were performed to determine the impact of various factors. The goodness-of-fit and predictive accuracy of the different staging systems were calculated using R software. RESULTS: The median follow-up time was 57 months (range: 4-229 months). According to the Kadish system, the 5-year overall survival (OS) for patients with stage A, B and C was 100%, 83.6% and 64.2%, respectively (P = .055). With respect to the Morita classification, 5-year OS for stages A, B, C and D was 100%, 83.6%, 70.7% and 50.0%, respectively (P = .004). Analysis based on the proposed staging model demonstrated 5-year OS for stage I, II, III and IV disease was 100%, 88.9%, 75.9% and 49.0%, respectively (P < .001). In separate multivariate Cox regression models, only the novel staging system exhibited independent effects on OS (P = .004); the Akaike information criterion and Harrell's concordance index were also superior to those calculated for the Kadish or Morita systems. CONCLUSIONS: The proposed TNM-based staging system offers an improved prognostic assessment for patients with ENB. Further verification and refinement from additional dataset application is required.

3.
Ann Transl Med ; 8(19): 1230, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33178762

RESUMO

Background: The global mortality rate for coronavirus disease 2019 (COVID-19) is 3.68%, but the mortality rate for critically ill patients is as high as 50%. Therefore, the exploration of prognostic predictors for patients with COVID-19 is vital for prompt clinical intervention. Our study aims to explore the predictive value of hematological parameters in the prognosis of patients with severe COVID-19. Methods: Ninety-eight patients who were diagnosed with COVID-19 at Jingzhou Central Hospital and Central Hospital of Wuhan, Hubei Province, were included in this study. Results: The median age of the patients was 59 [28-80] years; the median age of patients with a good prognosis was 56 [28-79] years, and the median age of patients with a poor outcome was 67 [35-80] years. The patients in the poor outcome group were older than the patients in the good outcome group (P<0.05). The comparison of hematological parameters showed that lymphocyte count (Lym#), red blood cells (RBCs), hemoglobin (HGB), hematocrit (HCT), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) were significantly lower in the poor outcome group than in the good outcome group (P<0.05). Further, the red cell volume distribution width-CV (RDW-CV) and red cell volume distribution width-SD (RDW-SD) were significantly higher in the poor outcome group than in the good outcome group (P<0.0001). Receiver operating characteristic (ROC) curves showed RDW-SD, with an area under the ROC curve (AUC) of 0.870 [95% confidence interval (CI) 0.796-0.943], was the most significant single parameter for predicting the prognosis of severe patients. When the cut-off value was 42.15, the sensitivity and specificity of RDW-SD for predicting the prognosis of severe patients were 73.1% and 80.2%, respectively. Reticulocyte (RET) channel results showed the RET level was significantly higher in critical patients than in moderate patients and severe patients (P<0.05), which may be one cause of the elevated RDW in patients with a poor outcome. Conclusions: In this study, the hematological parameters of COVID-19 patients were statistically analyzed. RDW was found to be a prognostic predictor for patients with severe COVID-19, and the increase in RET may contribute to elevated RDW.

4.
Cancer Manag Res ; 12: 11563-11571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33209060

RESUMO

Objective: To investigate the clinical outcomes of hypofractionated radiotherapy for adrenal metastases. Materials and Methods: We retrospectively reviewed patients diagnosed with adrenal metastases and treated with hypofractionated radiotherapy, who did not receive adrenalectomy or have disease progression after chemotherapy, from 2007 to 2019. The Kaplan-Meier method was used to estimate local control rate (LCR), progression-free survival (PFS), and overall survival (OS). Univariate analysis was performed using Log rank test. Results: Thirty-five patients with 42 lesions were enrolled, and the lung was the most common primary site (80.0%). The median follow-up time was 46.4 months. The median volume of GTV and PTV was 23.2 cm3 (range: 3.5-97.8 cm3) and 38.3 cm3 (range: 10.2-135.6 cm3), respectively. The main dose regimens were 60 Gy delivered in 4-15 fractions, with the median dose of PTV being 60 Gy (range: 40-66.3 Gy) and the biologically effective dose (BED) being 84 Gy (range: 56-110 Gy). The 1-year and 2-year LCR, OS, and PFS were 92.7% and 88.1%, 76.9% and 45.4%, and 25.1% and 14.4%, respectively. Univariate analysis showed that chemotherapy, disease-free interval from primary disease diagnosis to adrenal metastases diagnosis, and age were significant factors for LCR, OS, and PFS, respectively (p=0.017, 0.049, and 0.004, respectively). No more than grade III toxicities were observed. Conclusion: As a non-invasive approach, hypofractionated radiotherapy is safe and effective for metastatic adrenal lesions, without serious complications.

5.
Adv Mater ; : e2005113, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33251649

RESUMO

Sn-based materials are identified as promising catalysts for the CO2 electroreduction (CO2RR) to formate (HCOO- ). However, their insufficient selectivity and activity remain grand challenges. A new type of SnO2 nanosheet with simultaneous N dopants and oxygen vacancies (VO -rich N-SnO2 NS) for promoting CO2 conversion to HCOO- is reported. Due to the likely synergistic effect of N dopant and VO , the VO -rich N-SnO2 NS exhibits high catalytic selectivity featured by an HCOO- Faradaic efficiency (FE) of 83% at -0.9 V and an FE of > 90% for all C1 products (HCOO- and CO) at a wide potential range from -0.9 to -1.2 V. Low coordination Sn-N moieties are the active sites with optimal electronic and geometric structures regulated by VO and N dopants. Theoretical calculations elucidate that the reaction free energy of HCOO* protonation is decreased on the VO -rich N-SnO2 NS, thus enhancing HCOO- selectivity. The weakened H* adsorption energy also inhibits the hydrogen evolution reaction, a dominant side reaction during the CO2RR. Furthermore, using the catalyst as the cathode, a spontaneous Galvanic Zn-CO2 cell and a solar-powered electrolysis process successfully demonstrated the efficient HCOO- generation through CO2 conversion and storage.

6.
J Am Chem Soc ; 142(38): 16429-16436, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32862644

RESUMO

Nonoxidative dehydrogenation is promising for production of light olefins from shale gas, but current technology relies on precious Pt or toxic Cr catalysts and suffers from thermodynamically oriented coke formation. To solve these issues, the earth-abundant iron catalyst is employed, where Fe species are effectively modulated by siliceous zeolite, which is realized by the synthesis of Fe-containing MFI siliceous zeolite in the presence of ethylenediaminetetraacetic sodium (FeS-1-EDTA). Catalytic tests in ethane dehydrogenation show that this catalyst has a superior coke resistance in a 200 h run without any deactivation with extremely high activity and selectivity (e.g., 26.3% conversion and over 97.5% selectivity to ethene in at 873 K, close to the thermodynamic equilibrium limitation). Multiple characterizations demonstrate that the catalyst has uniformly and stably isolated Fe sites, which improves ethane dehydrogenation to facilitate the fast desorption of hydrogen and olefin products in the zeolite micropores and hinders the coke formation, as also identified by density functional calculations.

7.
Angew Chem Int Ed Engl ; 59(50): 22408-22413, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32886835

RESUMO

Developing copper-free catalysts for CO2 conversion into hydrocarbons and oxygenates is highly desirable for electrochemical CO2 reduction reaction (CO2 RR). Herein, we report a cobalt phthalocyanine (CoPc) and zinc-nitrogen-carbon (Zn-N-C) tandem catalyst for CO2 RR to CH4 . This tandem catalyst shows a more than 100 times enhancement of the CH4 /CO production rate ratio compared with CoPc or Zn-N-C alone. Density functional theory (DFT) calculations and electrochemical CO reduction reaction results suggest that CO2 is first reduced into CO over CoPc and then CO diffuses onto Zn-N-C for further conversion into CH4 over Zn-N4 site, decoupling complicated CO2 RR pathway on single active site into a two-step tandem reaction. Moreover, mechanistic analysis indicates that CoPc not only generates CO but also enhances the availability of *H over adjacent N sites in Zn-N4 , which is the key to achieve the high CH4 production rate and understand the intriguing electrocatalytic behavior which is distinctive to copper-based tandem catalysts.

8.
Cancer Manag Res ; 12: 8581-8587, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982450

RESUMO

Background: This study was to determine the patterns of regional lymph node (LN) spread and the risk factors of retropharyngeal lymph node (RPLN) metastasis based on magnetic resonance imaging (MRI) in hypopharyngeal squamous carcinoma (HPC) to improve clinical target volume (CTV) delineation. Methods: A cohort of 326 consecutive patients of HPC in a single institute were retrospectively reviewed. All patients underwent MRI prior to initial treatment, and the diagnosis based on MRI of the LN metastasis was confirmed by all radiation oncologists in the head and neck group during twice weekly chat rounds. Statistical analysis of data was using chi-square test and multivariant logistic regression model in SPSS 22.0 software. Results: The LN metastasis rate of all patients in this cohort was 90.5% (295/326). Level IIa/b and level III were the most frequently involved regions followed by level IV and retropharyngeal region. Skip metastasis only occurred in 6.4% (19/295). Univariate and multivariate analysis demonstrated that primary tumor subsites were located in the posterior pharyngeal wall (P=0.002), bilateral cervical LN metastasis (P=0.020), larger volume of primary gross target (GTVp, P=0.003), and larger volume of LN gross target (GTVnd, P=0.023) were significantly associated with RPLN metastasis. Conclusion: The regional LN spread of HPC follows an ordered pattern as level II is the most frequently involved area followed by level III, level IV, and RPLN. RPLN metastasis is more likely to occur in patients with primary site of posterior pharyngeal wall, large tumor burden, or bilateral neck LN metastasis. Therefore, it is highly recommended that the RPLN should be included into CTV for patients who have these risk factors.

9.
J Am Chem Soc ; 142(40): 17167-17174, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32924478

RESUMO

Encapsulation of metal nanocatalysts by support-derived materials is well known as a classical strong metal-support interaction (SMSI) effect that occurs almost exclusively with active oxide supports and often blocks metal-catalyzed surface reactions. In the present work this classical SMSI process has been surprisingly observed between metal nanoparticles, e.g., Ni, Fe, Co, and Ru, and inert hexagonal boron nitride (h-BN) nanosheets. We find that weak oxidizing gases such as CO2 and H2O induce the encapsulation of nickel (Ni) nanoparticles by ultrathin boron oxide (BOx) overlayers derived from the h-BN support (Ni@BOx/h-BN) during the dry reforming of methane (DRM) reaction. In-situ surface characterization and theory calculations reveal that surface B-O and B-OH sites in the formed BOx encapsulation overlayers work synergistically with surface Ni sites to promote the DRM process rather than blocking the surface reactions.

10.
Radiat Oncol ; 15(1): 219, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948223

RESUMO

BACKGROUND: The aim of this study is to evaluate the efficacy of different treatment strategies and the potential prognostic factors of esthesioneuroblastoma (ENB). MATERIALS AND METHODS: Between April 1984 and December 2018, 138 patients with non-metastatic ENB were retrospectively analyzed. The treatment modalities mainly included surgery alone (n = 7), radiotherapy alone (n = 33), concurrent chemoradiotherapy (n = 17), surgery combined with current chemoradiotherapy (n = 32), and surgery plus radiotherapy (n = 49). RESULTS: The median follow-up time for the entire cohort was 61 months (range, 4-231 months). The 5-year overall survival (OS), locoregional failure-free survival (LRFFS), and distant metastasis-free survival (DMFS) rate were 69.6, 78.0 and 73.9%, respectively. Surgery combined with radiotherapy elicited superior survival results, and the combination of surgery and current chemoradiotherapy achieved the best prognoses for all patients, patients with advanced Kadish disease, patients receiving intensity modulated radiation therapy and those with positive surgical margin. Univariate analysis identified orbital invasion and treatment modalities were predictors for OS, LRFFS and DMFS. Lymph node metastasis was associated with OS and DMFS, but not LRFFS. Intracranial invasion, advanced Kadish stage and not receiving concurrent chemotherapy were also predictive of lower OS. Multivariate analyses indicated that lymph node metastasis was an independent prognostic factor affecting DMFS, whereas treatment modalities was independent prognostic factors for OS and LRFFS. CONCLUSION: Orbital invasion, intracranial invasion, lymph node metastasis and advanced Kadish disease at initial diagnosis were significantly associated with inferior prognosis. Regarding the treatment modality, the optimal strategy remined surgery with radiotherapy-based multimodality treatment. The concurrent chemoradiotherapy may play a more beneficial role.

11.
Front Oncol ; 10: 1314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850414

RESUMO

Purpose: To explore the efficacy of concomitant chemotherapy in intensity-modulated radiotherapy (IMRT) to treat stage II nasopharyngeal carcinoma (NPC). Methods and Materials: In this randomized phase 2 study [registered with ClinicalTrials.gov (NCT01187238)], eligible patients with stage II (2010 UICC/AJCC) NPC were randomly assigned to either IMRT alone (RT group) or IMRT combined with concurrent cisplatin (40 mg/m2, weekly) (CCRT group). The primary endpoint was overall survival (OS). The second endpoints included local failure-free survival (LFFS), regional failure-free survival (RFFS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and acute toxicities. Results: Between May 2010 to July 2012, 84 patients who met the criteria were randomized to the RT group (n = 43) or the CCRT group (n = 41). The median follow-up time was 75 months. The OS, LFFS, RFFS, DFS, and DMFS for the RT group and CCRT group were 100% vs. 94.0% (p = 0.25), 93.0% vs. 89.3% (p = 0.79), 97.7% vs. 95.1% (p = 0.54), 90.4% vs. 86.6% (p = 0.72), and 95.2% vs. 94.5% (p = 0.77), respectively. A total of 14 patients experienced disease failure, 7 patients in each group. The incidence of grade 2 to 4 leukopenia was higher in the CCRT group (p = 0.022). No significant differences in liver, renal, skin, or mucosal toxicity was observed between the two groups. Conclusion: For patients with stage II NPC, concomitant chemotherapy with IMRT did not improve survival or disease control but had a detrimental effect on bone marrow function.

12.
Oral Oncol ; 111: 104923, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32795912

RESUMO

OBJECTIVE: This study is aimed to evaluate the long-term outcomes and management approaches in different histological subtypes of primary nasopharyngeal adenocarcinoma (NPAC). MATERIALS AND METHODS: 71 patients with NPAC at our institution between 1984 and 2016 were reviewed, including adenoid cystic carcinoma (ACC) in 43 patients, mucoepidermoid carcinoma (MEC) in 17 patients, and primary traditional adenocarcinoma (AC) in 11 patients. 37 patients received primary radiotherapy and 34 patients underwent primary surgery. RESULTS: The median time of follow-up was 77 months. The 5-year overall survival rate (OS), locoregional failure-free survival rate (LRFFS) and distant metastasis failure-free survival rate (DFFS) were 69.9%, 67.1% and 77.9%, respectively. Patients who received combined modality therapy had better 5-year OS (73.7% vs 66.2%, p = 0.065) and LRFFS (73.1% vs 64.5%, p = 0.047) than patients receiving single modality therapy. Regarding the different histological subtypes, the survival rates of patients with ACC undergoing primary radiotherapy and primary surgery were similar (5-year OS 82.3% vs 68.8%, LRFFS 70.0% vs 70.8%, p>0.05). As to patients with MEC and AC, those who underwent primary surgery achieved better 5-year OS (75.6% vs 45.5%, p = 0.001) and LRFFS (70.6%% vs 57.1%, p = 0.014) than those who received primary radiotherapy. Multivariate analyses indicated that histological subtypes and radiotherapy technique were independent factors for OS. CONCLUSIONS: The optimal treatment policy for NPAC remained the combination of radiotherapy and surgery. For patients with ACC, radiotherapy could be considered as the primary treatment. Surgery was suggested to be the primary treatment in patients with MEC and AC.

13.
Nat Commun ; 11(1): 3415, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641692

RESUMO

For most metal-containing CO2 reduction reaction (CO2RR) electrocatalysts, the unavoidable self-reduction to zero-valence metal will promote hydrogen evolution, hence lowering the CO2RR selectivity. Thus it is challenging to design a stable phase with resistance to electrochemical self-reduction as well as high CO2RR activity. Herein, we report a scenario to develop hydrocerussite as a stable and active electrocatalyst via in situ conversion of a complex precursor, tannin-lead(II) (TA-Pb) complex. A comprehensive characterization reveals the in situ transformation of TA-Pb to cerussite (PbCO3), and sequentially to hydrocerussite (Pb3(CO3)2(OH)2), which finally serves as a stable and active phase under CO2RR condition. Both experiments and theoretical calculations confirm the high activity and selectivity over hydrocerussite. This work not only offers a new approach of enhancing the selectivity in CO2RR by suppressing the self-reduction of electrode materials, but also provides a strategy for studying the reaction mechanism and active phases of electrocatalysts.

14.
Colloids Surf B Biointerfaces ; 195: 111218, 2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32650218

RESUMO

Poly (lactic acid) (PLA), although extensively used as biomedical materials, has the distinct disadvantage of producing acidic byproducts which can lead to tissue inflammatory reactions and clinic failure. Here we presented a combination of Poly (lactic acid-co-trimethylene carbonate) and natural polymer chitosan, improving its compression resilience and reducing its acidic byproducts. In this case, we developed 3D scaffolds using solvent/nonsolvent technique sintered PLA-TMC and PLA-TMC/Chitosan microspheres with selected particle size (355-500 µm). By controlling the preparation methods and parameters, the porosity, pore size and mechanical properties of microsphere scaffolds can be designed and controlled. Strikingly, PLA-TMC/15 % Chitosan microsphere scaffolds possess shape-memory effect and rapidly recovered to initial shape when heated to 37℃ within 300 s. The microsphere scaffolds had a 3D porous architecture with pore size ranging from 105.67 ± 12.51 µm to 129.69 ± 11.39 µm. The mechanical and physicochemical properties of microspheres and scaffolds were characterized in details. Moreover, all microsphere scaffolds were qualified as their compressive modulus (120.36 MPa -195.32 MPa) matched the cancellous bone during 16 weeks degradation. Furthermore, CCK8 cell proliferation assay and ALP activity assay verified that the scaffolds were non-toxic and conductive to cell adhesion. The scaffolds are expected to be used in bone regeneration and bone repair field.

15.
Ann Transl Med ; 8(9): 593, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32566620

RESUMO

Background: The third fatal coronavirus is the novel coronavirus (SARS-CoV-2) that causes novel coronavirus pneumonia (COVID-19) which first broke out in December 2019. Patients will develop rapidly if there is no any intervention, so the risk identification of severe patients is critical. The aim of this study was to investigate the characteristics and rules of hematology changes in patients with COVID-19, and to explore the possibility differentiating moderate and severe patients using conventional hematology parameters or combined parameters. Methods: The clinical data of 45 moderate and severe type patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in Jingzhou Central Hospital from January 23 to February 13, 2020 were collected. The epidemiological indexes, clinical symptoms, and laboratory test results of the patients were retrospectively analyzed. Those parameters with significant differences between moderate and severe cases were analyzed, and the combination parameters with the best diagnostic performance were selected using the linear discriminant analysis (LDA) method. Results: Of the 45 patients with the novel 2019 corona virus (COVID-19) (35 moderate and 10 severe cases), 23 were male and 22 were female, with ages ranging from 16 to 62 years. The most common clinical symptoms were fever (89%) and dry cough (60%). As the disease progressed, white blood cell count (WBC), neutrophil count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), red blood cell distribution width-coefficient of variation (RDW-CV), and red cell volume distribution width-standard deviation (RDW-SD) parameters in the severe group were significantly higher than those in the moderate group (P<0.05); meanwhile, lymphocyte count (Lym#), eosinophil count (Eos#), high fluorescent cell percentage (HFC%), red blood cell count (RBC), hemoglobin (HGB), and hematocrit (HCT) parameters in the severe group were significantly lower than those in the moderate group (P<0.05). For NLR parameter, it's area under the curve (AUC), cutoff, sensitivity and specificity were 0.890, 13.39, 83.3% and 82.4% respectively; meanwhile, for PLR parameter, it's AUC, cutoff, sensitivity and specificity were 0.842, 267.03, 83.3% and 74.0% respectively. The combined parameters of NLR and RDW-SD had the best diagnostic efficiency (AUC =0.938), and when the cutoff value was 1.046, the sensitivity and the specificity were 90.0% and 84.7% respectively, followed by the combined parameter NLR&RDW-CV (AUC =0.923). When the cut-off value was 0.62, the sensitivity and the specificity for distinguishing severe type from moderate cases of COVID-19 were 90.0% and 82.4% respectively. Conclusions: The combined NLR and RDW-SD parameter is the best hematology index. It may help clinicians to predict the severity of COVID-19 patients and can be used as a useful indicator to help prevent and control the epidemic.

16.
Int J Clin Exp Pathol ; 13(4): 635-641, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32355511

RESUMO

OBJECTIVE: This study aimed to evaluate the dental-pulp status in patients with chronic advanced periodontitis. MATERIALS AND METHODS: Sixty teeth were extracted from patients with advanced periodontitis. Before extraction, electric pulp tests were conducted to explore the real state of the pulp. According to the height of the residual periodontal membrane, all teeth were divided into two groups: group 1< (3 mm) and group 2 (3-6 mm). Two groups of teeth were sliced and stained with hematoxylin and eosin. The dental-pulp status of histopathologic changes was analyzed. RESULTS: The frequency of pulp necrosis in group 1 was significantly higher than that in group 2 (P<0.05). The frequency of a complete odontoblastic layer, vacuolar degeneration of the odontoblastic layer, pulp edema, and reticular atrophy in group 1 were significantly lower than in group 2 (P<0.05). There were no significant differences in other histopathologic changes. Histopathologic examination compared to the traditional electric pulp testing, revealed that 24.48% of dental pulps showed complete pulp necrosis and 5.75% exhibited normal pulp tissue by histopathology. However, only 9.52% of teeth exhibited no response, and 33.33% displayed responses similar to those of neighboring teeth, suggesting that the electric pulp test cannot completely detect dental-pulp status. CONCLUSIONS: Teeth in patients with chronic advanced periodontitis, exhibited worse pulp conditions with decreased height of the residual periodontal membrane. The results of electric pulp testing were not completely representative of histopathologic results in advanced periodontitis.

17.
Int Urol Nephrol ; 52(6): 1093-1101, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32297182

RESUMO

OBJECTIVE: The evidence from epidemiological research on whether the efficacy of rituximab in treatment of refractory nephrotic syndrome (NS) is better than other agents is inconsistent. This meta-analysis aimed to assess the efficacy of rituximab in the treatment of NS compared with other immunosuppressive agents. METHODS: Relevant literatures were identified and evaluated for quality before October 2019 through multiple search strategies on PubMed and EMBASE. Statistical evidence of the symmetry of the funnel plot obtained from Begg's test was indicated by Egger's linear regression and a sensitivity analysis identified heterogeneity. A fixed- or a random-effects model was applied to calculate the pooled SMDs and RRs. RESULTS: A total of 12 studies, involving 383 patients and 354 controls, were included. Compared with other agents, rituximab significantly improved complete remission both in children and adults [Overall: RR = 1.313, 95% CI = 1.170-1.475, P < 0.001; Adult: RR = 1.359, 95% CI = 1.053-1.753, P = 0.019 Children: RR = 1.354, 95% CI = 1.072-1.709, P < 0.001], and dramatically decreased the relapse rate in children [Overall: RR = 0.349, 95% CI = 0.166-0.732, P < 0.001; Children: RR = 0.286, 95% CI = 0.176-0.463, P < 0.001]. CONCLUSIONS: Rituximab might be a promising treatment for refractory NS. Compared with other agents, rituximab significantly improves the complete remission and decreased the relapse rate. However, to confirm the efficacy of rituximab in the treatment of refractory NS, more high-quality, large sample, and multicenter randomized controlled trials are needed.

18.
Exp Ther Med ; 19(4): 2505-2510, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32256728

RESUMO

Fetal chromosomal abnormalities are a common cause of spontaneous abortion. The present study investigated the association between fetal chromosomal abnormalities and the frequency of spontaneous abortions to enable clinicians to provide more informed genetic counseling. A total of 182 patients with a history of spontaneous abortions were recruited from July 2015 to August 2017. G-banding cytogenetic analysis and novel high-throughput ligation-dependent probe amplification (HLPA) techniques were performed on conception in all 182 patients to detect chromosomal abnormalities. Low-coverage whole-genome sequencing (WGS) was performed in 74 patients to detect copy number variations (CNVs). There were no significant differences in the incidence of karyotype abnormalities between patients with sporadic miscarriages (48.0%; SM group) and patients suffering recurrent spontaneous abortions (44.8%; RSA group). The maternal age was markedly higher in patients with 3 miscarriages. WGS indicated that the incidence of pathogenic CNVs in the RSA group was higher than that in the SM group, but the difference was not significant. In conclusion, a high incidence of karyotype abnormalities and pathogenic CNVs was observed in patients with spontaneous abortion. However, no association between fetal chromosomal abnormalities and the number of spontaneous abortions was observed. HLPA assays may be used as an alternative method for fetal karyotype analysis and determination of CNVs in patients with SM and RSA.

19.
Angew Chem Int Ed Engl ; 59(24): 9711-9718, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32189423

RESUMO

NO removal from exhausted gas is necessary owing to its damage to environment. Meanwhile, the electrochemical ammonia synthesis (EAS) from N2 suffers from low reaction rate and Faradaic efficiency (FE). Now, an alternative route for ammonia synthesis is proposed from exhaust NO via electrocatalysis. DFT calculations indicate electrochemical NO reduction (NORR) is more active than N2 reduction (NRR). Via a descriptor-based approach, Cu was screened out to be the most active transition metal catalyst for NORR to NH3 owing to its moderate reactivity. Kinetic barrier calculations reveal NH3 is the most preferred product relative to H2 , N2 O, and N2 on Cu. Experimentally, a record-high EAS rate of 517.1 µmol cm-2 h-1 and FE of 93.5 % were achieved at -0.9 V vs. RHE using a Cu foam electrode, exhibiting stable electrocatalytic performances with a 100 h run. This work provides an alternative strategy to EAS from exhaust NO, coupled with NO removal.

20.
Phys Chem Chem Phys ; 22(9): 5293-5300, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32096531

RESUMO

Transition metals and zeolites are extremely different catalysts used for methanol conversion. Zeolites are able to catalyze methanol conversion to hydrocarbons like gasoline and olefins, while transition metals show the selectivity of syngas. It is quite important to establish a general description from a catalysis point of view for a variety of catalysts. In this work, we have employed density functional theory calculations to correlate adsorption energies for all intermediates over a set of transition metals and zeolites. We have successfully unveiled the difference in chemical reactivity and catalytic activity for zeolites and transition metals; a comparative description has been finally established between the acidity (and porous effects) of zeolites and electronic (and geometrical) effects over transition metals. The hydrogen adsorption strength was suggested to be a general descriptor for both transition metal and zeolite catalysts. In addition, it was found that some zeolites with the same ammonia adsorption strength, which was always used to describe the acidity in experimental studies, are likely to have different theoretical acidity (hydrogen bonding strength). This eventually opens one more dimension for rational selection and design of zeolites for catalysis application.

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