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1.
Sci Rep ; 10(1): 2367, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047235

RESUMO

The effect of donor-specific anti-human leukocyte antigen (HLA) antibodies (DSAs) has been recognized as a factor in graft failure (GF) in patients who underwent umbilical cord blood transplantation (UBT), matched unrelated donor transplantation (MUDT), or haploidentical stem cell transplantation (haplo-SCT). Presently, we know little about the prevalence of and risk factors for having anti-HLA antibodies among older transplant candidates. Therefore, we analyzed 273 older patients with hematologic disease who were waiting for haplo-SCT. Among all patients, 73 (26.7%) patients had a positive panel-reactive antibody (PRA) result for class I, 38 (13.9%) for class II, and 32 (11.7%) for both. Multivariate analysis showed that females were at a higher risk for having a PRA result for class II (P = 0.001) and for having antibodies against HLA-C and HLA-DQ. Prior pregnancy was a risk factor for having a PRA result for class I (P < 0.001) and for having antibodies against HLA-A, HLA-B and HLA-DQ. Platelet transfusions were risk factors for the following: having a positive PRA result for class I (P = 0.014) and class II (P < 0.001); having antibodies against HLA-A, HLA-B, HLA-C, HLA-DP, HLA-DQ, and HLA-DR; and having higher mean fluorescence intensity (MFI) of PRA for class I (P = 0.042). In addition, previous total transfusions were at high risk for having higher numbers of antibodies to specific HLA loci (P = 0.005), and disease course (7.5 months or more) (P = 0.020) were related to higher MFI of PRAs for class I. Our findings indicated that female sex, prior pregnancy, platelet transfusions and disease courses are independent risk factors for older patients with hematologic disease for having anti-HLA antibodies, which could guide anti-HLA antibody monitoring and be helpful for donor selection.

2.
Respir Physiol Neurobiol ; 274: 103367, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31911201

RESUMO

PURPOSE: Hypoxemia limits exercise in some patients with interstitial lung disease (ILD). High levels of supplemental oxygen during exercise might allow physical training at a higher level and more effective pulmonary rehabilitation (PR). Our goals were to use graded cardiopulmonary exercise testing (CPET) to determine whether hyperoxia (FIO2≈1.0) increased exercise tolerance in patients with mild to moderate ILD. METHODS: We studied 6 patients with ILD, including idiopathic pulmonary fibrosis (IPF) and nonspecific interstitial pneumonia (NSIP). The study population included 3 females and 3 males (age 69 ± 5 [SD] years; FVC 61 ± 14 %; absolute DLCO 53 ± 19 %). Subjects underwent 2 ramped (15 W/min) CPET protocols on a cycle ergometer (Jaeger Oxycon Pro™, CareFusion Respiratory Care) breathing either air or oxygen (FIO2≈1.0) from a Douglas bag in random order. RESULTS: Minute ventilation (VE) increased significantly during CPET breathing air (pre CPET, 18 ± 2 [SEM] L/min; post CPET, 47 ± 6; P = 0.01), but it did not increase significantly breathing oxygen (pre CPET, 15 ± 3 [SEM]; post CPET, 29 ± 9; P = 0.06). Likewise, carbon dioxide production (VCO2) increased significantly during CPET breathing air (pre CPET, 450 ± 93 [SEM] mL/min; post CPET, 1311 ± 200; P = 0.01), but it did not increase significantly breathing oxygen (pre CPET, 369 ± 129; post CPET, 847 ± 832; P = 0.09). Exercise time during CPET did not differ significantly (P = 0.34) in air (5.6 ± 0.9 [SEM] min) or oxygen (7.0 ± 1.8). Increases in heart rate (HR) and Borg dyspnea index (BDI) after CPET were not affected by breathing oxygen. CONCLUSION: Exercise-induced increases in VE and VCO2 were prevented by breathing pure oxygen during CPET, demonstrating both decreased ventilatory drive and more efficient exercise at achieved workloads. Hyperoxia could enhance the ability of patients with ILD to train at higher workloads, resulting in more effective rehabilitation.

3.
Chem Commun (Camb) ; 56(10): 1497-1500, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31915758

RESUMO

The direct photocatalyzed para-selective CAr-H difluoroalkylation of aromatic aldehyde derivatives has been accomplished using a newly explored catalytic system. In addition, when using para-substituted benzaldehydes as substrates, ortho-selective CAr-H difluoroalkylation was also accomplished. It is worth noting that all the above site-selectivity is opposite to traditional Friedel-Crafts reactions of aromatic aldehydes. The preliminary mechanistic investigations indicate that an electrophilic difluoroalkyl radical is involved in the catalytic cycle.

4.
Anal Chem ; 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31961668

RESUMO

In the range of miniature mass spectrometers, the miniature ion trap mass spectrometer with continuous atmospheric pressure interface (CAPI) shows good performance potential and advantages due to its excellent sensitivity and analysis speed. However, in previous cases, placing the ion trap directly near the skimmer aperture means it will suffer high gas shock, which may affect performance. In this study, an improved miniature CAPI ion trap mass spectrometer was developed by gas flow optimization. According to the experimental results, excessive gas flow affects stability and resolution. The impact of the gas flow can be effectively reduced by reducing the inner diameter of the skimmer and adding an additional lens element to move the ion trap away from the skimmer aperture. However, this method will affect the sensitivity of the instrument to some extent, so a discontinuous subatmospheric pressure interface (DSPI) was developed to reduce the gas flow effects and improve the comprehensive performance. When using the DSPI system with a 0.4 mm skimmer and entrance lens, the resolution for roxithromycin was up to 2800 at a scanning speed of 1015 Th/s, which was 3.4-fold higher that without DSPI. The dynamic range of concentration reached 4 orders of magnitude and the detection limit for repaglinide was as low as 1 ng/mL. This study offers a new approach to develop better miniature ion trap mass spectrometers and to extend their practical application.

5.
CPT Pharmacometrics Syst Pharmacol ; 9(2): 87-95, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31919989

RESUMO

We describe a parametric time-to-event model for idiopathic pulmonary fibrosis (IPF) exacerbations and identify predictors of exacerbation risk using data obtained for the tyrosine-kinase inhibitor nintedanib in two phase III studies (INPULSIS-1/2). Parametric survival analysis was performed on time to first exacerbation (censoring on day 372), with univariate analysis to select statistically significant covariates (P = 0.05). Multivariate covariate models were developed using stepwise covariate modeling with forward inclusion (P = 0.05) and backward elimination (P = 0.01). Sixty-three first exacerbation events were reported across 1,061 subjects in the INPULSIS studies. Baseline and decline of forced vital capacity (FVC)/percent-predicted FVC (%pFVC), supplemental oxygen use, baseline CO diffusing capacity and age were statistically significant in the univariate analysis. The final covariate model included decline in FVC to week 52, baseline %pFVC, supplemental oxygen use, and age. The developed model may be used to identify patients at high risk of IPF exacerbations and accelerate development of novel treatments.

6.
Sensors (Basel) ; 20(3)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979353

RESUMO

When performing the inspection of subway tunnels, there is an immense amount of data to be collected and the time available for inspection is short; however, the requirement for inspection accuracy is high. In this study, a mobile laser scanning system (MLSS) was used for the inspection of subway tunnels, and the key technology of the positioning and orientation system (POS) was investigated. We utilized the inertial measurement unit (IMU) and the odometer as the core sensors of the POS. The initial attitude of the MLSS was obtained by using a static initial alignment method. Considering that there is no global navigation satellite system (GNSS) signal in a subway, the forward and backward dead reckoning (DR) algorithm was used to calculate the positions and attitudes of the MLSS from any starting point in two directions. While the MLSS passed by the control points distributed on both sides of the track, the local coordinates of the control points were transmitted to the center of the MLSS by using the ranging information of the laser scanner. Then, a four-parameter transformation method was used to correct the error of the POS and transform the 3-D state information of the MLSS from a navigation coordinate system (NCS) to a local coordinate system (LCS). This method can completely eliminate a MLSS's dependence on GNSS signals, and the obtained positioning and attitude information can be used for point cloud data fusion to directly obtain the coordinates in the LCS. In a tunnel of the Beijing-Zhangjiakou high-speed railway, when the distance interval of the control points used for correction was 120 m, the accuracy of the 3-D coordinates of the point clouds was 8 mm, and the experiment also showed that it takes less than 4 h to complete all the inspection work for a 5-6 km long tunnel. Further, the results from the inspection work of Wuhan subway lines showed that when the distance intervals of the control points used for correction were 60 m, 120 m, 240 m, and 480 m, the accuracies of the 3-D coordinates of the point clouds in the local coordinate system were 4 mm, 6 mm, 7 mm, and 8 mm, respectively.

7.
J Investig Med ; 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980540

RESUMO

OBJECTIVE: To analyze the maternal and fetal factors affecting emergency cesarean section (EmCS) and establish a risk scoring system to quantitatively predict the risk of EmCS. DESIGN: A total of 10,295 pregnant women were enrolled in this study. The influence of maternal and fetal factors on the risk of EmCS was analyzed. RESULTS: 991 (9.63%) cases of failed vaginal delivery received EmCS. The two main causes of EmCS were fetal distress (67.21%) and abnormal fetal position (14.93%). There were significant differences in 17 maternal and fetal factors between the normal vaginal delivery (NVD) and EmCS groups (p<0.05 for all). Univariate and multivariate regression analyses showed that nine maternal and infant factors were independent risk factors (p<0.05 for all). The major factors were abnormal quantity of amniotic fluid (OR 6.867, 95% CI 4.442 to 10.618), nulliparous (OR 4.336, 95% CI 3.074 to 6.115), induction of labor (OR 5.300, 95% CI 4.514 to 6.224) and abnormal characters of amniotic fluid (OR 3.126, 95% CI 2.708 to 3.608). A risk scoring system (six grades) was established based on those factors which showed high discriminative power. The rate of EmCS was 1.30%, 2.57%, 5.83%, 13.94%, 21.75% and 39.71% in grades 1, 2, 3, 4, 5 and 6, respectively. The area under the curve of the risk scoring system was 0.787, indicating that the regression model of the risk factors had a good predictive ability. CONCLUSION: An effective risk scoring system has been developed to quantitatively assess the risk of EmCS based on measurable maternal and fetal factors. The system is simple, easy to operate and has good repeatability in clinical practice.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31932654

RESUMO

The impact of ABO incompatibility on transplantation outcomes in severe aplastic anemia (SAA) patients receiving haploidentical hematopoietic stem cell transplantation (HSCT) remains controversial without published data. A total of 199 SAA patients receiving haploidentical HSCT from ABO-matched (n = 114), minor ABO-incompatible (n = 47), or major ABO-incompatible donors (n = 38) were included in this study. The median time and cumulative incidences of both myeloid and platelet engraftment in the ABO-compatible and ABO-incompatible groups were similar, and pure red cell aplasia was absent. Minor ABO incompatibility increased the rate of grade III-IV acute graft-versus-host disease (aGVHD) (ABO compatible: 6.14 ± 0.05%, minor incompatible: 19.15 ± 0.34%, and major incompatible: 10.53 ± 0.25%; P = 0.051), but did not influence the rates of grade II-IV aGVHD or chronic GVHD (cGVHD). Minor ABO-incompatibility was identified as an independent risk factor for grade III-IV aGVHD by multivariate analysis (hazard ration (HR) = 4.00 (1.48-10.80), P = 0.006). Chronic GVHD, mortality, and treatment failure were not increased in the minor ABO-incompatible group. For SAA patients receiving haploidentical HSCT, ABO compatible donors are better than ABO minor incompatible donors if several haploidentical donors are available.

9.
Biol Blood Marrow Transplant ; 26(2): 351-357, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31704470

RESUMO

Basiliximab has been used successfully as a second-line treatment for steroid-refractory (SR) acute graft-versus-host disease (aGVHD) in adult patients after haploidentical hematopoietic stem cell transplant (haplo-HSCT) but has not been studied separately in the pediatric setting. We retrospectively reviewed 100 pediatric patients after haplo-HSCT receiving basiliximab for grades II (57%), III (27%), and IV (16%) SR aGVHD between January 2015 and December 2017. The median number of basiliximab doses was 4 (range, 2 to 9). The day 28 overall response rate was 85%, with complete response in 74% of patients, partial response in 11% of patients, and no response in 15% of patients. The day 28 overall response rates were 94.6% in skin SR aGVHD, 81.6% in gut SR aGVHD, and 66.7% in liver SR aGVHD. Infectious complications included bacterial infection (11%), presumed or documented fungal infections (7%), cytomegalovirus viremia (53%), Epstein-Barr virus viremia (11%), human herpesvirus-6 viremia (7%), and herpes simplex virus viremia (1%). The 3-year overall survival, disease-free survival, nonrelapse mortality, and relapse rates between responders and nonresponders were 81.3% versus 46.7% (P < .001), 79.0% versus 46.7% (P = .001), 6.1% versus 33.3% (P < .001), and 14.9% versus 20.0% (P = .46), respectively. We conclude that basiliximab is an effective second-line agent for pediatric patients with SR aGVHD after haplo-HSCT, particularly for skin SR aGVHD.

10.
Psychiatr Serv ; 71(1): 75-78, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590622

RESUMO

OBJECTIVE: This study examined whether communication between inpatient and outpatient mental health providers during patients' inpatient stays was associated with whether patients attended postdischarge appointments. METHODS: Psychiatric inpatient medical records of 189 Medicaid recipients at two hospitals were reviewed to document whether inpatient staff had communicated with current or prior outpatient providers. Medicaid claims provided demographic, clinical, and outpatient attendance data. Associations between provider communications and follow-up care for patients who had or had not received outpatient mental health care within the 30 days prior to admission were evaluated. RESULTS: Inpatient staff communicated with outpatient providers for 118 (62%) patients. For patients who had not received outpatient care within 30 days of admission, compared with those who had, communication was associated with increased odds of attending timely outpatient appointments (odds ratio=2.73, 95% confidence interval=1.09-6.84). CONCLUSIONS: Communication with outpatient providers may be especially important for patients who were not engaged in outpatient care prior to admission.

11.
Cytometry B Clin Cytom ; 98(1): 75-87, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31424628

RESUMO

BACKGROUND: This study aimed to determine the impact of the pre- and post-minimal residual disease (MRD) status as well as the peri-transplant MRD kinetics on clinical outcomes in pediatric ALL patients who received haploidentical allografts. METHODS: A retrospective study (n = 166) was performed. MRD was determined using multiparameter flow cytometry. RESULTS: Pediatric ALL patients with pre-MRDneg had a lower cumulative incidences of relapse (CIR) compared to those with pre-MRDpos (19.7% vs. 41.2%, P = 0.009). Compared to post-MRDneg group, patients with post-MRDpos experienced higher CIR (81.0% vs. 15.9%, P < 0.001), inferior LFS (14.3% vs. 66.9%, P < 0.001) and OS (19.1% vs. 66.9%, P < 0.001). In regard to peri-MRD kinetics, compared with the MRD-decreasing group and MRDneg/MRDneg group, MRD-increasing group had higher CIR, lower probabilities of LFS and OS (P < 0.001). Compared to pre-MRDneg/post-MRDneg group, a higher CIR was found in the pre-MRDpos/post-MRDpos group (66.7% vs. 12.5%, P < 0.001), pre-MRDpos/post-MRDneg group (32.0% vs. 12.5%, P = 0.016), and pre-MRDneg/post-MRDpos group (91.7% vs. 12.5%, P < 0.001). A lower incidence of LFS and OS were found in pre-MRDpos/post-MRDpos group and pre-MRDneg/post-MRDpos group than in pre-MRDneg/post-MRDneg group (P < 0.05). Multivariate analyses confirmed the association of pre-MRD status, post-MRD status, and peri-MRD kinetics with outcomes (P < 0.05). CONCLUSIONS: The results indicate that, in the pediatric ALL subgroup, not only pre-MRD status or post-MRD status but also peri-SCT MRD dynamics, were associated with an increased CIR after haploidentical allografts. Patients are put into different risk group based on MRD kinetics versus single time MRD status. © 2019 International Clinical Cytometry Society.

12.
J Affect Disord ; 263: 80-88, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31818800

RESUMO

BACKGROUND: Bipolar disorder (BD) patients show morphological abnormalities in gray matter (GM) and white matter (WM), which can be revealed by structure MRI (sMRI) and diffusion tensor imaging (DTI) respectively. However, previous studies on BD mainly relied on separated analysis of single neuroimaging modality, and it remains unclear how GM and WM covary to the abnormal brain structures of BD patients. METHODS: We recorded multimodal sMRI-DTI data of 35 BD patients and 30 healthy controls (HC) and used multimodal canonical component analysis and joint independent component analysis (mCCA-jICA) to identify altered covariant structures in GM and WM of BD. Group-discriminative and joint group-discriminative independent components (ICs) were identified between BD and HC. Correlation analysis was performed between the mixing coefficients and behavioral index. RESULTS: For BD patients, experiments results revealed that the GM atrophy in inferior frontal gyrus, right anterior cingulate gyrus and left superior frontal gyrus are associated with the WM integrity reduction in corticospinal tract and superior longitudinal fasciculus. Further, compared with HC, different correlation between mixing coefficients of ICs and age was observed for BD patients. LIMITATIONS: The number of participants needs to be increased to more rigorously validate the results of this study, ideally from multiple sites. Functional imaging data could be utilized to explore structural-functional covariant pattern in BD. Possible confounding effect of medication. CONCLUSIONS: We performed fusion analysis of sMRI and DTI and revealed covariant (GM-WM) structural patterns of BD patients. This study could be useful for developing more reliable neural biomarkers of BD.

13.
J Environ Sci (China) ; 87: 310-318, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31791504

RESUMO

Changes in water quality from source water to finished water and tap water at two conventional drinking water treatment plants (DWTPs) were monitored. Beside the routine water quality testing, Caenorhabditis elegans-based toxicity assays and the fluorescence excitation-emission matrices technique were also applied. Both DWTPs supplied drinking water that met government standards. Under current test conditions, both the investigated finished water and tap water samples exhibited stronger lethal, genotoxic and reprotoxic potential than the relative source water sample, and the tap water sample was more lethal but tended to be less genotoxic than the corresponding finished water sample. Meanwhile, the nearly complete removal of tryptophan-like substances and newly generated tyrosine-like substances were observed after the treatment of drinking water, and humic-like substances were identified in the tap water. Based on these findings, toxic pollutants, including genotoxic/reproductive toxicants, are produced in the drinking water treatment and/or distribution processes. Moreover, further studies are needed to clarify the potentially important roles of tyrosine-like and humic-like substances in mediating drinking water toxicity and to identify the potential sources of these contaminants. Additionally, tryptophan-like fluorescence may be adopted as a useful parameter to monitor the treatment performance of DWTPs. Our observations provided insights into the importance of utilizing biotoxicity assays and fluorescence spectroscopy as tools to complement the routine evaluation of drinking water.


Assuntos
Água Potável , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Purificação da Água , Qualidade da Água/normas
14.
Int J Geriatr Psychiatry ; 35(1): 37-44, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31608502

RESUMO

INTRODUCTION: Frailty is a state of vulnerability to stressors resulting in higher morbidity, mortality, and utilization in older adults. Depression and frailty often coexist, suggesting a bidirectional relationship that may increase the effects of each individual condition on clinical outcomes and health-care utilization in older adults. OBJECTIVE: To determine the effects of concurrent frailty and depression on all-cause hospitalizations. METHODS/DESIGN: Prospective cohort study, conducted at a Veterans Affairs (VA) Medical Center. The participants were male, community-dwelling veterans 65 years and older. From 4 January through 30 December 2016, a 46-item frailty index was generated from data obtained from the VA electronic health record. Trained staff conducted in-depth reviews of electronic health records ascertaining depression status. Patients were followed through 31 December 2017 for all-cause hospitalizations following the initial assessment of frailty. After adjusting for covariates, the association of frailty and depression with all-cause hospitalizations was determined with the Andersen-Gill model, accounting for repeated hospitalizations. RESULTS: Five hundred fifty-three male patients were part of the study, mean age 76.3 (SD = 8.2) years. One hundred eighty-one patients (32.7%) had depression diagnoses. During a median follow-up period of 530 days (interquartile range [IQR] = 245), 123 patients (22.2%) had 240 hospitalizations. Frailty status was not associated with future hospitalizations (adjusted hazard ratio [HR] = 1.61; 95% CI, 95-2.74; P > .05). Depression was associated with higher all-cause hospitalizations (adjusted HR = 1.57; 95% CI, 1.09-2.26); P = .0157). CONCLUSIONS: Depression but not frailty was significantly associated with higher rates of all-cause hospitalization. Implementing interventions that target older adults with both frailty and depression may reduce the burden of both conditions and reduce hospitalizations.

15.
Chem Commun (Camb) ; 56(6): 960-963, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31859290

RESUMO

Direct access to benzo-fused aza-macrolides was successfully achieved through iridium-catalysed intermolecular decarboxylative coupling of vinylethylene carbonates with isatoic anhydrides under relatively mild reaction conditions. Notably, this reaction proceeded through sequential allyl-amination/macrolactonization upon extrusion of CO2. Moreover, favourable fluorescence properties could be observed in the title macrocyclic products.

16.
Ophthalmic Res ; : 1-11, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31614358

RESUMO

BACKGROUND: The purpose of this study is to determine the mutation frequencies of key driver genes in uveal melanoma (UM) in Chinese patients and to detect associations between metastasis and the mutation of these genes. METHOD: A total of 85 patients with UM were enrolled in this study, including 18 patients with metastasis and 67 without metastasis. Sanger sequencing covering the mutational hotspot regions of the G protein subunit alpha Q (GNAQ), GNA11, splicing factor 3B subunit 1 (SF3B1), X-linked eukaryotic translation initiation factor 1A (EIF1AX), phospholipase C beta 4 (PLCB4) and cysteinyl leukotriene receptor 2 (CYSLTR2) genes was used to analyse the mutations in Chinese patients. RESULTS: The frequencies of GNAQ and GNA11 mutations in UM were 45% (38/85) and 35% (30/85) respectively. The frequencies of SF3B1 and EIF1AX mutations were 37% (31/85) and 9% (8/85) respectively. Only 2 mutations were detected in exon 4 of GNAQ, and no mutations were detected in exon 4 of GNA11. A novel mutation, c.627G>T (Q209H) in GNA11 was found. The detected mutations affecting SF3B1 were c.1873C>T (R625C), c.1874G>A (R625H) and c.1874G>T (R625L). The association between the mutations in SF3B1 and low risk of metastasis was statistically significant (OR 0.17, 95% CI 0.035-0.819). The mutations affecting EIF1AX were -23G>A (5'-UTR), c.5C>G (P2R), c.23G>A (G8Q), c.25G>C (G9A) and c.38_39GC>CT (R13P). No mutations were found in the PLCB4 and CYSLTR2 genes. Unfortunately, information on BRCA1-associated protein 1 could not be obtained. CONCLUSIONS: These data indicate that mutations in the PLCB4 and CYSLTR2 genes are rare in Chinese UM patients. The mutations in GNAQ, GNA11 and EIF1AX were not associated with metastasis, whereas SF3B1 mutations were correlated with low risk of metastasis and demonstrated a protective effect in UM patients in China.

17.
Nanoscale ; 11(43): 20942-20948, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31660567

RESUMO

All-inorganic lead halide perovskite quantum dots (PQDs) of CsPbBr3 were synthesized at room temperature via a facile solution-based procedure. The cubic phase structure of the synthesized PQDs was judiciously identified through examining high-resolution transmission electron microscopy (TEM) images, selected area electronic diffraction (SAED) patterns and scanning TEM images of the PQDs. Variable-temperature photoluminescence (PL) spectra of the CsPbBr3 PQDs randomly embedded into a frozen solid of methylbenzene were measured in the temperature range of 5-180 K. It is found that both the linewidth and peak position of the measured PL spectra are abnormally almost temperature independent in the temperature range of interest. Some competing mechanisms, such as a competition between the bandgap blue shift induced by thermal lattice expansion and red shift induced by thermal escaping of localized excitons, and a competition between lineshape broadening by phonon scattering and narrowing by thermal escaping of localized excitons, are proposed to interpret the phenomena. Good agreement between the theoretical fitting and the experimental data leads to a state-of-the-art understanding of the temperature-dependent luminescence of the CsPbBr3 PQDs in a solid matrix.

18.
Wei Sheng Yan Jiu ; 48(4): 583-593, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601339

RESUMO

OBJECTIVE: To understand the differences in the types and levels of antibiotic resistance genes contamination in the dust of air conditioning filters in hospital inpatient wards. METHODS: Wet cotton swabs were used to collect dust samples from air conditioning filters in 19 wards of 7 departments of a third-grade general hospital in Wuhan. The 24 antibiotic resistance genes related to 6 major antibiotics were qualitatively detected by PCR, and 6 typical resistance genes were detected by real-time PCR. RESULTS: Sulfonamides(sulI, sulII), ß-lactams(mecA, blaOXA-51, blaTEM, blaCTX-M, blaSHV, blaKPC, blaNDM-1, blaIMP, blaVIM), aminoglycosides(aac(6᾿-aph(2᾿, aacC2), macrolides(ermA, ermC, ereA), quinolones(qnrA, qnrB, qnrS), a total of five categories of 19 antibiotic resistance genes were detected in the dust of the filter. These include four carbapenem resistance genes(blaNDM-1, blaIMP, blaVIM, blaKPC). The average of absolute content(copies/g) of the six typical resistance genes from high to low was: sulI(1. 06×10~9)>sulII(1. 78×10~8)>blaNDM-1(3. 97×10~7)>aac(6᾿-aph(2᾿(3. 20×10~7)>blaTEM(1. 03×10~7)>aacC2(1. 13×10~6). Among the seven tested departments, traumatic surgery detected up to 18 resistant gene species and 6 typical genes with the highest absolute content. The absolute content of six typical genes in ICU and surgical wards was higher than medical wards. CONCLUSION: A variety of antibiotic resistance genes are detected in the dust of some hospital ward air conditioning filters, suggesting that there may be current or past pollution of resistant bacteria in the relevant environment.


Assuntos
Ar Condicionado , Microbiologia do Ar , Resistência Microbiana a Medicamentos/genética , Poeira/análise , Antibacterianos , Carbapenêmicos , China , Testes de Sensibilidade Microbiana , beta-Lactamases
19.
ACS Appl Mater Interfaces ; 11(42): 38616-38624, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31556992

RESUMO

We propose a flexible and wearable thermoelectric nanogenerator (FTEG) made from Bi2Te3, which allows high voltage and output power density. The proposed FTEG works as a thermopile with the end-to-end connection of 126 thermoelectric legs, and which is fabricated through magnetron sputtering Cu conductor on polyethylene terephthalate film. Bi, Te, Sb, and Se alloys are used to prepare thermoelectric materials by doping in a fixed proportion and zone melting, and nickel plating on the surface mitigates the deterioration of thermoelectric properties caused by the diffusion of Cu atoms or Cu+ ions. The thermoelectric figure of merit is stable and maintained above 0.7, up to 1.02. More flexibility is allowed by employing double sinusoidal serpentine connecting wires, and no significant property changes are observed even after being folded 200 times. When the temperature difference reaches 50 K, the output voltage of the FTEG will be no less than 520 mV, and the power density will reach 11.14 mW·cm-2. By integration of a low-power, low-threshold voltage boost circuit on the back end of the FTEG, the electronic watch with a liquid crystal display screen can be easily powered to work properly. Furthermore, the FTEG is temperature-sensitive and, thus, can be used for temperature measurement with a resolution of 0.5 K. This work may have important prospects in flexible wearable physical sensors and individualized medical care.

20.
Nat Prod Res ; : 1-5, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31502480

RESUMO

The serotonin (5-hydroxytryptamine) type 3 receptor is an important target in the control of digestive dysfunction such as anorexia and bulimia, and 5-HT3 receptor antagonists are effective against eating disorder and the early-phase chemotherapy and radiotherapy evoked vomiting. Our previous research of Valeriana jatamansi revealed the presence of iridoids, which showed potent antitumor activities. Here, we explored the effects of 10π aromatic iridoid desacylbaldrinal isolated from V. jatamansi on the 5-HT3 receptor current. We performed whole cell recordings of 5-HT3A receptor currents in the presence of the compound. The result indicated that desacylbaldrinal inhibited the 5-HT-mediated 5-HT3A receptor current.

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