Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 751
Filtrar
1.
Org Biomol Chem ; 19(17): 3820-3824, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33949582

RESUMO

By employing a chiral phosphoric acid as a catalyst, an enantioselective aza-Friedel-Crafts reaction of 5-aminoisoxazoles with isatin-derived N-Boc ketimines was realized. The reaction provided a wide variety of novel 3-isoxazole 3-amino-oxindoles with good yields (up to 99%) and moderate to good enantioselectivities (up to 99%). The absolute configuration of one product was assigned by X-ray crystal structural analysis and a plausible reaction mechanism was proposed. In addition, a scale-up reaction was performed successfully. Finally, one product was subjected to Suzuki-Miyaura coupling with phenylboronic acid to afford the product in a moderate yield without erosion of the enantioselectivity.

2.
JBI Evid Implement ; 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33843767

RESUMO

OBJECTIVES: The current evidence implementation project aims to promote evidence-based practice in the care of patients with stroke, specifically around the prevention of deep venous thrombosis (DVT), in the neurology department of a tertiary hospital in Guangzhou, China. INTRODUCTION: The prevalence of DVT within 14 days after stroke is 10-75%. Approximately 20% of patients with DVT develop pulmonary embolism, the third most common cause of death in patients with stroke and the most common cause of autopsy-verified death between the second and fourth week after stroke. Several risk factors are associated with the development of DVT, many of which can be alleviated by evidence-based strategies that can prevent or reduce the risk of DVT. METHODS: The current evidence implementation project utilized the Joanna Briggs Institute Practical Application of Clinical Evidence System program and involved 30 patients in each audit criterion. Interventions included staff education, involvement of rehabilitation staff, and building a patient education bundle. A postimplementation reaudit was undertaken including the same number of patient samples. RESULTS: The baseline audit results showed that the compliances for two audit criteria (patient mobilization and patient education) were under 20%, whereas those for the other criteria were at least 60%. After implementing the strategies, there were significant improvements especially in the two weak-compliance criteria. In addition, the overall compliance for most criteria increased. CONCLUSION: The project standardized the DVT prevention process in the Neurology Department of Nanfang Hospital. The overall compliance with DVT prevention for patients with stroke in the department improved.

3.
Curr Med Sci ; 41(2): 368-374, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33877555

RESUMO

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. Several studies have indicated that rectal cancer is significantly different from colon cancer in terms of treatment, prognosis, and metastasis. Recently, the differential mRNA expression of colon cancer and rectal cancer has received a great deal of attention. The current study aimed to identify significant differences between colon cancer and rectal cancer based on RNA sequencing (RNA-seq) data via support vector machines (SVM). Here, 393 CRC samples from the The Cancer Genome Atlas (TCGA) database were investigated, including 298 patients with colon cancer and 95 with rectal cancer. Following the random forest (RF) analysis of the mRNA expression data, 96 genes such as HOXB13, PRAC, and BCLAF1 were identified and utilized to build the SVM classification model with the Leave-One-Out Cross-validation (LOOCV) algorithm. In the training (n=196) and the validation cohorts (n=197), the accuracy (82.1 % and 82.2 %, respectively) and the AUC (0.87 and 0.91, respectively) indicated that the established optimal SVM classification model distinguished colon cancer from rectal cancer reasonably. However, additional experiments are required to validate the predicted gene expression levels and functions.

4.
Adv Mater ; : e2008761, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33876467

RESUMO

Exploring 2D ultrawide bandgap semiconductors (UWBSs) will be conductive to the development of next-generation nanodevices, such as deep-ultraviolet photodetectors, single-photon emitters, and high-power flexible electronic devices. However, a gap still remains between the theoretical prediction of novel 2D UWBSs and the experimental realization of the corresponding materials. The cross-substitution process is an effective way to construct novel semiconductors with the favorable parent characteristics (e.g., structure) and the better physicochemical properties (e.g., bandgap). Herein, a simple case is offered for rational design and syntheses of 2D UWBS GaPS4 by employing state-of-the-art GeS2 as a similar structural model. Benefiting from the cosubstitution of Ge with lighter Ga and P, the GaPS4 crystals exhibit sharply enlarged optical bandgaps (few-layer: 3.94 eV and monolayer: 4.50 eV) and superior detection performances with high responsivity (4.89 A W-1 ), high detectivity (1.98 × 1012 Jones), and high quantum efficiency (2.39 × 103 %) in the solar-blind ultraviolet region. Moreover, the GaPS4 -based photodetector exhibits polarization-sensitive photoresponse with a linear dichroic ratio of 1.85 at 254 nm, benefitting from its in-plane structural anisotropy. These results provide a pathway for the discovery and fabrication of 2D UWBS anisotropic materials, which become promising candidates for future solar-blind ultraviolet and polarization-sensitive sensors.

5.
Mar Pollut Bull ; 167: 112261, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33799145

RESUMO

Seagrass beds are highly productive coastal ecosystems that are widely distributed along temperate and tropical coastlines globally. Although seagrass distribution and diversity have been widely reported on a global scale, there have been few reports on seagrass distribution and diversity in northern China, especially for coastal waters of the Liaodong Peninsula in the North Yellow Sea. In the present study, we investigated the distribution and diversity of seagrass in coastal waters of the Liaodong Peninsula in the North Yellow Sea, northern China. Field surveys of seagrass wrack were conducted along shorelines, to identify whether seagrass beds occurred in nearby waters, and sonar methods were then used to collect data relating to seagrass bed extent. Also, we analyzed the major threats facing seagrass beds. The results of the study revealed that four species (Zostera marina L., Z. japonica Aschers. & Graebn., Z. caespitosa M., and Phyllospadix iwatensis M.) were found in study area, covering a total area of 1253.47 ha. Seagrass bed area significantly decreased with increasing water depth, and most seagrass was recorded at depths of 2-5 m. Due to the steep slope of the seabed, seagrass beds exhibited a zonal distribution in most of the study areas. In addition, the amount of seagrass wrack along shorelines could be used to infer the size and distance of seagrass beds. Human activities, such as clam harvesting, land reclamation, coastal aquaculture pose a threat to the seagrass beds. This study provides new information to fill knowledge gaps regarding seagrass distribution in northern China and it provides a baseline for further monitoring of these seagrass beds.

6.
Cells ; 10(4)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919979

RESUMO

Macrophages are widely distributed in tissues and function in homeostasis. During cancer development, tumor-associated macrophages (TAMs) dominatingly support disease progression and resistance to therapy by promoting tumor proliferation, angiogenesis, metastasis, and immunosuppression, thereby making TAMs a target for tumor immunotherapy. Here, we started with evidence that TAMs are highly plastic and heterogeneous in phenotype and function in response to microenvironmental cues. We pointed out that efforts to tear off the heterogeneous "camouflage" in TAMs conduce to target de facto protumoral TAMs efficiently. In particular, several fate-mapping models suggest that most tissue-resident macrophages (TRMs) are generated from embryonic progenitors, and new paradigms uncover the ontogeny of TAMs. First, TAMs from embryonic modeling of TRMs and circulating monocytes have distinct transcriptional profiling and function, suggesting that the ontogeny of TAMs is responsible for the functional heterogeneity of TAMs, in addition to microenvironmental cues. Second, metabolic remodeling helps determine the mechanism of phenotypic and functional characteristics in TAMs, including metabolic bias from macrophages' ontogeny in macrophages' functional plasticity under physiological and pathological conditions. Both models aim at dissecting the ontogeny-related metabolic regulation in the phenotypic and functional heterogeneity in TAMs. We argue that gleaning from the single-cell transcriptomics on subclonal TAMs' origins may help understand the classification of TAMs' population in subclonal evolution and their distinct roles in tumor development. We envision that TAM-subclone-specific metabolic reprogramming may round-up with future cancer therapies.

7.
Diabetes Care ; 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33832957

RESUMO

OBJECTIVE: This study aimed to evaluate the efficacy and safety of mulberry twig alkaloids (Sangzhi alkaloids [SZ-A]) in the treatment of type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS: This was a multicenter, randomized, double-blind, double-dummy, and parallel controlled noninferiority clinical trial that was conducted for 24 weeks. A total of 600 patients were randomly allocated to the SZ-A group (n = 360) or acarbose group (n = 240). The primary efficacy end point was the change of glycosylated hemoglobin (HbA1c) compared with baseline. In addition, adverse events (AEs), severe AEs (SAEs), treatment-related AEs (TAEs), and gastrointestinal disorders (GDs) were monitored. RESULTS: After treatment for 24 weeks, the change in HbA1c was -0.93% (95% CI -1.03 to -0.83) (-10.2 mmol/mol [-11.3 to -9.1]) and -0.87% (-0.99 to -0.76) (-9.5 mmol/mol [-10.8 to -8.3]) in the SZ-A and acarbose groups, respectively, and the least squares mean difference was -0.05% (95% CI -0.18 to 0.07) (-0.5 mmol/mol [-2.0 to 0.8]) between the two groups, with no significant difference on the basis of covariance analysis (P > 0.05). The incidence of TAEs and GDs was significantly lower in the SZ-A group than the acarbose group (P < 0.01), but no differences for AEs or SAEs between the two groups were observed (P > 0.05). CONCLUSIONS: SZ-A exhibited equivalent hypoglycemic effects to acarbose in patients with T2D. Nevertheless, the incidence of TAEs and GDs was lower following SZ-A treatment than acarbose treatment, suggesting good safety.

8.
J Diabetes Res ; 2021: 5537110, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33928166

RESUMO

This study was aimed at exploring the predictive value of first-trimester glycosylated hemoglobin (HbA1c) levels in the diagnosis of gestational diabetes mellitus (GDM). A total of 744 pregnant women registered at the Peking University International Hospital between March 2017 and March 2019 were included in this study. Data on personal characteristics and biochemical indicators of the pregnant women were collected during the first trimester. The International Association of Diabetes and Pregnancy Study Groups has adopted specific diagnostic criteria as the gold standard for the diagnosis of GDM. Receiver operating characteristic (ROC) curve statistics were used to assess the predictive value of first-trimester HbA1c levels in the diagnosis of GDM. HbA1c levels in the first trimester were significantly higher in the GDM group than in the non-GDM group (5.23% ± 0.29% vs. 5.06 ± 0.28%, P < 0.05). The first-trimester HbA1c level was an independent risk factor for gestational diabetes. The area under the ROC curve (AUC) of HbA1c for GDM was 0.655 (95% confidence interval 0.620-0.689, P < 0.001). The positive likelihood ratio was the highest at HbA1c = 5.9%, sensitivity was 2.78, and specificity was 99.83%. There was no statistical difference in AUC between fasting blood glucose and HbA1c (P = 0.407). First-trimester HbA1c levels can be used to predict GDM. The risk of GDM was significantly increased in pregnant women with first-trimester HbA1c levels > 5.9%. There was no statistical difference between first-trimester HbA1c and fasting blood glucose levels in predicting GDM.

9.
Chem Commun (Camb) ; 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33928973

RESUMO

A NaI-promoted sequential double carbon-sulfur bond formation was developed to afford sulfur-bridged imidazopyridines, using Deoxofluor as the sulfur source and requiring only 15 min at room temperature. Using this process, imidazo[1,5-a]pyridines could also be transformed to 1,2,4-thiadiazoles in the presence of ammonium salt with the formation of both carbon-sulfur and nitrogen-sulfur bonds. This mechanistically unique method is distinguished by its wide substrate scope, lack of requirement for transition metals and mild conditions.

10.
Sci Total Environ ; 768: 144717, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33736305

RESUMO

Coastal hypoxia/anoxia is a major emerging threat to global coastal ecosystems. Macroalgae blooms of tens of kilometers are often observed in open waters. These blooms not only cause a lack of oxygen, but also benthic light limitation. We explored the physiological responses of Zostera marina L. to anoxia under darkness. After exposing Z. marina to anoxia under darkness for 72 h, we measured the elongation of leaves and the decrease in maximal quantum yield of photosystem II (Fv/Fm), and investigated the transcriptomic and metabolomic responses to anoxic stress based on RNA-sequencing and liquid chromatography-mass spectrometry (LC-MS) technology. The results showed that anoxic stress significantly reduced the leaf Fv/Fm, and had a significant negative effect on the photosynthesis and growth of Z. marina. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of up-regulated differentially expressed genes (DEGs) showed that glycolysis was the most significant enrichment pathway (p < 0.001), and most of the important products in glycolysis were significantly up-regulated. This indicated that the glycolysis process of anaerobic respiration is promoted under anoxia. The metabolite results also showed that glyceraldehyde 3-phosphate in the glycolysis pathway was significantly up-regulated. Moreover, three genes encoding sucrose synthase (gene-ZOSMA_310G00150, gene-ZOSMA_81G00980, and gene-ZOSMA_8G00730) and one gene encoding alpha-amylase (gene-ZOSMA_95G00270) were significantly up-regulated, providing the sugar basis for the subsequent increase in glycolysis. Furthermore, gene-encoding oxoglutarate dehydrogenase, the rate-limiting step of the tricarboxylic acid (TCA) cycle, was significantly down-regulated, indicating that this cycle was inhibited under anoxia. Metabolomic results showed that L-tryptophan, L-phenylalanine, and DL-leucine were significantly up-regulated. Only significantly decreased glutamate and non-significantly decreased glutamine, substances consumed in alanine and γ-aminobutyric acid (GABA) shunt mechanisms, were detected in the leaves, while GABA and alanine were not detected. The results of this study show that anoxic stress induces a programmed transcriptomic and metabolomic response in seagrass, most likely reflecting a complex strategy of acclimation and adaptation in seagrass to resist anoxic stress.


Assuntos
Zosteraceae , Escuridão , Ecossistema , Humanos , Hipóxia , Metabolômica , Transcriptoma , Zosteraceae/genética
11.
Food Chem ; 352: 129379, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33676121

RESUMO

An HILIC-ESI-MS/MS method was established to analyze ganglioside (GLS) in sea cucumbers. In total, 17 GLS subclasses were detected in six sea cucumber species. The basic sea cucumber GLSs (SC-GLSs) were elucidated as NeuGc2-6Glc1-1Cer (SC-GM4). The polymerization degree of the sialic acid (Sia) of SC-GLSs can be up to 4, and the linkage among Sias was mostly determined to be 2-8 or 2-11. Neu5Gc, sulfated and fucosylated NeuGc prevalently existed in SC-GLSs. Moreover, a new SC-GLSs structure with phosphoinositidyled Sia was first observed in Bohadschia marmorata. For the first time, we demonstrated that the content of SC-GD4, which is the dominant GLS in sea cucumbers, was 27-67%. Minor GLSs characterized as SC-GT2(Neu5GcMe) and SC-GQ2(Neu5GcMe) were also discovered. Additionally, SC-GD4 and SC-GD4(1S) could significantly promote the differentiation of PC12 cells with structure-selectivity (p < 0.05). Our results provide insights into SC-GLSs to elucidate their Sia substituent and core saccharide chain linkage.


Assuntos
Gangliosídeos/análise , Pepinos-do-Mar/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Animais , Gangliosídeos/química , Glucosinolatos/química , Ácido N-Acetilneuramínico/química
12.
Antonie Van Leeuwenhoek ; 114(5): 497-506, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33661468

RESUMO

A Gram-stain-negative, light yellow pigmented, non-motile and aerobic bacterial strain, designated HHU E2-1 T, was isolated from a surface seawater sample. The 16S rRNA gene sequence analysis indicated that HHU E2-1 T shared the highest sequence similarity to the type strain Qipengyuania gaetbuli DSM 16225 T (96.90%), which belongs to the family Erythrobacteraceae. Combined phylogeny of 288 single-copy orthologous gene clusters, analysis of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH), average amino acid identity (AAI) and evolutionary distances suggested that HHU E2-1 T can be considered as a member of the genus Altererythrobacter based on the recently proposed standard for defining genera of Erythrobacteraceae. Strain HHU E2-1 T grew at 15-35 °C and pH 5.0-8.0, with optimum growth at 28 °C and pH 7.0. Tolerance to NaCl was up to 4% (w/v) with optimum growth in 2-3% NaCl. The major fatty acids (> 10%) were C18:1ω7c11-methyl, summed feature 3 (C16:1ω7c and/or C16:1ω6c), and summed feature 8 (C18:1ω7c and/or C18:1ω6c). The predominant isoprenoid quinone was ubiquinone-10. The genomic G + C content was 57.40%. On the basis of the phenotypic, phylogenetic and chemotaxonomic characterizations, HHU E2-1 T represents a novel species of the genus Altererythrobacter, for which the name Altererythrobacter flava sp. nov. is proposed. The type strain is HHU E2-1 T (= CGMCC 1.17394 T = KCTC 72835 T = MCCC 1K04226T).

13.
Nanomaterials (Basel) ; 11(2)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670159

RESUMO

The photovoltaic effect in the anodic formation of silicon dioxide (SiO2) on porous silicon (PS) surfaces was investigated toward developing a potential passivation technique to achieve high efficiency nanostructured Si solar cells. The PS layers were prepared by electrochemical anodization in hydrofluoric acid (HF) containing electrolyte. An anodic SiO2 layer was formed on the PS surface via a bottom-up anodization mechanism in HCl/H2O solution at room temperature. The thickness of the oxide layer for surface passivation was precisely controlled by adjusting the anodizing current density and the passivation time, for optimal oxidation on the PS layer while maintaining its original nanostructure. HRTEM characterization of the microstructure of the PS layer confirms an atomic lattice matching at the PS/Si interface. The dependence of photovoltaic performance, series resistance, and shunt resistance on passivation time was examined. Due to sufficient passivation on the PS surface, a sample with anodization duration of 30 s achieved the best conversion efficiency of 10.7%. The external quantum efficiency (EQE) and internal quantum efficiency (IQE) indicate a significant decrease in reflectivity due to the PS anti-reflection property and indicate superior performance due to SiO2 surface passivation. In conclusion, the surface of PS solar cells could be successfully passivated by electrochemical anodization.

14.
J Clin Monit Comput ; 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33709233

RESUMO

To evaluate the effect of different inflation volume on the measurement accuracy of the modified cuff pressure measurement method in different shapes of cuffs, so as to provide reference for the correct monitoring of cuff pressure in clinic. In vitro study: The traditional cuff pressure measurement method (the cuff pressure gauge before measurement shows 0 cm H2O) and the modified cuff pressure measurement method (the cuff pressure before measurement shows 25 cm H2O, 28 cm H2O, 30 cm H2O or 32 cm H2O) were used to measure cylindrical and tapered cuffs, and the effect of different inflation volume on cuff pressure was analyzed statistically. Clinical study: patients with the artificial airway established by orotracheal intubation or tracheotomy in Neuro-ICU were prospectively selected as subjects, and the measurement procedure was the same as in vitro study. In vitro study showed that the pressure loss values of cylindrical cuff and tapered cuff using the traditional cuff pressure measurement method were (3.75 ± 0.31) cm H2O and (4.92 ± 0.44) cm H2O, respectively, and clinical study showed that the pressure loss values were (5.07 ± 0.83) cm H2O and (5.17 ± 0.93) cm H2O, respectively. The actual measured values measured by the traditional cuff pressure measurement method of the two cuff shapes were compared with the corrected target value of 28 cm H2O, and the differences were statistically significant (P < 0.000). Both in vitro and clinical study had shown that all differences between the actual measured value and the corrected target value using the modified cuff pressure measurement method (measured with 25 cm H2O, 30 cm H2O, 32 cm H2O) were statistically significant (P < 0.000), and the range of overall differences was (0-1.23 ± 0.25) cm H2O. In vitro study had shown that the pressure variation coefficient (CV) of the tapered cuff was greater than that of the cylindrical cuff, and the difference was statistically significant (3.08 ± 0.25 VS 2.41 ± 0.21, P < 0.000). The traditional cuff pressure measurement method can directly lead to the cuff pressure drop, which is easy to cause the leakage of secretions on the cuffs and the misjudgment of the cuff pressure by medical personnel. However, the modified cuff pressure measurement method can effectively reduce cuff pressure loss, and taking the actual cuff pressure value as the inflation volume is the highest measurement accuracy.The tapered cuff is more susceptible to air volume, so it is necessary to pay attention to its measurement and correction in clinical practice.

15.
J Dairy Sci ; 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33714585

RESUMO

Functional dyspepsia (FD) is a common disease of the digestive system and probiotics have been reported to be effective in the treatment of functional gastrointestinal diseases. The aim of this study was to determine the effect of the beverage containing Lactobacillus paracasei LC-37 (LC-37) and its ability to relieve symptoms of FD by a randomized clinical trial. Due to the mechanistic complexity underlying FD, intestinal microbiota and stool metabolomes were also evaluated. The results showed that FD was relieved in subjects after treatment with the beverage containing LC-37 for 14 and 28 d. The clinical symptom scores were significantly decreased after these times (abdominal pain and belching were significantly decreased after 14 d and almost absent after 28 d of treatment). Probiotics, such as those containing the Lactobacillus, Lactococcus, and Weissella, significantly increased, and the abundance of harmful bacteria such as Lachnocliostridium significantly decreased. Furthermore, relevant beneficial intestinal metabolites such as pelargonic acid, benzoic acid, and short-chain fatty acids increased, and harmful intestinal metabolites such as hippuric acid decreased. Taken together, these findings suggested that the beverages containing LC-37 can increase the abundance of probiotics and decrease pathogenic bacteria, and thereby improve beneficial intestinal metabolites. Therefore, the beverages containing LC-37 may provide a natural alternative to combat FD.

16.
Front Cell Infect Microbiol ; 11: 640309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777850

RESUMO

To characterize the salivary microbiota in patients at different progressive histological stages of gastric carcinogenesis and identify microbial markers for detecting gastric cancer, two hundred and ninety-three patients were grouped into superficial gastritis (SG; n = 101), atrophic gastritis (AG; n = 93), and gastric cancer (GC; n = 99) according to their histology. 16S rRNA gene sequencing was used to access the salivary microbiota profile. A random forest model was constructed to classify gastric histological types based on the salivary microbiota compositions. A distinct salivary microbiota was observed in patients with GC when comparing with SG and AG, which was featured by an enrichment of putative proinflammatory taxa including Corynebacterium and Streptococcus. Among the significantly decreased oral bacteria in GC patients including Haemophilus, Neisseria, Parvimonas, Peptostreptococcus, Porphyromonas, and Prevotella, Haemophilus, and Neisseria are known to reduce nitrite, which may consequently result in an accumulation of carcinogenic N-nitroso compounds. We found that GC can be distinguished accurately from patients with AG and SG (AUC = 0.91) by the random forest model based on the salivary microbiota profiles, and taxa belonging to unclassified Streptophyta and Streptococcus have potential as diagnostic biomarkers for GC. Remarkable changes in the salivary microbiota functions were also detected across three histological types, and the upregulation in the isoleucine and valine is in line with a higher level of these amino acids in the gastric tumor tissues that reported by other independent studies. Conclusively, bacteria in the oral cavity may contribute gastric cancer and become new diagnostic biomarkers for GC, but further evaluation against independent clinical cohorts is required. The potential mechanisms of salivary microbiota in participating the pathogenesis of GC may include an accumulation of proinflammatory bacteria and a decline in those reducing carcinogenic N-nitroso compounds.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33538681

RESUMO

BACKGROUND: Bibliometric analysis can analyze development trends and predict research hotspots. We used these analyses to better understand pregnancy-related implications of thyroid diseases. METHODS: Publications on thyroid diseases during pregnancy from 1926 to hitherto were retrieved based on the Web of Science database. The publications and references, the institutions and countries, the journals, the keywords and citations, were analyzed by utilizing VOSviewer, CiteSpace and CitNetExplorer. RESULTS: A total of 3310 publications were retrieved and were cited 87913 times. The United States took the dominant position in outputs and collaborations. Harvard University had the most articles 86, which also had the highest h-index 30. Thyroid ranked first with 201 publications and Journal of Clinical Endocrinology Metabolism had the highest h-index 67. Among the 49 burst keywords, "antibody" had the longest burst period from 1991 to 2012, "thyroxine" had the strongest burst strength 16.7026, "hypothyroxinemia" appeared most recently in 2018. The most frequent keyword was "pregnancy" occurred 1324 times. All the top 98 frequent keywords were clustered into 4 clusters. The citation network visualization was grouped into 8 groups. CONCLUSION: The research focus of thyroid diseases in pregnancy ranged from clinical thyroid dysfunction to milder thyroid dysfunction. Guidelines published by the American Thyroid Association enacted a crucial purpose in the treatment and development of thyroid diseases during pregnancy. Some randomized controlled studies of unresolved problems and long-term follow-up of offspring may be the direction of future research. In the meantime, bibliometric methods can help scholars choose journals, track research hotspots, and identify the direction or focus of future research.

18.
J Diabetes Res ; 2021: 6630020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33628835

RESUMO

OBJECTIVE: To analyze the differences of early atherosclerosis indices in type 2 diabetes mellitus (T2DM) patients with different degrees of obstructive sleep apnea-hypopnea syndrome (OSAHS) and explore the correlation between them, so as to provide a new clinical basis for the prevention and treatment of early atherosclerosis in patients with T2DM and OSAHS. Methods. A prospective study was conducted in 312 patients with T2DM and snoring who were hospitalized in the Department of Endocrinology, Peking University International Hospital from January 2017 to January 2020. According to the monitoring results, 312 patients were divided into 4 groups including the control group (208 cases), mild OSAHS group (18 cases), moderate OSAHS group (38 cases), and severe OSAHS group (48 cases). Multivariate logistic regression analysis was used to analyze the early atherosclerosis indices including brachial-ankle pulse wave velocity (PWV) and ankle-brachial index (ABI) in patients with T2DM coexistence with different degrees of OSAHS. Results. (1) As the degree of OSAHS increased, ABI decreased gradually and was lower than that in the control group, but PWV increased and was higher than that in the control group (p < 0.05, respectively). (2) The apnea-hypopnea index (AHI) positively correlated with PWV (r = 0.36, p < 0.05) and negatively correlated with ABI (r = -0.37, p < 0.05). (3) Multivariate logistic regression showed that after adjusting for age, gender, duration, BMI, blood pressure, blood glucose, blood lipid, and other factors, OSAHS was a risk factor of lower extremity arterial disease (LEAD) in patients with T2DM. With the increase of degree of OSAHS, the risk of lower extremity atherosclerosis gradually increased. Conclusion. OSAHS is an independent risk factor of LEAD in patients with T2DM, and with the increase of AHI, the ABI and PWV have changed, which provides a new clinical basis for the prevention and the treatment of early atherosclerosis in patients with T2DM and OSAHS.

19.
J Phys Chem Lett ; : 1973-1978, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33594881

RESUMO

Herein, we employed lead-free Cs3Cu2I5 perovskite films as the functional layers to construct Al/Cs3Cu2I5/ITO memory devices and systematically investigated the impact on the corresponding resistive switching (RS) performance via adding different amounts of hydroiodic acid (HI) in Cs3Cu2I5 precursor solution. The results demonstrated that the crystallinity and morphology of the Cs3Cu2I5 films can be improved and the resistive switching performance can be modulated by adding an appropriate amount of HI. The obtained Cs3Cu2I5 films by adding 5 µL HI exhibit the fewest lattice defects and flattest surface (RMS = 13.3 nm). Besides, the memory device, utilizing the optimized films, has a low electroforming voltage (1.44 V), a large on/off ratio (∼65), and a long retention time (104 s). The RS performance impacted by adding HI, providing a scientific strategy for improving the RS performance of iodine halide perovskite-based memories.

20.
Endocr Connect ; 10(2): 139-145, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33543732

RESUMO

Aims: To estimate the sex differences in the prevalence of overweight and obesity aged 20-89 in Chinese patients with type 2 diabetes (T2D). Methods: 811,264 patients with T2D from six hospital-based, cross-sectional studies, and 46,053 subjects from the general population were included in our analysis. Prevalence of underweight, overweight, obesity were calculated in each sex. Results: In patients with T2D, the standardized prevalence of underweight (BMI <18.5 kg/m2), overweight (24 kg/m2 ≤ BMI < 28 kg/m2), and general obesity (BMI ≥28 kg/m2) were 2.2%, 43.2%, and 11.6%, respectively. Similar trend patterns of the prevalence of underweight and overweight were observed in general and T2D population, in males and females with T2D (all P for trend <0.01). In patients with T2D, patients at a younger age and older age were more likely to be underweight. The prevalence of overweight increased first, then stabilized or decreased with age. However, different trend patterns of the prevalence of obesity in males and females were found. In males, the prevalence of obesity decreased first, and then stabilized after 60 years of age. In females, the prevalence of obesity decreased first, then increased after 50 years of age. In the general population, the prevalence of obesity increased with age in females, while, the trend of prevalence of obesity with age in males was not obvious. Conclusion: Different trends in the prevalence of obesity with age in different sex were found in Chinese patients with T2D.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...