Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 656
Filtrar
1.
BMC Cancer ; 21(1): 330, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789613

RESUMO

BACKGROUND: This study aimed to investigate skin condition, quality of life, and psychological impact of breast cancer patients after radiation therapy. We designed and administered a questionnaire to breast cancer survivors for better understanding the skin sequelae after radiation therapy. METHODS: This study performed an anonymous online survey. Invitation join was posted in Facebook groups for Breast Cancer. Content of the questionnaire included basic information and a three-point scale on the degree of skin dryness, sweating, hotness sensation, itchy sensation, presence of pigment deposition, history of severe skin disorder, psychological impact, and quality of life after radiotherapy. Categorical variables were summarized using counts and percentages, and then Mantel-Haenszel chi-square tests, multiple correspondence analysis, Wald chi-square statistics, and logistic regression analyses were performed; P < 0.05 was considered statistically significant. RESULTS: In total, 421 breast cancer survivors completed the questionnaire. Among them, 331 (78.62%) reported rarely sweating; 340 (80.76%) reported dry skin; 184 (43.71%) reported itchy skin in addition to dry skin; 336 (79.81%) had severe or mild skin color deposition; and 76 (18.05%) had eczema or contact dermatitis. Dry skin problems were caused by absent sweating and skin dryness in the irradiated skin area, post-RT severe skin disorders, and skin color deposition. Compared with patients sweating normally in the radiation field, patients with absent sweating and hotness sensation in the radiation field had a higher risk of depression. CONCLUSIONS: This study showed that breast cancer patients after whole breast radiotherapy may experience skin dryness, hypersensitivity and hyper pigmentation in the irradiated skin area. These "radiation-irritated skin" lesions may induce depressive psychological status and impact the quality of life in breast cancer patients after whole breast radiotherapy.

2.
Sensors (Basel) ; 21(5)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804324

RESUMO

Traditional co-word networks do not discriminate keywords of researcher interest from general keywords. Co-word networks are therefore often too general to provide knowledge if interest to domain experts. Inspired by the recent work that uses an automatic method to identify the questions of interest to researchers like "problems" and "solutions", we try to answer a similar question "what sensors can be used for what kind of applications", which is great interest in sensor- related fields. By generalizing the specific questions as "questions of interest", we built a knowledge network considering researcher interest, called bipartite network of interest (BNOI). Different from a co-word approaches using accurate keywords from a list, BNOI uses classification models to find possible entities of interest. A total of nine feature extraction methods including N-grams, Word2Vec, BERT, etc. were used to extract features to train the classification models, including naïve Bayes (NB), support vector machines (SVM) and logistic regression (LR). In addition, a multi-feature fusion strategy and a voting principle (VP) method are applied to assemble the capability of the features and the classification models. Using the abstract text data of 350 remote sensing articles, features are extracted and the models trained. The experiment results show that after removing the biased words and using the ten-fold cross-validation method, the F-measure of "sensors" and "applications" are 93.2% and 85.5%, respectively. It is thus demonstrated that researcher questions of interest can be better answered by the constructed BNOI based on classification results, comparedwith the traditional co-word network approach.

3.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(2): 153-158, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-33825373

RESUMO

Electronic endoscope is one of the crucial tools for minimally invasive diagnosis and treatment. Along with the continuous development of clinical applications, conventional electronic endoscope has not been able to meet all the clinical requirements. In recent years, with the rapid development of the material, sensor and electronic technologies, electronic endoscope has attracted many researchers and companies' attention. Nowadays, because of being suitable for some special mobile medical scenes like field operations, natural calamities and hospital first aids, various portable electronic endoscopes have been developed and applied in clinic. The present study aims to give a review on portable electronic endoscopes development and clinical applications.


Assuntos
Eletrônica , Endoscópios
4.
J Am Heart Assoc ; 10(7): e015292, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33728933

RESUMO

Background Small intestinal bacterial overgrowth (SIBO) is a common pathological condition of intestinal microbiota. The prevalence of SIBO and its prognostic value in patients with heart failure (HF) are unknown. Methods and Results A total of 287 patients tested for SIBO using lactulose hydrogen-methane breath test were evaluated. At least 1 of the following criteria fulfilled was SIBO positive: patients with fasting hydrogen level ≥20 parts per million (ppm) or a ≥20 ppm rise in hydrogen by 90 minutes were diagnosed with SIBO (H2) positive; and patients with methane levels ≥10 ppm at any test point were diagnosed with SIBO (CH4) positive. The association between SIBO and the composite of cardiovascular death and HF rehospitalization was investigated. In 287 consecutive patients with HF, 128 (45%) were positive for SIBO. Our result showed SIBO increased the risk of HF rehospitalization in patients with HF with reduced ejection fraction (P<0.001), and the risk of cardiovascular death in patients with HF with preserved EF (P=0.011). SIBO was an independent risk factor of primary end point in patients with HF (hazard ratio [HR], 2.13; 95% CI; 1.26-3.58; P=0.005). In addition, SIBO (CH4) showed a prognostic value on adverse outcomes (HR, 2.35; 95% CI, 1.38-4.02; P<0.001), whereas the association between SIBO (H2) and outcomes was not statistically significant. Conclusions There was high prevalence of SIBO in patients with HF, and SIBO was independently associated with poor outcomes. Proactive treatment for SIBO may provide extra benefit for patients with HF.

5.
Cancer Sci ; 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33728743

RESUMO

The microRNAs (miRNAs) in circulating small extracellular vesicles (sEVs) have been suggested as potential biomarkers in cancer diagnosis. This study was designed to evaluate the circulating sEV-derived miRNAs as biomarkers for the diagnosis of nasopharyngeal carcinoma (NPC). We compared the miRNA profiles in plasma-derived sEVs between 16 patients with NPC and 5 healthy controls (HCs). A distinct set of miRNAs that were differentially expressed between patients with NPC and HCs was determined by means of integrative bioinformatics approaches. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment pathway analysis revealed that the target genes of the differentially expressed miRNAs (DEMs) were mainly involved in cancer-associated signaling pathways. Seven representative DEMs were selected and further validated in an additional 60 patients with NPC and 40 HCs using quantitative reverse-transcription PCR analysis (qRT-PCR). Receiver operating characteristic (ROC) curve analysis was used to assess the accuracy of the sEV-miRNA-based model for diagnosis. The 3 miRNA-based model, comprising miR-134-5p, miR-205-5p, and miR-409-3p, showed good discriminating power with an area under the curve (AUC) value of 0.88 in the training set and 0.91 in the validation set. Furthermore, the diagnostic model had an excellent classification ability to distinguish patients with NPC at different clinical stages or Epstein-Barr virus infection status from HCs. In conclusion, our findings indicated that sEV-derived miRNA levels were altered in the plasma of patients with NPC in comparison with those in HCs. The model based on the 3 sEV-derived miRNAs could potentially act as an alternative or complementary approach for diagnosing NPC.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33728612

RESUMO

PURPOSE: We aimed (1) to determine the molecular diagnosis rate and the recurrent causative genes of patients with non-obstructive azoospermia (NOA) using targeted next-generation sequencing (NGS) panel screening and (2) to discuss whether these genes help in the prognosis for microsurgical testicular sperm extraction (micro-TESE). METHODS: We used NGS panels to screen 668 Chinese men with NOA. Micro-TESE outcomes for six patients with pathogenic mutations were followed up. Functional assays were performed for two NR5A1 variants identified: p.I224V and p.R281C. RESULTS: Targeted NGS panel sequencing could explain 4/189 (2.1% by panel 1) or 10/479 (2.1% by panel 2) of the patients with NOA after exclusion of karyotype abnormalities and Y chromosome microdeletions. Almost all mutations detected were newly described except for NR5A1 p.R281C and TEX11 p.M156V. Two missense NR5A1 mutations-p.R281C and p.I244V-were proved to be deleterious by in vitro functional assays. Mutations in TEX11, TEX14, and NR5A1 genes are recurrent causes of NOA, but each gene explains only a very small percentage (less than 4/668; 0.6%). Only the patient with NR5A1 mutations produced viable spermatozoa through micro-TESE, but other patients with TEX11 and TEX14 had poor micro-TESE prognoses. CONCLUSIONS: A targeted NGS panel is a feasible diagnostic method for patients with NOA. Because each gene implicated explains only a small proportion of such cases, more genes should be included to further increase the diagnostic rate. Considering previous reports, we suggest that only a few genes that are directly linked to meiosis can indicate poor micro-TESE prognosis, such as TEX11, TEX14, and SYCE1.

7.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(1): 81-87, 2021 Feb 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33723941

RESUMO

OBJECTIVES: A study was conducted to investigate the molecular mechanism of chromodomain helicase/ATPase DNA binding protein 1-like gene (CHD1L) influencing the invasion and metastasis of tongue squamous cell carcinoma and to provide a new target for clinical inhibition of invasion and metastasis of tongue squamous cell carcinoma. METHODS: Ualcan website was used to analyze the expression of CHD1L in normal epithelial tissue and primary head and neck squamous cell carcinoma and to analyze the effect of lymph node metastasis on the expression of CHD1L in tissues with head and neck squamous cell carcinoma. The relationship between CHD1L expression and the survival rate of patients with head and neck squamous cell carcinoma was tested by the GEPIA website. Western blot was used to quantify the levels of CHD1L protein in human tongue squamous cell carcinoma CAL27 and immortalized human skin keratinocyte cell HaCaT. After knocking down CAL27 in human tongue squamous cell carcinoma cells with an RNA interference plasmid, the cells were designated as SiCHD1L/CAL27 and Scr/CAL27. Western blot was utilized to detect the expression of CHD1L in each group of cells. The change in CAL27 cell proliferation ability was tested by EdU proliferation test after CHD1L knockdown. The change of cell migration ability of each group cells was tested through the wound healing assay. Western blot was used to detect epithelial-mesenchymal transition (EMT) marker E-cadherin and Vimentin protein expression levels. RESULTS: Ualcan database showed that the expression of CHD1L in primary head and neck squamous cell carcinoma tissues was higher than in normal epithelial tissues and in head and neck squamous cell carcinoma tissues with lymph node metastasis. GEPIA website analysis showed that the overall survival rate of patients with head and neck squamous cell carcinoma with high expression of CHD1L was significantly lower than that of patients with low expression. Western blot results showed that CHD1L expression in human tongue squamous carcinoma cells CAL27 was higher than that of human normal skin cells HaCaT. CHD1L expression in SiCHD1L/CAL27 cells was much lower than that in Scr/CAL27 cells. Results of EdU proliferation experiments showed the significant reduction in the cell proliferation ability of the SiCHD1L/CAL27 cells. Results of the wound healing experiments showed the reduction in the migration capacity of the SiCHD1L/CAL27 cells. The expression of E-cadherin increased, whereas that of Vimentin decreased, in SiCHD1L/CAL27 cells. CONCLUSIONS: CHD1L promoted the EMT, proliferation, migration, and invasion ability of tongue squamous cell carcinoma cells.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias da Língua , Adenosina Trifosfatases , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , DNA Helicases , Proteínas de Ligação a DNA , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica/genética , Língua , Neoplasias da Língua/genética
8.
J Cardiovasc Pharmacol ; 77(3): 408-417, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662981

RESUMO

ABSTRACT: Promoting angiogenesis is a critical treatment strategy for ischemic cardiovascular diseases. Shexiang Baoxin Pill (SBP), a traditional Chinese medicine, has been reported to be capable of relieving angina and improve heart function by promoting angiogenesis. The aim of this study was to determine the role of mitochondrial aldehyde dehydrogenase 2 (ALDH2) in SBP-induced angiogenesis. Left femoral artery ligation was performed in wild-type mice (WT) and ALDH2 knockout mice, which were administrated with SBP (20 mg/kg/d) or equal volume saline per day by gastric gavage for 2 weeks. Perfusion recovery, angiogenesis in chronic hind limb ischemia, was significantly improved in the WT + SBP group than in the WT group. However, these beneficial effects were absent in ALDH2 knockout mice. In vitro, hypoxia impaired the ability of proliferation, migration and tube formation, sprouting angiogenesis, and promoted apoptosis in cardiovascular microvascular endothelial cells, whereas the hypoxia damage was restored by SBP. The protective effect of SBP was remarkably weakened by ALDH2 knockdown. Furthermore, SBP suppressed hypoxia-induced ALDH2/protein kinase B (AKT)/mammalian target of rapamycin pathways. In conclusion, this study demonstrated that SBP protected lower limb from ischemia injury through the ALDH2-dependent pathway. The protective mechanism of SBP in cardiovascular microvascular endothelial cells was partly mediated through ALDH2/AKT/mammalian target of rapamycin pathways.

9.
Anal Bioanal Chem ; 413(9): 2543-2551, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33576855

RESUMO

The concentration level of cytokeratin fragment antigen 21-1 (CYFRA21-1) can be used as an important indicator for predicting non-small cell lung cancer (NSCLC). Here, a sandwich-type electrochemical immunosensor for ultrasensitive detection of CYFRA21-1 is developed. The sensor based on a combination of gold nanoparticle (AuNPs) decorated Ti3C2Tx-MXene (Au-Ti3C2Tx) as the substrate enhancer, and toluidine blue (TB) modified AuNPs doped covalent organic framework (COF) polymer as the signal tag (TB-Au-COF). The Au-Ti3C2Tx is used to capture numerous primary antibodies and accelerate the electron transfer rate of the substrate, while the TB-Au-COF can be applied to provide a large number of signal units TB and secondary antibodies. These features of composites endow the proposed immunosensor with high sensitivity and current response to CYFRA21-1. Under optimum conditions, the immunosensor offers a wide current response for CYFRA21-1 from 0.5-1.0 × 104 pg·mL-1 with a detection limit of 0.1 pg·mL-1. Furthermore, the biosensing platform can be applied for CYFRA21-1 detection to analyze real serum samples, providing an effective and useful avenue for the applicability of Au-Ti3C2Tx and TB-Au-COF composite materials in biosensing field.

11.
Chemosphere ; 272: 129907, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33601207

RESUMO

BACKGROUND: Exposure to single air pollutant and physical activity (PA) were associated with an altered mitochondrial DNA copy number (mtDNA-CN). However, studies on the interactive effects of single or a mixture of air pollutants and PA on mtDNA-CN were limited. METHODS: A total of 2707 Chinese adults were obtained from the Henan Rural Cohort Study. Spatiotemporal models were used to estimate particulate matter (PMs) (PM with an aerodynamic diameter ≤ 1.0 µm (PM1), ≤2.5 µm (PM2.5) or ≤ 10 µm (PM10)) and nitrogen dioxide (NO2) concentrations. Relative mtDNA-CN was measured by quantitative real-time polymerase chain reaction. Linear regression and quantile g-computation models were applied to examine associations of single or mixture of air pollutants with relative mtDNA-CN. The interactive effects of single or mixture of air pollutants and PA on relative mtDNA-CN were visualized by using Interaction plots. RESULTS: Each 1 µg/m3 increment in PM1, PM2.5, PM10 or NO2 was associated with a 5.11% (95% confidence interval: 3.71%, 6.53%), 6.77% (4.81%, 8.76%), 3.05% (2.22%, 3.87%) or 4.99% (3.45%, 6.55%) increase in relative mtDNA-CN. Each one-quartile increment in mixture of the four air pollutants was related to a 0.053 (0.032, 0.075) increase in relative mtDNA-CN. Negative interaction effects of single or mixture of air pollutants and PA on relative mtDNA-CN were observed. CONCLUSIONS: The positive associations of single or mixture of air pollutants with relative mtDNA-CN were counteracted by PA at certain levels, implying that PA may be a costless and effective approach to decrease negative effects of air pollution on mtDNA-CN.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Adulto , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , China , Estudos de Coortes , Variações do Número de Cópias de DNA , DNA Mitocondrial/genética , Exposição Ambiental/análise , Exercício Físico , Humanos , Dióxido de Nitrogênio/análise , Material Particulado/análise
12.
J Med Virol ; 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33590892

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is recognized as an emerging infectious disease. This study aimed to investigate the pathogenic mechanism of SFTS. A total of 100 subjects were randomly included in the study. Cytokine levels were detected by enzyme-linked immunosorbent assay and the viral load was detected by micro drop digital PCR. The results showed that levels of interleukin-6 (IL-6), IL-8, IL-10, IFN-inducible protein-10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), transforming growth factor-ß1 (TGF-ß1), and regulated upon activation normal T cell expressed and secreted factor (RANTES) differed significantly among the SFTS patient group, healthy people group, and asymptomatic infection group (p < .05). Compared to the healthy people group, the patient group had increased cytokine levels (IL-6, IL-10, IP-10, MCP-1, and IFN-γ) but reduced levels of IL-8, TGF-ß1, and RANTES (p < .0167). IL-6, IL-8, IL-10, IP-10, MCP-1, MIP-1α, TGF-ß1, and the RANTES levels had different trends after the onset of the disease. IL-6, IL-10, IP-10, and MCP-1 levels in severe patients were higher than those in mild patients (p < .05). There was a positive correlation between viral load and IL-6 and IP-10 but a negative correlation between viral load and RANTES. SFTSV could cause a cytokine change: the cytokine levels of patients had different degrees of fluctuation after the onset of the disease. The levels of IL-6 and IL-8 in the asymptomatic infection group were found between the SFTS patients group and the healthy people group. The levels of IL-6, IL-10, IP-10, and MCP-1 in the serum could reflect the severity of the disease, and the levels of IL-6, IP-10, and RANTES were correlated with the viral load.

13.
Sci Total Environ ; 776: 145834, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33640545

RESUMO

BACKGROUND: Although long-term exposure to higher air pollutants and lower residing greenness related to disorders of glucose homeostasis have been reported, their interaction effects on glucose homeostasis in developing countries remained unclear. METHODS: A total of 35, 482 participants were obtained from the Henan Rural Cohort (n = 39, 259). Exposure to air pollutants (PM1, PM2.5, PM10 and NO2) were predicted by using a spatiotemporal model-based on satellites data. Residing greenness was reflected by Enhanced Vegetation Index (EVI) and Normalized Difference Vegetation Index (NDVI) which were derived from satellites data. Independent associations of single or mixture of air pollutant or residing greenness with glucose homeostasis markers were analyzed by quantile regression models and quantile g (qg)-computation method, respectively. Furthermore, interaction effects of residing greenness and air pollution on glucose homeostasis markers were analyzed by generalized additive models. RESULTS: Positive associations of single or mixture of air pollutants (PM1, PM2.5, PM10 or NO2) with fasting plasma glucose (FPG) were observed, while negative associations of single or mixture of air pollutants with insulin or HOMA-ß were observed. Residing greenness was negatively associated with FPG but positively related to insulin or HOMA-ß. Quantile regression revealed the heterogeneity were observed in the associations the residing greenness or air pollutants with glucose homeostasis markers (insulin or HOMA-ß) across deciles of the glucose homeostasis markers distributions. Furthermore, joint associations of single air pollutant and residing greenness on glucose homeostasis markers were found. CONCLUSIONS: The results indicated that exposure to air pollution had negative effect on glucose homeostasis markers and these effects may be modified by living in higher green space. These findings suggest that increased residing greenness and air pollution control may have joint effect on decreased the risk of diabetes. CLINICAL TRIAL REGISTRATION: The Henan Rural Cohort study has been registered at Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699, http://www.chictr.org.cn/showproj.aspx?proj=11375).

15.
Innate Immun ; 27(2): 201-209, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33576722

RESUMO

Increasing evidence indicates that signal transducer and activator of transcription 3 (STAT3), a vital transcription factor, plays crucial roles in the regulation of inflammation. STAT3 has become a novel therapeutic target for intervention in inflammation-related disorders. However, it remains unclear whether STAT3 plays a part in acute hepatic damage. To investigate the effects of STAT3 here, LPS/d-GalN-induced hepatic damage was induced in mice, the STAT3 inhibitor Stattic was administered, and the degree of liver injury, inflammation, and hepatocyte apoptosis were investigated. The results showed that Stattic mitigated the hepatic morphologic abnormalities and decreased the level of aminotransferase in LPS/D-GalN-insulted mice. The results also indicated that Stattic decreased the levels of TNF-α and IL-6, prevented the activation of the caspase cascade, suppressed cleavage of PARP, and decreased the quantity of TUNEL-positive cells. These results suggest that Stattic provided protective benefits in LPS/d-GalN-induced hepatic damage, and the protective effects might be associated with its anti-inflammatory and anti-apoptotic effects. Therefore, STAT3 might become a novel target for intervening in inflammation-based and apoptosis-based hepatic disorders.

17.
Fertil Steril ; 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33487443

RESUMO

OBJECTIVE: To investigate the association of endometrium preparation with perinatal outcomes. DESIGN: Retrospective cohort study. SETTING: University-affiliated fertility center. PATIENT(S): Twenty-one thousand six hundred and forty-eight women who underwent frozen single-blastocyst transfer from January 2013 to March 2019. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Cesarean delivery, preterm delivery (PTD), vaginal PTD, very preterm delivery (VPTD), postterm delivery, low birth weight (LBW), macrosomia, small for gestational age (SGA), large for gestational age (LGA), hypertensive disorders of pregnancy (HDP), gestational diabetes mellitus (GDM), premature rupture of membrane (PROM), placenta previa, and congenital abnormality. RESULT(S): Compared with natural cycles, hormone replacement cycles were associated with an increased risk of PTD, VPTD, cesarean delivery, macrosomia, PROM, and HDP. There was a trend toward an increased risk of vaginal PTD and LGA in hormone replacement cycles. Stimulated cycles were associated with an increased risk of postterm delivery and GDM. There was no statistically significant difference in the rate of SGA, placenta previa, or congenital abnormality among the three endometrium preparation methods. CONCLUSION(S): Hormone replacement cycles are associated with an increased risk of PTD, VPTD, cesarean delivery, LBW, macrosomia, PROM, and HDP. Stimulated cycles are associated with an increased risk of postterm delivery and GDM.

18.
Clin Oral Investig ; 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33432420

RESUMO

OBJECTIVES: The aim of this study was to assess whether alveolar ridge preservation (ARP) can reduce the need of ridge augmentation at posterior tooth sites. MATERIAL AND METHODS: This study enrolled patients who received dental implants at posterior tooth sites during 2013-2019. Demographic data and dental treatment histories were collected. Based on healing patterns after tooth extraction, patients were divided into ARP and spontaneous healing (SH) groups. Three surgical treatment plans were devised according to the alveolar bone volume on cone-beam computed tomography (CBCT). The three treatment plans were to perform implant alone, simultaneous guided bone regeneration (GBR) and implantation, and staged GBR before implantation. Statistical analyses were performed to determine relationships. RESULTS: There were 92 implant records in the ARP group and 249 implant records in the SH group. A significant intergroup difference was observed regarding the frequency distribution of the treatment modality of staged GBR before implant (χ 2 = 15.07, p = 0.0005). Based on the implant alone treatment modality and simple logistic regression, the SH pattern was related to staged GBR before implant (SH vs. ARP: crude odds ratio (OR) = 4.65, 95% confidence interval (CI) = 2.15-11.61, p = 0.0003). After adjusting confounding factors, the risk was still significant (adjusted OR = 5.02, 95% CI = 2.26-12.85, p = 0.0002). CONCLUSIONS: The study results suggested that ARP is more likely to lead to the treatment modality of implant alone and reduce the need for staged GBR before implantation. CLINICAL RELEVANCE: This study describes ARP capable of minimizing the need for staged GBR before implantation and shortening the treatment duration.

19.
Proc Natl Acad Sci U S A ; 118(4)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33468680

RESUMO

In biosynthesis of the pancreatic cancer drug streptozotocin, the tridomain nonheme-iron oxygenase SznF hydroxylates N δ and N ω' of N ω-methyl-l-arginine before oxidatively rearranging the triply modified guanidine to the N-methyl-N-nitrosourea pharmacophore. A previously published structure visualized the monoiron cofactor in the enzyme's C-terminal cupin domain, which promotes the final rearrangement, but exhibited disorder and minimal metal occupancy in the site of the proposed diiron cofactor in the N-hydroxylating heme-oxygenase-like (HO-like) central domain. We leveraged our recent observation that the N-oxygenating µ-peroxodiiron(III/III) intermediate can form in the HO-like domain after the apo protein self-assembles its diiron(II/II) cofactor to solve structures of SznF with both of its iron cofactors bound. These structures of a biochemically validated member of the emerging heme-oxygenase-like diiron oxidase and oxygenase (HDO) superfamily with intact diiron cofactor reveal both the large-scale conformational change required to assemble the O2-reactive Fe2(II/II) complex and the structural basis for cofactor instability-a trait shared by the other validated HDOs. During cofactor (dis)assembly, a ligand-harboring core helix dynamically (un)folds. The diiron cofactor also coordinates an unanticipated Glu ligand contributed by an auxiliary helix implicated in substrate binding by docking and molecular dynamics simulations. The additional carboxylate ligand is conserved in another N-oxygenating HDO but not in two HDOs that cleave carbon-hydrogen and carbon-carbon bonds to install olefins. Among ∼9,600 sequences identified bioinformatically as members of the emerging HDO superfamily, ∼25% conserve this additional carboxylate residue and are thus tentatively assigned as N-oxygenases.

20.
Dalton Trans ; 50(6): 2093-2101, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33481974

RESUMO

Highly efficient bifunctional oxygen electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are crucially important for the rechargeable Zn-air battery, a potential power source for applications in electric vehicles and grid-scale stationary storage systems. Herein, Co3O4@NiCo2O4 double-shelled nanocages (Co3O4@NiCo2O4 DSNCs) with hierarchical hollow structure and oxygen vacancies were designed and synthesized via annealing metal-organic frameworks. Co3O4@NiCo2O4 DSNCs with large specific surface area and three-dimensional interconnected mesopores and cavity not only provide more reaction sites, but also offer an efficient transport environment for reactants. Moreover, oxygen vacancies on the surfaces improve the capture of oxygen species to enhance the reactivity of the catalyst. Consequently, Co3O4@NiCo2O4 DSNCs displayed excellent bifunctional electrocatalytic performance, with a positive half-wave potential of 0.81 V (vs. reversible hydrogen electrode, RHE) for ORR (approaching the potential of commercial Pt/C catalyst) and a low potential of 1.65 V at 10 mA cm-2 for OER (exceeding Pt/C). In a practical demonstration, the Zn-air battery using Co3O4@NiCo2O4 DSNCs as the cathode delivered a satisfactory power density of 102.1 mW cm-2, comparable to the Zn-air battery with a Pt/C cathode, and exhibited much longer cycling stability.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...