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1.
J Cardiothorac Surg ; 15(1): 87, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398043

RESUMO

BACKGROUND: Pulmonary artery aneurysm (PAA), usually associated with congenital heart disease (CHD), is a very rare clinical condition. Pulmonary artery dissection (PAD) is considered the most life-threatening complication of PAA, and patients can progress from being asymptomatic to sudden death. We report the following case of PAA associated with complicated congenital heart disease and simultaneous chronic PAD. To our knowledge, few such complicated cases have ever been reported. CASE PRESENTATION: A 36-year-old male presented to our hospital with a 10-year history of heart fatigue after activities and aggravated for 2 years. Computed tomography angiography (CTA) and echocardiogram showed a giant main pulmonary artery aneurysm (14 cm) with complicated congenital heart disease (a small patent ductus arteriosus, ventricular septal defects, aortic coarctation). Chronic PAD, which was mistaken for a pulmonary valve before operation, was detected during surgery. CONCLUSIONS: PAA associated with complicated CHD and simultaneous PAD is very rare, and its clinical symptoms are varied. Radiologists and surgeons should pay attention to determining whether this patient simultaneously had PAD when PAA was detected on preoperative CTA imaging.

2.
BMC Nephrol ; 21(1): 159, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366263

RESUMO

BACKGROUND: Mesoamerican nephropathy (MeN) is a pattern of chronic kidney disease (CKD) prevalent among Central American men who work in agriculture, and its underlying cause has not been elucidated. Currently, experts hypothesize that MeN is related to repeated episodes of occupational heat stress leading to water loss and hence it is also called dehydration-associated CKD. CASE PRESENTATION: We report a case of a 40-year-old man, whose first admission to Peking Union Medical College Hospital was due to acute kidney injury (AKI). The clinical and pathological processes were consistent with acute tubular necrosis (ATN). However, after full recovery, CKD developed 1 year later. The second renal biopsy showed characteristics of ischemic renal disease but there was no evidence of vascular disease. It is worth noting that the patient had been taking part in long-distance running without drinking adequate water for years, which would have markedly decrease his renal blood flow. Thus, this patient may have developed chronic dehydration-associated kidney disease sharing the similar etiology of MeN. CONCLUSIONS: We report here a case of dehydration-associated CKD in a Chinese patient which shared similar etiology to MeN. Even in non-agricultural areas, this etiology of CKD should be noted to obtain a relevant history and prompt diagnosis.

3.
J Chem Phys ; 152(17): 174307, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32384849

RESUMO

A Feshbach optimized photoassociation (FOPA) process for preparing ultracold excited-state 39K133Cs molecules is studied theoretically. Under the joint action of the magnetic field and short laser pulse, the colliding atoms in a superposition state composed of eight hyperfine components are converted into a molecule in the vibrational level of the excited state via two transition processes, the transition between singlet states and the transition between triplet states. The association efficiency can be significantly enhanced by taking advantage of Feshbach resonance. At different resonance positions, different hyperfine components of the superposition state dominate over the FOPA process, and the quantum interference displays different behaviors. Compared with the FOPA process only including a single hyperfine component, the quantum interference in the FOPA process containing all hyperfine components has a visible effect on the association efficiency.

4.
Environ Int ; 140: 105762, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32380304

RESUMO

OBJECTIVE: Telomere is required for maintaining chromosome stability and genome integrity, while telomere length is sensitive to environmental stressors. We aimed to identify the effects of multiple metals co-exposure as well as their joint effects with TERT-CLPTM1L variants on leukocyte telomere length (LTL). METHODS: This study included 842 workers from a coke-oven plant, of whom plasma concentrations of 23 metals and LTL were determined. Genetic variations in TERT-CLPTM1L were genotyped by using the Global Screening Array. Multipollutant-based statistical methods, including the Bonferroni-correction, backward elimination procedure, and LASSO penalized regression analysis, were used to select the LTL-associated metals. Generalized linear regression models were used to evaluate the joint effects of TERT-CLPTM1L variants with positive metal on LTL. RESULTS: Each 1% increase in plasma concentration of manganese (Mn) was significantly associated with a 0.153% increase in LTL [ß(95%CI) = 0.153(0.075, 0.230), P < 0.001] in single-metal models after Bonferroni-correction. The multiple-metal models and the LASSO penalized regression analysis both indicated Mn as the sole significant predictor for LTL. Furthermore, 5 tagSNPs (rs33954691, rs6554759, rs465498, rs2455393, and rs31489) in TERT-CLPTM1L with high plasma Mn (>4.21 µg/L) showed joint effects on increasing LTL. CONCLUSIONS: Our study revealed the independent and positive association between plasma Mn and LTL when accounting for co-exposure to other metals. This effect can be further enhanced by TERT-CLPTM1L variants. These results may advance our understanding of the complex interplay between genetic and environmental factors on telomere length. Further experimental studies are warranted to elucidate the underlying mechanisms.

5.
Biomed Pharmacother ; 127: 110183, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32388241

RESUMO

Src family kinases (SFKs) is a non-receptor protein tyrosine kinases family. They are crucial in signal transduction and regulation of various cell biological processes, such as proliferation, differentiation and apoptosis. The role and mechanism of SFKs in tumorigenesis have been widely studied. However, more and more studies have also shown that SFKs are involved in the pathogenesis of pulmonary fibrosis (PF). Myofibroblasts activation, epithelial-mesenchymal transition and inflammation response are three pivotal pathomechanisms in the development of pulmonary fibrotic disease. In this article, we summarize the roles of SFKs in these biological processes. SFKs play a crucial role in the pathogenesis of PF, making it a promising molecular target for the treatment of these diseases. We will pay special attention to the role of SFKs in idiopathic pulmonary fibrosis (IPF), and also emphasize the important findings in other pulmonary fibrotic diseases because their pathological mechanisms are similar. We will then describe the translation results obtained with SFKs inhibitors in basic and clinical studies.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32418614

RESUMO

BACKGROUND: Renal Fanconi syndrome (FS) is rare in primary SjÓ§gren's syndrome (pSS). We aimed to describe the clinicopathological characteristics of pSS associated FS (pSS-FS) and its responses to treatment. METHODS: We reported 25 cases of pSS-FS patients and retrospectively reviewed their clinical records, kidney pathology and follow-up data. RESULTS: The 25 pSS-FS patients were mainly female (92.0%) and the mean age at diagnosis was 43.6±11.3 years. They showed different degrees of proximal tubular dysfunctions and eGFR decline (60.9±32.3 ml/min/1.73m2). Kidney pathology of pSS-FS patients showed tubulo-interstitial nephritis with defective brush border and lymphoplasmacytic infiltrates. After glucocorticoid treatment, the eGFR levels were significantly improved from 48.3±20.6 ml/min/1.73m2 to 55.0±19.9 ml/min/1.73m2 (P = 0.012) at the third month of follow-up. They also acquired good tubular (88.2%) and immunological (90.0%) responses. pSS-FS patients with young-onset pSS presented with a higher prevalence of positive anti-SSB antibody and hypocomplementemia, more severe hypokalemia, and better eGFR levels. CONCLUSIONS: In pSS-FS patients, use of glucocorticoids could improve eGFR and tubular functions. The young-onset pSS group presented with a particular pattern in immunological features and kidney involvement.

7.
Opt Express ; 28(8): 10794-10805, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32403603

RESUMO

The compound eye of insects has many excellent characteristics. Directional navigation is one of the important features of compound eye, which is able to quickly and accurately determine the orientation of an objects. Therefore, bionic curved compound eye have great potential in detecting the orientation of the target. However, there is a serious non-linear relationship between the orientation of the target and the image obtained by the curved compound eye in wide field of view (FOV), and an effective model has not been established to detect the orientation of target. In this paper, a method for detecting the orientation of the target is proposed, which combines a virtual cylinder target with a neural network. To verify the feasibility of the method, a fiber-optic compound eye that is inspired by the structure of the bee's compound eye and that fully utilizes the transmission characteristics and flexibility of optical fibers is developed. A verification experiment shows that the proposed method is able to realize quantitative detection of orientations using a prototype of the fiber-optic compound eye. The average errors between the ground truth and the predicted values of the horizontal and elevation angles of a target are 0.5951 ° and 0.6748°, respectively. This approach has great potential for target tracking, obstacle avoidance by unmanned aerial vehicles, and directional navigation control.

8.
Thorac Cancer ; 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32374522

RESUMO

BACKGROUND: Breast cancer (BRCA) is the leading cause of cancer-related death in women worldwide. Pre- and postoperative radiotherapy play a pivotal role in BRCA treatment but its efficacy remains limited and plagued by the emergence of radiation resistance, which aggravates patient prognosis. The long noncoding RNA (lncRNA)-implicated mechanisms underlying radiation resistance are rarely reported. The aim of this study was to determine whether lncRNA HOX transcript antisense RNA (HOTAIR) modulated the radiosensitivity of breast cancer through HSPA1A. METHODS: A Gammacell 40 Exactor was used for irradiation treatment. Bioinformatic tools and luciferase reporter assay were adopted to explore gene expression profile and demonstrate the interactions between lncRNA, miRNA and target mRNA 3'-untranslated region (3'-UTR). The expression levels of certain genes were determined by real-time PCR and western-blot analyses. in vitro and in vivo functional assays were conducted by cell viability and tumorigenicity assays. RESULTS: The levels of oncogenic lncRNA HOTAIR were positively correlated with the malignancy of BRCA but reversely correlated with the radiosensitivity of breast cancer cells. Moreover, the expression levels of HOTAIR were positively associated with those of heat shock protein family A (Hsp70) member 1A (HSPA1A) in clinical BRCA tissues and HOTAIR upregulated HSPA1A at the mRNA and protein levels in irradiated BRCA cells. Mechanistically, miR-449b-5p restrained HSPA1A expression through targeting the 3'-UTR of HSPA1A mRNA, whereas HOTAIR acted as a competing sponge to sequester miR-449b-5p and thereby relieved the miR-449b-5p-mediated HSPA1A repression. Functionally, HOTAIR conferred decreased radiosensitivity on BRCA cells, while miR-449b-5p overexpression or HSPA1A knockdown abrogated the HOTAIR-enhanced BRCA growth under the irradiation exposure both in vitro and in vivo. CONCLUSIONS: LncRNA HOTAIR facilitates the expression of HSPA1A by sequestering miR-449b-5p post-transcriptionally and thereby endows BRCA with radiation resistance. KEY POINTS: Therapeutically, HOTAIR and HSPA1A may be employed as potential targets for BRCA radiotherapy. Our findings shed new light into the mechanism by which lncRNAs modulate the radiosensitivity of tumors.

10.
Eur Radiol ; 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32356159

RESUMO

OBJECTIVES: To evaluate the clinical efficacy of microwave ablation (MWA) of benign breast lesions (BBLs) and compare the learning curves of international radiologists (IRs) and surgeons. METHODS: In total, 440 patients with 755 clinicopathologically confirmed BBLs from 5 centers were prospectively enrolled from February 2014 to July 2018. Technical success, complications, volume reduction ratio (VRR), palpability, and cosmetic satisfaction after ablation were analyzed. In addition, the ablation time (AT) and energy (AE) with the number of procedures were analyzed for learning curve evaluation. RESULTS: The mean maximum diameter was 1.7 ± 0.6 cm. The complete ablation rate reached 100%, including 45.8% lesions adjacent to the skin, pectoralis, or areola. After a median follow-up of 13.7 months, the 12-month VRR of all lesions was 97.9%, and that for 1.0- to 2.0-cm and ≥ 2.0-cm lesions was 98.6% and 96.9%, respectively. A total of 55.9% of BBLs became nonpalpable (palpable in 85.7% of cases before MWA) by both the clinician and patient. The cosmetic and minimally invasive satisfaction rates were good or excellent in 98.4% and 94.5% of patients, respectively. The median AT/cm3 and AE/cm3 decreased as experience increased. The AE/cm3 of the IR with 5 years of experience was lower than that of the IR with 1 year of experience and the surgeons, while the AT/cm3 of surgeons was comparable with that of the IR with 5 years of experience at relatively mature phase. CONCLUSIONS: Ultrasound-guided percutaneous MWA is a valuable technique for the treatment of BBLs. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02860104) KEY POINTS: • Ultrasound-guided percutaneous microwave ablation has the potential to become a valuable technique for the treatment of benign breast lesions. • A skilled interventional radiologist shows a rapid improvement in mastering the technique.

11.
J Healthc Eng ; 2020: 1051394, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32399163

RESUMO

Medical data have the characteristics of particularity and complexity. Big data clustering plays a significant role in the area of medicine. The traditional clustering algorithms are easily falling into local extreme value. It will generate clustering deviation, and the clustering effect is poor. Therefore, we propose a new medical big data clustering algorithm based on the modified immune evolutionary method under cloud computing environment to overcome the above disadvantages in this paper. Firstly, we analyze the big data structure model under cloud computing environment. Secondly, we give the detailed modified immune evolutionary method to cluster medical data including encoding, constructing fitness function, and selecting genetic operators. Finally, the experiments show that this new approach can improve the accuracy of data classification, reduce the error rate, and improve the performance of data mining and feature extraction for medical data clustering.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32361787

RESUMO

INTRODUCTION: EGFR mutations occur most frequently in patients with lung adenocarcinoma in East Asia. However, the prognostic and therapeutic impact of co-mutational status of EGFR and tumor suppressor genes is not fully understood. This study aims to provide a deeper understanding of lung adenocarcinoma patients with co-mutation of EGFR and tumor suppressor genes. METHODS: From November 2009 to May 2016, 675 patients with lung adenocarcinoma who underwent complete surgery were included in this study. Samples were collected and pathologically examined. Whole-exome sequencing was performed on 197 samples, while direct sequencing of major driver genes, including EGFR, KRAS, ERBB2 and BRAF and Ion-torrent targeted sequencing of tumor suppressor genes, including TP53, KEAP1, MGA, NF1, RB1, SMARCA4 and STK11, were performed on 478 samples. Tumor mutational burden was calculated and survival analyses were performed. RESULTS: The frequency of EGFR and TP53 mutation was 409 (60.6%) and 215 (31.9%), respectively. Co-mutation of EGFR and TP53 occured in 151 patients (22.4%), while co-mutation of EGFR and at least one tumor suppressor gene occured in 184 patients (27.3%). Compared with patients with only EGFR mutations, patients with co-mutations of EGFR and TP53 had a higher tumor mutational burden (p = 0.007) and worse recurrence-free survival (p = 0.010), while patients with co-mutations of EGFR and at least one tumor suppressor gene had a higher tumor mutational burden (p = 0.007), worse recurrence-free survival (p = 0.016) and worse overall survival (p = 0.018). CONCLUSIONS: Lung adenocarcinoma patients harboring EGFR and co-mutational tumor suppressor genes should be regarded as a unique subgroup.

13.
Biol Pharm Bull ; 43(5): 767-773, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378555

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Gentiana delavayi Franch. (Gentianaceae) as an ethnomedicinal plant contains a variety of effective active ingredients and exhibits diverse pharmacological actions, such as hepatoprotective, anti-inflammatory and central nervous system effects. In this study we investigated the influence of G. delavayi flower extract on amyloid precursor protein (APP) processing at molecular and cellular levels. APP/PS1 Chinese hamster ovary (CHO) cells were treated with chloroform extract of G. delavayi flower in different concentrations for 24 h. Concentrations of amyloid ß (Aß) 40 and Aß42 in the cell supernatant and activity of ß-site amyloid precursor protein cleaving enzyme 1 (BACE1), BACE2, and cathepsin D were determined. The expression of APP and neprilysin (NEP) within the cell were further determined. Compared with the control group, the levels of Aß40 and Aß42 declined notably and the activity of BACE1 was inhibited significantly in the APP/PS1 CHO cells after treatment with the chloroform extract of G. delavayi flower. Although the activities of BACE2 and cathepsin D were not changed, the expression of Aß degrading enzyme NEP increased remarkably. Our experiments have clearly showed that the chloroform extract of G. delavayi flower inhibits the generation of ß-amyloid by specifically inhibiting ß-secretase and increases the expression of NEP which fastens the degradation of Aß, exhibiting the effect of decreasing Aß accumulation in APP/PS1 CHO cells. These results suggest that the active components from the chloroform extract of G. delavayi flower have a further prospect to be developed as potential anti-Aß drug.

14.
J Recept Signal Transduct Res ; : 1-9, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32314642

RESUMO

Objectives: Wolf-Hirschhorn syndrome candidate gene-1 (WHSC1) is highly expressed in various malignant tumors. We investigated the correlation and regulatory pathway of WHSC1 in the progression of breast cancer (BC).Methods: The expression and distribution of WHSC1 in the BC tissues and cell lines were determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemical staining. Spearman correlation analysis demonstrated the correlation between WHSC1 high expression level and the clinical characteristics of BC patients. The effects of WHSC1 on the proliferation, apoptosis, migration and invasion of BC cells were analyzed by cell transfection, MTT, colony formation, scratch assay, and transwell. Furthermore, the expression of Forkhead box M1 (FoxM1) and the location of ß-catenin were detected by qRT-PCR and western blot.Results: Firstly, WHSC1 expression was up-regulated in BC tissues and cell lines. The high expression of WHSC1 in BC is associated with the tumor size (p = 0.027), metastasis (p = 0.018) and pathological stages (p = 0.025) of the BC patients. The knockdown of WHSC1 inhibited the growth, proliferation migration, invasion and EMT of BC cell lines. Furthermore, WHSC1 could promote the expression of FoxM1 in BC cells and tissues. WHSC1 enhanced the expression of FoxM1, and promoted the nuclear localization of ß-catenin, and thus activated the downstream genes expression of Wnt/ß-catenin signaling pathway to regulate the development of BC.Conclusion: In summary, our study elucidates the correlation and specific regulatory mechanism between WHSC1 and the progression of BC, thus implying that WHSC1 may function as molecular diagnosis, prognosis and molecular targeted therapy of BC.

15.
Ann Surg Oncol ; 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32253677

RESUMO

BACKGROUND: The clinicopathological and survival profiles across primary sites in acral melanoma (AM) are still controversial and unclear. METHODS: This is a multi-center retrospective study. Clinicopathological data of AM patients diagnosed between 1 January 2000 and 31 December 2017 from 6 large tertiary hospitals in China were extracted. Chi square tests were used to compare basic characteristics between primary sites of sole, palm and nail bed. Melanoma-specific survival (MSS) differences based on primary sites were compared by log-rank tests and multivariate Cox regressions were used to identify prognostic factors for MSS. RESULTS: In total, 1157 AM patients were included. The sole group had a more advanced initial stage, deeper Breslow thickness, higher recurrence rate and distant metastases risk (all P < 0.05). The proportion of age < 65 years and ulceration were statistically lower in nail bed and palm groups, respectively. A total of 294 patients underwent sentinel lymph node biopsy and rates of positive SLN status had no statistical difference across primary sites. Among 701 patients with genetic profiles, the mutational frequency of BRAF, C-KIT, and PDGFRA were similar except for NRAS (higher in sole group, P = 0.0102). The median MSS of sole, nail bed and palm patients were 65.0 months, 112.0 months, and not reached, respectively (log-rank P = 0.0053). In multivariate analyses, primary site, initial stage, ulceration and recurrence were the prognostic factors for MSS in overall population, but the statistical significance varied over primary sites. CONCLUSIONS: Substantial clinicopathological and survival heterogeneities exist across different primary sites in the AM population. Sole melanoma has worse prognosis compared with palm and nail bed subtypes.

16.
Parasite ; 27: 19, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32223884

RESUMO

Bovine Theileria are tick-borne protozoan parasites that invade bovine erythrocytes and lymphocytes. Three main bovine Theileria species have been identified in China: T. orientalis, T. sinensis, and T. annulata. To examine the prevalence of bovine theileriosis in Yanbian, a total of 584 bovine blood samples were collected from five localities from 2017 to 2019 and analyzed by PCR. Six pairs of oligonucleotide primers directed against the 18S rRNA gene of Theileria spp., Tams-1 gene of T. annulata, MPSP gene of T. orientalis, and T. sinensis, were used to detect these parasites. A sequence analysis of the amplified genes confirmed that the Theileria species were T. orientalis and T. sinensis, without T. annulata. The overall prevalence of Theileria in cattle was 42.81% (250/584). Out of the 584 samples, 159 (27.23%) and 157 (26.88%) were positive for T. sinensis and T. orientalis, respectively, and the mixed infection rate was 11.30% (66/584). The total prevalence of bovine Theileria species in Helong, Hunchun, Longjing, Yanji, and Dunhua was 66.28%, 49.68%, 23.81%, 28.15%, and 0%, respectively. These results provide epidemiological data for the prevention and control of bovine Theileria species in Yanbian, China.

17.
Reprod Biomed Online ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32299734

RESUMO

RESEARCH QUESTION: Is fentanyl and midazolam non-inferior to pethidine and diazepam in pain relief during oocyte retrieval under conscious sedation? DESIGN: A randomized double-blinded non-inferiority trial of 170 infertile women undergoing oocyte retrieval under conscious sedation in an assisted reproduction centre. The women were randomized to receive intravenously either 0.1 mg fentanyl and 5 mg midazolam or 25 mg pethidine and 5 mg diazepam, plus paracervical block with 10 ml 1% lignocaine. The primary outcome was abdominal pain level during retrieval assessed by linear visual analogue scale from 0-10. Secondary outcomes included vaginal pain levels during and after retrieval and postoperative abdominal pain levels and side-effects, satisfaction level, clinical pregnancy and ongoing pregnancy rates. A pre-defined non-inferiority margin of 1 for the difference in pain levels between two groups was set. RESULTS: Vaginal and abdominal pain levels during retrieval were significantly lower in the fentanyl and midazolam group compared with the pethidine and diazepam group (per-protocol analysis, vaginal pain: 1.6 versus 4.3; mean difference: -2.7, 95% CI -3.7, -1.8; P < 0.001; abdominal pain: 2.9 versus 5.2; mean difference: -2.3, 95% CI -3.3 to -1.3; P < 0.001 for non-inferiority). No differences were observed in these pain levels after retrieval. Most women experienced no postoperative side-effects. The fentanyl and midazolam group had better sedation level, satisfaction level on pain relief and satisfaction on the overall retrieval procedure than the pethidine and diazepam group. No significant differences were found in clinical pregnancy and ongoing pregnancy rates between the two groups. CONCLUSION: The fentanyl and midazolam group had significantly lower vaginal and abdominal pain levels during oocyte retrieval than the pethidine and diazepam group.

18.
Artigo em Inglês | MEDLINE | ID: mdl-32265113

RESUMO

OBJECTIVE: Randomised trials of new devices for peripheral arterial endovascular intervention are published regularly. The evidence for which antiplatelet and/or anticoagulant (antithrombotic) therapy to use after an intervention is lacking. The aim of this systematic review was to examine the antithrombotic regimens in randomised trials for peripheral arterial endovascular intervention to understand choices made and trends with time or type of device. METHODS: Data sources were the Medline, Embase, and Cochrane Library databases. Randomised trials including participants with peripheral arterial disease undergoing any endovascular arterial intervention were included. Trial methods were assessed to determine whether an antithrombotic protocol had been specified, its completeness, and the agent(s) prescribed. Antithrombotic therapy protocols were classed as peri-procedural (preceding and during intervention), immediate post-procedural (up to 30 days following intervention), and maintenance post-procedural (therapy continuing beyond 30 days). RESULTS: Ninety-four trials were included in narrative synthesis. Study quality was low. None of the trials justified their antithrombotic therapy protocol. Only 29% of trials had complete peri-procedural antithrombotic protocols, and 34% had complete post-procedural protocols. In total, 64 different peri-procedural protocols, and 51 separate post-procedural protocols were specified. Antiplatelet monotherapy and unfractionated heparin were the most common regimen choices in the peri-procedural setting, and dual antiplatelet therapy (55%) was most commonly utilised post procedure. Over time there has been an increasing tendency to use dual therapy (p < .001). This corresponds with the introduction of newer technologies and trials focussed on below knee intervention. CONCLUSION: Randomised trials comparing different types of peripheral endovascular arterial intervention have a high level of heterogeneity in their antithrombotic regimens. Antiplatelet therapy needs to be standardised in trials comparing endovascular technologies to reduce potential confounding. To do this, an independent randomised trial specifically examining antiplatelet therapy following peripheral arterial endovascular intervention is needed.

19.
Adv Mater ; 32(19): e1908314, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32239583

RESUMO

Materials possessing structural phase transformations exhibit a rich set of physical and chemical properties that can be used for a variety of applications. In 2D materials, structural transformations have so far been induced by strain, lasers, electron injection, electron/ion beams, thermal loss of stoichiometry, and chemical treatments or by a combination of such approaches and annealing. However, stoichiometry-preserving, purely thermal, reversible phase transitions, which are fundamental in physics and can be easily induced, have not been observed. Here, the fabrication of monolayer Cu2 Se, a new 2D material is reported, demonstrating the existence of a purely thermal structural phase transition. Scanning tunneling microscopy, scanning transmission electron microscopy, and density functional theory (DFT) identify two structural phases at 78 and 300 K. DFT calculations trace the phase-transition mechanism via the existence/absence of imaginary (unstable) phonon modes at low and high temperatures. In situ, variable-temperature low-energy electron diffraction patterns demonstrate that the phase transition occurs across the whole sample at ≈147 K. Angle-resolved photoemission spectra and DFT calculations show that a degeneracy at the Γ point of the energy bands of the high-temperature phase is lifted in the low-temperature phase. This work opens up possibilities for studying such phase transitions in 2D materials.

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