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1.
Chemistry ; 27(62): 15375-15381, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34536306

RESUMO

Highly π-extended butterfly-shaped triarylamine dyads with aryleneethynylene spacer were constructed using an efficient synthetic route. These aryleneethynylene-bridged dyads are highly fluorescent and exhibited high HOMO levels, and low bandgaps, which are suitable for high-performance p-type OFETs. The field-effect transistors were fabricated through a solution-processable method and exhibited promising p-type performance with field-effect mobility up to 4.3 cm2 /Vs and high Ion/off of 108 under ambient conditions.

2.
Cochrane Database Syst Rev ; 7: CD002786, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34298589

RESUMO

BACKGROUND: People with end-stage renal disease (ESRD) often require either the formation of an arteriovenous fistula (AVF) or an interposition prosthetic arteriovenous graft (AVG) for haemodialysis. These access sites should ideally have a long life and a low rate of complications (e.g. thrombosis, infection, stenosis, aneurysm formation and distal limb ischaemia). Although some of the complications may be unavoidable, any adjuvant technique or medical treatment aimed at decreasing complications would be welcome. This is the fourth update of the review first published in 2003. OBJECTIVES: To assess the effects of adjuvant drug treatment in people with ESRD on haemodialysis via autologous AVFs or prosthetic interposition AVGs. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and ClinicalTrials.gov trials register to 6 August 2020. SELECTION CRITERIA: Randomised controlled trials of active drug versus placebo in people with ESRD undergoing haemodialysis via an AVF or prosthetic interposition AVG. DATA COLLECTION AND ANALYSIS: For this update, two review authors (IM, MFAK) independently selected trials for inclusion, extracted data, assessed risk of bias and assessed the certainty of the evidence according to GRADE. We resolved disagreements by discussion or consultation with another review author (ADS). The primary outcome was the long-term fistula or graft patency rate. Secondary outcomes included duration of hospital stay; complications such as infection, aneurysm formation, stenosis and distal limb ischaemia; and number of related surgical or radiological interventions. MAIN RESULTS: For this update, one additional study was suitable for inclusion, making a total of 13 trials with 2080 participants. Overall the certainty of the evidence was low or moderate due to short follow-up periods, heterogeneity between trials, small sample sizes, and risk of bias due to incomplete reporting. Medical adjuvant treatments used in the included trials were aspirin, ticlopidine, dipyridamole, dipyridamole plus aspirin, warfarin, fish oil, clopidogrel, sulphinpyrazone and glyceryl trinitrate (GTN) patch.  All included studies reported on graft patency by measuring graft thrombosis. There was insufficient evidence to determine if there was a difference in graft patency in studies comparing aspirin versus placebo (odds ratio (OR) 0.40, 95% confidence interval (CI) 0.07 to 2.25; 3 studies, 175 participants; low-certainty evidence). The meta-analysis for graft patency comparing ticlopidine versus placebo favoured ticlopidine (OR 0.45, 95% CI 0.25 to 0.82; 3 studies, 339 participants; moderate-certainty evidence). There was insufficient evidence to determine if there was a difference in graft patency in studies comparing fish oil versus placebo (OR 0.24, 95% CI 0.03 to 1.95; 2 studies, 220 participants; low-certainty evidence); and studies comparing clopidogrel and placebo (OR 0.40, 95% CI 0.13 to 1.19; 2 studies, 959 participants; moderate-certainty evidence). Similarly, there was insufficient evidence to determine if there was a difference in graft patency comparing the effect of dipyridamole versus placebo (OR 0.46, 95% CI 0.11 to 1.94; 1 study, 42 participants, moderate-certainty evidence) and dipyridamole plus aspirin versus placebo (OR 0.64, CI 0.16 to 2.56; 1 study, 41 participants; moderate-certainty evidence); comparing low-intensity warfarin with placebo (OR 1.76, 95% CI 0.78 to 3.99; 1 study, 107 participants; low-certainty evidence); comparing sulphinpyrazone versus placebo (OR 0.43, 95% CI 0.03 to 5.98; 1 study, 16 participants; low-certainty evidence) and comparing GTN patch and placebo (OR 1.26, 95% CI 0.63 to 2.54; 1 study, 167 participants; moderate-certainty evidence). The single trial evaluating warfarin was terminated early because of major bleeding events in the warfarin group. Only two studies published data on the secondary outcome of related interventions (surgical or radiological); there was insufficient evidence to determine if there was a difference in related interventions between placebo and treatment groups. None of the included studies reported on the duration of hospital stay.  Most studies reported complications ranging from mortality to nausea. However, data on complications were limited and reporting varied between studies. AUTHORS' CONCLUSIONS: The meta-analyses of three studies for ticlopidine (an antiplatelet treatment), which all used the same dose of treatment but with a short follow-up of only one month, suggest ticlopidine may have a beneficial effect as an adjuvant treatment to increase the patency of AVFs and AVGs in the short term. There was insufficient evidence to determine if there was a difference in graft patency between placebo and other treatments such as aspirin, fish oil, clopidogrel, dipyridamole, dipyridamole plus aspirin, warfarin, sulphinpyrazone and GTN patch. The certainty of the evidence was low to moderate due to short follow-up periods, the small number of studies for each comparison, small sample sizes, heterogeneity between trials and risk of bias due to incomplete reporting. Therefore, it appears reasonable to suggest further prospective studies be undertaken to assess the use of these antiplatelet drugs in renal patients with an AVF or AVG.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Falência Renal Crônica/terapia , Inibidores da Agregação Plaquetária/uso terapêutico , Grau de Desobstrução Vascular/efeitos dos fármacos , Quimioterapia Adjuvante , Óleos de Peixe/uso terapêutico , Oclusão de Enxerto Vascular/prevenção & controle , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal/métodos , Ticlopidina/uso terapêutico , Dispositivos de Acesso Vascular
3.
Chemistry ; 25(66): 15155-15163, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31444824

RESUMO

Self-assembly of organic small molecules into an ordered thin film has been the key strategy towards efficient charge transport for organic field-effect transistors (OFETs). Solution processing is a feasible and economic way to enhance pi-pi interaction. Herein, nitrile-substituted unsymmetrical triarylamines for OFET applications with high mobility are reported. The compounds were constructed by Suzuki cross-coupling reactions under inert conditions. The HOMO level of about 5.3 eV indicates good hole-transporting ability. OFETs were assembled in bottom-gate, top-contact architecture. Devices fabricated from a binary solvent system exhibited excellent p-channel characteristics, with impressively high charge-carrier mobility of up to 2.58 cm2 V-1 s-1 and ION/OFF current ratios of 106 -107 . SEM and AFM analysis showed the efficient molecular self-assembly attained by the simple and effective solvent-engineering method. Theoretical insights obtained by DFT calculations supported by single-crystal structures showed that the crystalline nature and packing modes of these compounds ensure high mobility. The results prove that these compounds have great potential for use in numerous electronic applications, such as sensors and logic switches.

4.
Int J Colorectal Dis ; 34(4): 771, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30767044

RESUMO

The above article originally published with an error present in Table 1 and is now presented correctly in this article.

5.
Int J Colorectal Dis ; 34(3): 527-531, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30617413

RESUMO

BACKGROUND: Appendicitis can be secondary to caecal pathology (polyp or cancer). Increasing age is a risk factor for malignancy coexisting with appendicitis. There is an increased coexistence of cancer post-appendicectomy in patients aged 50-54 years. This study investigates whether post-appendicectomy patients aged over 40 years should receive further colorectal imaging and follow-up. METHODS: Retrospective data were collected for 1633 patients aged 40 years and over who underwent appendicectomy in a 10-year period (1st January 2004-31st December 2014). Data were analysed for patients with histological confirmation of acute appendicitis. Incidental appendicular tumours were excluded. RESULTS: One thousand fifty-five (64%) patients had histological confirmation of acute appendicitis (median age 52 years; range 40-96 years). Six hundred three patients (57%) were aged 40-54 years; 452 patients (43%) were aged 55 years or over. Twenty-six (2.5%) patients were investigated post-appendicectomy. Three (11.5%) had caecal pathology: 2 adenocarcinoma, 1 benign caecal polyp. Ten (2.2%) patients aged 55 years or over had caecal pathology. Seven (1.6%) were diagnosed with caecal cancer. No patients below age 54 years were diagnosed with caecal cancer. The incidence of caecal cancer in the study population was 0.66% (40-54.9 years 0%; 55 years and over 1.6%). Patients aged 55 years or over were more likely to develop caecal pathology than patients aged 40-54 years (p = 0.006). The odds ratio of developing caecal pathology was 6.8 times greater (95% CI 1.49-31.29) in people aged 55 years and over. CONCLUSIONS: Patients aged 55 years or over who have undergone appendicectomy should be offered colonoscopy to exclude coexistent caecal pathology.


Assuntos
Apendicectomia , Apendicite/complicações , Apendicite/cirurgia , Colo/diagnóstico por imagem , Neoplasias do Colo/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ceco/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Appl Opt ; 53(10): 2001-6, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24787153

RESUMO

Electromagnetic metamaterials, made from arrangements of subwavelength-sized structures, can be used to manipulate radiation. Designing metamaterials that have a positive refractive index along one axis and a negative refractive index along the orthogonal axis can result in birefringences, Δn>1. The effect can be used to create wave plates with subwavelength thicknesses. Previous attempts at making wave plates in this way have resulted in very narrow usable bandwidths. In this paper, we use the Pancharatnam method to increase the usable bandwidth. A combination of finite element method and transmission line models was used to optimize the final design. Experimental results are compared with the modeled data.

9.
Oral Maxillofac Surg ; 28(3): 1227-1239, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38565824

RESUMO

PURPOSE: The purpose of this study was to assess success rates and to report complications of coronectomy of mandibular third molars (M3M), including intra-operative failure, pain, infection, dry socket, inferior dental alveolar (IAN) and lingual nerve (LN) injuries and re-operation rates. METHODS: Retrospective analysis of 167 coronectomies completed between January 2017 to December 2022 was undertaken. RESULTS: The success of coronectomy was 93%. Intra-operative failure was reported to be 3.6% (n = 8). Complications accounted for pain (15%, n = 24), infection (9%, n = 15) and dry socket (3.6%, n = 6). Three patients required removal of M3M root at 3 months (n = 2) and 24 months (n = 1), accounting for 1.8% re-operation rate. A total of number of patients who suffered a nerve injury was 12; three of these were permanent (LN - 1.2%, n = 2; IAN - 0.6%, n = 1), nine were temporary (IAN - 1.2%; n = 2, LN - 2.4%; n = 4; site not specified - 1.8%, n = 3). No patients with intra-operative failure and re-operation suffered IAN or LN injury post-operatively. CONCLUSION: Coronectomy offers a successful strategy for management of high risk M3M. The treatment outcomes can be improved with careful case selection and adjusting surgical technique, including assessment of root morphology, incomplete crown sectioning technique and avoidance of lingual retraction. Reporting of coronectomy success as a factor of surgical outcome, presence or absence of permanent IAN injury, persistent symptoms or any other long-standing complications (such as LN injury), and the need for re-operation accounting for root migration status may be a useful tool to measure coronectomy outcomes.


Assuntos
Mandíbula , Dente Serotino , Complicações Pós-Operatórias , Coroa do Dente , Humanos , Dente Serotino/cirurgia , Estudos Retrospectivos , Masculino , Adulto , Feminino , Coroa do Dente/cirurgia , Mandíbula/cirurgia , Complicações Pós-Operatórias/etiologia , Pessoa de Meia-Idade , Extração Dentária , Reoperação , Adolescente , Resultado do Tratamento , Dente Impactado/cirurgia , Adulto Jovem , Complicações Intraoperatórias
10.
Chempluschem ; 89(8): e202400018, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38446710

RESUMO

Organic memory devices have attracted attention because they promise flexible electronics, low manufacturing costs, and compatibility with large-scale integration. A series of new D-A architectures were synthesized employing different donor groups and the isatin moiety as the acceptor through Suzuki-Miyaura coupling reactions. Strong intramolecular interactions were observed in the synthesized compounds, further corroborated by an optimal bandgap. The SEM investigation confirmed good molecular ordering and superior thin film surface coverage. All the compounds demonstrated notable binary Write-Once-Read-Many-Times (WORM) memory behaviour. The threshold switching voltage for these D-A systems ranged from -0.79 to -2.37 V, with the compound having isobutyl substituent showing the lowest threshold voltage and maximum ON/OFF ratio of 102, thus outperforming others. The combined effects of charge transfer and charge trapping are responsible for the resistive switching mechanism prevailing in these systems. The alterations in D-A molecules that affect molecular packing, thin film morphology, and, finally, the memory performance of the active layer are highlighted in this work.

12.
Sci Rep ; 13(1): 22324, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38102148

RESUMO

Management of vehicle traffic is a challenging task as it is non-deterministic by nature. Vehicular Cyber-Physical Systems (VCPS) is the emerging field of dynamics of vehicle management. Vehicle localization is considered an important task in VCPS. Many researchers proposed methodologies for this based on the Global Positioning System (GPS) which poses few location identification errors. Also, there are more vulnerabilities to the existing vehicular positioning system due to Zig-Zag attacks and bad-mouth attacks. In this work, an error-free and secure environment for communication between dynamically moving vehicle models has been proposed. In our proposed model a localization technique based on mathematical geometry which is capable of GPS outages and encompasses the dynamism of vehicle and on-road trajectory has been developed. The proposed model includes Extended Kalman filter-based routing to predict the neighbouring vehicle position. To avoid vulnerabilities created by the malicious nodes, a trust-based computation is performed by each node on its neighbours perceiving the authenticity of received messages. To validate the methodology, NS2 tool has been used to simulate the VCPS and to test the efficiency with different scenarios such as erroneous location, GPS outage, and malicious attack. The result shows that the proposed approach is more optimal and secure than the existing methodologies.

13.
Nanomaterials (Basel) ; 12(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36432314

RESUMO

6-Mercaptopurine (6-MP) is a well-known immunosuppressive medication with proven anti-proliferative activities. 6-MP possesses incomplete and highly variable oral absorption due to its poor water solubility, which might reduce its anti-cancer properties. To overcome these negative effects, we developed neutral and positively charged drug-loaded liposomal formulations utilizing the thin-film hydration technique. The prepared liposomal formulations were characterized for their size, polydispersity index (PDI), zeta potential, and entrapment efficiency. The average size of the prepared liposomes was between 574.67 ± 37.29 and 660.47 ± 44.32 nm. Positively charged liposomes (F1 and F3) exhibited a lower PDI than the corresponding neutrally charged ones (F2 and F4). Entrapment efficiency was higher in the neutral liposomes when compared to the charged formulation. F1 showed the lowest IC50 against HepG2, HCT116, and MCF-7 cancer cells. HepG2 cells treated with F1 showed the highest level of inhibition of cell proliferation with no evidence of apoptosis. Cell cycle analysis showed an increase in the G1/G0 and S phases, along with a decrease in the G2/M phases in the cell lines treated with drug loaded positively charged liposomes when compared to free positive liposomes, indicating arrest of cells in the S phase due to the stoppage of priming and DNA synthesis outside the mitotic phase. As a result, liposomes could be considered as an effective drug delivery system for treatment of a variety of cancers; they provide a chance that a nanoformulation of 6-MP will boost the cytotoxicity of the drug in a small pharmacological dose which provides a dosage advantage.

14.
J Perioper Pract ; 31(3): 62-70, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33544661

RESUMO

BACKGROUND: The UK practice of laparoscopic cholecystectomy has reduced during the COVID-19 pandemic due to cancellation of non-urgent operations. Isolated day-case units have been recommended as 'COVID-cold' operating sites to resume surgical procedures. This study aims to identify patients suitable for day case laparoscopic cholecystectomy (DCLC) at isolated units by investigating patient factors and unexpected admission. METHOD: Retrospective analysis of 327 patients undergoing DCLC between January and December 2018 at Ysbyty Gwynedd (District General Hospital; YG) and Llandudno General Hospital (isolated unit; LLGH), North Wales, UK. RESULTS: The results showed that 100% of DCLCs in LLGH were successful; 71.4% of elective DCLCs were successful at YG. Increasing age (p = 0.004), BMI (p = 0.01), ASA Score (p = 0.006), previous ERCP (p = 0.05), imaging suggesting cholecystitis (p = 0.003) and thick-walled gallbladder (p = 0.04) were significantly associated with failed DCLC on univariate analysis. Factors retaining significance (OR, 95% CI) after multiple regression include BMI (1.82, 1.05-3.16; p = 0.034), imaging suggesting cholecystitis (4.42, 1.72-11.38; p = 0.002) and previous ERCP (5.25, 1.53-18.00; p = 0.008). Postoperative complications are comparable in BMI <35kg/m2 and 35-39.9kg/m2. CONCLUSIONS: Current patient selection for isolated day unit is effective in ensuring safe discharge and could be further developed with greater consideration for patients with BMI 35-39.9kg/m2. As surgical services return, this helps identify patients suitable for laparoscopic cholecystectomy at isolated COVID-free day units.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/estatística & dados numéricos , COVID-19/epidemiologia , Colecistectomia Laparoscópica/estatística & dados numéricos , Adulto , Colecistite/cirurgia , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Feminino , Vesícula Biliar/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , País de Gales
16.
World J Gastrointest Oncol ; 11(12): 1182-1192, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31908723

RESUMO

BACKGROUND: Malnourishment and sarcopenia are well documented phenomena in oesophageal cancer. Patients undergoing neo-adjuvant chemotherapy prior to oesophagectomy have complex nutritional needs. AIM: To examine the effect of regular nutritional support via feeding jejunostomy on overall body composition in patients undergoing neo-adjuvant chemotherapy prior to oesophagectomy for oesophageal cancer. METHODS: Retrospective data were collected for 15 patients before and after neo-adjuvant chemotherapy. All patients had feeding jejunostomies inserted at staging laparoscopy prior to neo-adjuvant chemotherapy and underwent regular jejunostomy feeding. Changes in body composition were determined by analysis of computed tomography imaging. RESULTS: Patient age was 61.3 ± 12.8 years, and 73% of patients were male. The time between start of chemotherapy and surgery was 107 ± 21.6 d. There was no change in weight (74.5 ± 14.1 kg to 74.8 ± 13.1 kg) and body mass index (26.0 ± 3.8 kg/m2 to 26.1 ± 3.4 kg/m2). Body composition analysis revealed a statistically significant decrease in lumbar skeletal muscle index despite regular feeding (45.8 ± 8.0 cm2/m2 to 43.5 ± 7.3 cm2/m2; P = 0.045). The proportion of sarcopenic patients increased (33.3% to 60%). Six patients (40%) experienced dose-limiting toxicity during chemotherapy. CONCLUSION: Regular jejunostomy feeding during neo-adjuvant chemotherapy can maintain weight and adipose tissue. Feeding alone is not sufficient to maintain muscle mass. Further insight into the underlying processes causing reduced muscle mass in cancer patients may help to provide targeted interventions.

17.
18.
J Antibiot (Tokyo) ; 70(6): 754-762, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28377637

RESUMO

Extended-spectrum ß-lactamase (ESBL)-producing bacteria pose a big challenge in clinical practices, warranting a new therapeutic strategy. In this study, methanol extract of the marine cyanobacterium Oscillatoria acuminata NTAPC05 was fractionated under bioassay guidance and the fractions were tested against three well-characterized ESBL-producing bacteria Escherichia coli U655, Stenotrophomonas maltophilia B929 and Enterobacter asburiae B938. Out of the four HPLC fractions, fraction 2 showed bactericidal activity against all the three ESBL producers much more efficiently (MIC 100 µg ml-1) than the fourth-generation cephalosporin (MIC >125 µg ml-1). The active fraction was subjected to time-kill test at concentrations of 1/2 × MIC, 1 × MIC and 2 × MIC, and the results substantiated the bactericidal property of the fraction against the ESBL producers. Spectral analysis revealed monogalactosyldiacylglycerol containing a palmitoyl (MGDG-palmitoyl), being reported for the first time, as the active fraction, and its bactericidal property against ESBL producers was determined. The active fraction appears to damage the bacterial membrane leading to lysis of the cell, as revealed in confocal laser scanning microscopy (CLSM) analysis, that was confirmed in scanning electron microscopic analysis. Cytotoxicity assay revealed the O. acuminata compound to be safe to a normal cell line HEK293 (human embryonic kidney cell). The in silico analysis of MGDG-palmitoyl revealed two successive H-bonding interactions with Leu198 of TEM1 ß-lactamase. Taken together, the MGDG-palmitoyl from O. acuminata NTAPC05 offers potential to develop analogs as a therapeutic for bacteremia caused by ESBL producers.


Assuntos
Antibacterianos/isolamento & purificação , Enterobacter/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Oscillatoria/metabolismo , Stenotrophomonas maltophilia/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Simulação por Computador , Galactolipídeos/química , Células HEK293 , Humanos , Testes de Sensibilidade Microbiana , Microscopia Confocal , Microscopia Eletrônica de Varredura , beta-Lactamases/metabolismo
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