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1.
Environ Sci Pollut Res Int ; 30(57): 119772-119795, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37973777

RESUMO

The global population spike, rise in industrialization, and highway infrastructure development induce focus on sustainable development. The ever-increasing consumption of non-renewable crude oil and asphalt levies a heavy toll on economic welfare of future generations. This enormous demand of asphalt is due to its wide applicability in flexible pavements. Therefore, the construction industry is exploring the partial substitution of renewable materials in asphalt with a focus on economical, social, and environmental benefits. The current decade has seen a rampant rise of bio-asphalt as an alternative to asphalt. Hence, it is imperative to explore the performance of bio-asphalt for its sustainable applicability. This review comprehensively summarizes the performance of bio-asphalt obtained from various biomass sources. It deals with elemental composition of bio-oil, preparation procedure, rheological performance, mixture performance, and aging mechanism of bio-asphalt along with modification required to improve the performance. The environmental impacts and field application of the bio-asphalts are also discussed.


Assuntos
Indústria da Construção , Biomassa , Hidrocarbonetos
2.
J Clin Pharmacol ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803948

RESUMO

This study investigated the differences in the pharmacokinetics (PK) of dextromethorphan and desipramine in healthy African volunteers to understand the effect of allelic variants of the human cytochrome P450 2D6 (CYP2D6) enzyme, namely the diplotypes of CYP2D6*1/*2 (*1*1, *1*2, *2*2) and the genotypes of CYP2D6*17*17 and CYP2D6*29*29. Overall, 28 adults were included and split into 3 cohorts after genotype screening: CYP2D6*1/*2 (n = 12), CYP2D6*17*17 (n = 12), and CYP2D6*29*29 (n = 4). Each subject received a single oral dose of dextromethorphan 30 mg syrup on day 1 and desipramine 50 mg tablet on day 8. The PK parameters of area under the plasma concentration-time curve from time of dosing to time of last quantifiable concentration (AUClast ), and extrapolated to infinity (AUCinf ), and the maximum plasma concentration (Cmax ) were determined. For both dextromethorphan and desipramine, AUCinf and Cmax were higher in subjects of the CYP2D6*29*29 and CYP2D6*17*17 cohorts, as compared with subjects in the CYP2D6*1/*2 diplotype cohort and with normal metabolizers from the literature. All PK parameters, including AUCinf , Cmax , and the elimination half-life, followed a similar trend: CYP2D6*17*17 > CYP2D6*29*29 > CYP2D6*1/*2. The plasma and urinary drug/metabolite exposure ratios of both drugs were higher in subjects of the CYP2D6*17*17 and CYP2D6*29*29 cohorts, when compared with subjects in the CYP2D6*1/*2 diplotype cohort. All adverse events were mild, except in 1 subject with CYP2D6*17*17 who had moderately severe headache with desipramine. These results indicate that subjects with CYP2D6*17*17 and CYP2D6*29*29 genotypes were 5-10 times slower metabolizers than those with CYP2D6*1/*2 diplotypes. These findings suggest that dose optimization may be required when administering CYP2D6 substrate drugs in African patients. Larger studies can further validate these findings.

3.
Vascul Pharmacol ; 151: 107191, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37399882

RESUMO

Sympathomimetic amines, including ß-phenylethylamine (PEA), constrict animal blood vessels but their mechanism of action is not now thought to be through α-adrenoceptors and release of noradrenaline but via trace amine-associated receptors (TAARs). This information is not available for human blood vessels. Functional studies were therefore performed on human arteries and veins to establish whether they constrict to PEA and whether any constrictions are adrenoceptor-mediated. Isolated internal mammary artery or saphenous vein rings were set up in Kreb's-bicarbonate solution at 37 ± 0.5 °C gassed with O2:CO2 (95:5) under class 2 containment. Isometric contractions were measured and cumulative concentration-response curves for PEA or the α-adrenoceptor agonist, phenylephrine were established. PEA showed concentration-related contractions. The maximum was significantly greater in arteries (1.53 ± 0.31 g, n = 9) than veins (0.55 ± 0.18 g, n = 10), but not when plotted as % of KCl contractions. PEA showed slowly developing contractions plateauing at 17,3 ± 3.7 min in mammary artery. The reference α-adrenoceptor agonist, phenylephrine, exhibited more rapid onset (peak 5.0 ± 1.2 min) but non-sustained contractions. In saphenous veins, PEA (62.8 ± 10.7%) and phenylephrine (61.4 ± 9.7%, n = 4) displayed the same maximum, but phenylephrine was more potent. The α1-adrenoceptor antagonist, prazosin (1 µM), blocked phenylephrine contractions of mammary arteries but not PEA contractions in either vessel. PEA causes substantial vasoconstriction of human saphenous vein and mammary artery, which explains its vasopressor actions. This response, however, was not mediated via α1-adrenoceptors, but likely due to TAARs. The classification of PEA as a sympathomimetic amine on human blood vessels is therefore no longer valid and requires revision.


Assuntos
Artéria Torácica Interna , Animais , Humanos , Artéria Torácica Interna/fisiologia , Vasoconstrição , Veia Safena , Fenilefrina/farmacologia , Norepinefrina , Receptores Adrenérgicos
4.
Lancet Infect Dis ; 23(9): 1051-1061, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37327809

RESUMO

BACKGROUND: Emergence of drug resistance demands novel antimalarial drugs with new mechanisms of action. We aimed to identify effective and well tolerated doses of ganaplacide plus lumefantrine solid dispersion formulation (SDF) in patients with uncomplicated Plasmodium falciparum malaria. METHODS: This open-label, multicentre, parallel-group, randomised, controlled, phase 2 trial was conducted at 13 research clinics and general hospitals in ten African and Asian countries. Patients had microscopically-confirmed uncomplicated P falciparum malaria (>1000 and <150 000 parasites per µL). Part A identified the optimal dose regimens in adults and adolescents (aged ≥12 years) and in part B, the selected doses were assessed in children (≥2 years and <12 years). In part A, patients were randomly assigned to one of seven groups (once a day ganaplacide 400 mg plus lumefantrine-SDF 960 mg for 1, 2, or 3 days; ganaplacide 800 mg plus lumefantrine-SDF 960 mg as a single dose; once a day ganaplacide 200 mg plus lumefantrine-SDF 480 mg for 3 days; once a day ganaplacide 400 mg plus lumefantrine-SDF 480 mg for 3 days; or twice a day artemether plus lumefantrine for 3 days [control]), with stratification by country (2:2:2:2:2:2:1) using randomisation blocks of 13. In part B, patients were randomly assigned to one of four groups (once a day ganaplacide 400 mg plus lumefantrine-SDF 960 mg for 1, 2, or 3 days, or twice a day artemether plus lumefantrine for 3 days) with stratification by country and age (2 to <6 years and 6 to <12 years; 2:2:2:1) using randomisation blocks of seven. The primary efficacy endpoint was PCR-corrected adequate clinical and parasitological response at day 29, analysed in the per protocol set. The null hypothesis was that the response was 80% or lower, rejected when the lower limit of two-sided 95% CI was higher than 80%. This study is registered with EudraCT (2020-003284-25) and ClinicalTrials.gov (NCT03167242). FINDINGS: Between Aug 2, 2017, and May 17, 2021, 1220 patients were screened and of those, 12 were included in the run-in cohort, 337 in part A, and 175 in part B. In part A, 337 adult or adolescent patients were randomly assigned, 326 completed the study, and 305 were included in the per protocol set. The lower limit of the 95% CI for PCR-corrected adequate clinical and parasitological response on day 29 was more than 80% for all treatment regimens in part A (46 of 50 patients [92%, 95% CI 81-98] with 1 day, 47 of 48 [98%, 89-100] with 2 days, and 42 of 43 [98%, 88-100] with 3 days of ganaplacide 400 mg plus lumefantrine-SDF 960 mg; 45 of 48 [94%, 83-99] with ganaplacide 800 mg plus lumefantrine-SDF 960 mg for 1 day; 47 of 47 [100%, 93-100] with ganaplacide 200 mg plus lumefantrine-SDF 480 mg for 3 days; 44 of 44 [100%, 92-100] with ganaplacide 400 mg plus lumefantrine-SDF 480 mg for 3 days; and 25 of 25 [100%, 86-100] with artemether plus lumefantrine). In part B, 351 children were screened, 175 randomly assigned (ganaplacide 400 mg plus lumefantrine-SDF 960 mg once a day for 1, 2, or 3 days), and 171 completed the study. Only the 3-day regimen met the prespecified primary endpoint in paediatric patients (38 of 40 patients [95%, 95% CI 83-99] vs 21 of 22 [96%, 77-100] with artemether plus lumefantrine). The most common adverse events were headache (in seven [14%] of 51 to 15 [28%] of 54 in the ganaplacide plus lumefantrine-SDF groups and five [19%] of 27 in the artemether plus lumefantrine group) in part A, and malaria (in 12 [27%] of 45 to 23 [44%] of 52 in the ganaplacide plus lumefantrine-SDF groups and 12 [50%] of 24 in the artemether plus lumefantrine group) in part B. No patients died during the study. INTERPRETATION: Ganaplacide plus lumefantrine-SDF was effective and well tolerated in patients, especially adults and adolescents, with uncomplicated P falciparum malaria. Ganaplacide 400 mg plus lumefantrine-SDF 960 mg once daily for 3 days was identified as the optimal treatment regimen for adults, adolescents, and children. This combination is being evaluated further in a phase 2 trial (NCT04546633). FUNDING: Novartis and Medicines for Malaria Venture.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária , Adulto , Adolescente , Criança , Humanos , Lumefantrina/farmacologia , Lumefantrina/uso terapêutico , Fluorenos/uso terapêutico , Fluorenos/farmacologia , Etanolaminas/uso terapêutico , Etanolaminas/farmacologia , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Artemeter/farmacologia , Artemeter/uso terapêutico , Malária/tratamento farmacológico , Combinação de Medicamentos , Plasmodium falciparum , Resultado do Tratamento
5.
BMJ Open ; 11(10): e046491, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711589

RESUMO

OBJECTIVES: To date the reported outcomes of surgical aortic valve replacement (SAVR) are mainly in the settings of trials comparing it with evolving transcatheter aortic valve implantation. We set out to examine characteristics and outcomes in people who underwent SAVR reflecting a national cohort and therefore 'real-world' practice. DESIGN: Retrospective analysis of prospectively collected data of consecutive people who underwent SAVR with or without coronary artery bypass graft (CABG) surgery between April 2013 and March 2018 in the UK. This included elective, urgent and emergency operations. Participants' demographics, preoperative risk factors, operative data, in-hospital mortality, postoperative complications and effect of the addition of CABG to SAVR were analysed. SETTING: 27 (90%) tertiary cardiac surgical centres in the UK submitted their data for analysis. PARTICIPANTS: 31 277 people with AVR were identified. 19 670 (62.9%) had only SAVR and 11 607 (37.1%) had AVR+CABG. RESULTS: In-hospital mortality for isolated SAVR was 1.9% (95% CI 1.6% to 2.1%) and was 2.4% for AVR+CABG. Mortality by age category for SAVR only were: <60 years=2.0%, 60-75 years=1.5%, >75 years=2.2%. For SAVR+CABG these were; 2.2%, 1.8% and 3.1%. For different categories of EuroSCORE, mortality for SAVR in low risk people was 1.3%, in intermediate risk 1% and for high risk 3.9%. 74.3% of the operations were elective, 24% urgent and 1.7% emergency/salvage. The incidences of resternotomy for bleeding and stroke were 3.9% and 1.1%, respectively. Multivariable analyses provided no evidence that concomitant CABG influenced outcome. However, urgency of the operation, poor ventricular function, higher EuroSCORE and longer cross clamp and cardiopulmonary bypass times adversely affected outcomes. CONCLUSIONS: Surgical SAVR±CABG has low mortality risk and a low level of complications in the UK in people of all ages and risk factors. These results should inform consideration of treatment options in people with aortic valve disease.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Reino Unido/epidemiologia
6.
J Surg Case Rep ; 2020(5): rjaa066, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32509262

RESUMO

Median sternotomy has been used to aide thyroidectomies demonstrating good outcomes; however no cases have been documented to show the use of mini-sternotomy to perform simultaneous thyroidectomy and valve surgery. We present a novel case of an 83-year-old woman with severe aortic stenosis and retrosternal goitre extending to the aortic arch deemed unsuitable for TAVI. Due to co-morbid status and anatomical position preventing routine thyroidectomy, we elected to perform a combined procedure to excise the goitre and perform an aortic valve replacement through a mini-J sternotomy, utilizing 3D-reconstructed imaging to plan our approach. This case shows that mini-sternotomy is a safe and effective method to perform concomitant thyroidectomy and aortic valve surgery.

7.
Ann Med Surg (Lond) ; 43: 5-12, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31193454

RESUMO

BACKGROUND: Emergency Cardiac Surgery (ECS) is a component of cardiothoracic training. Citations are considered to represent a papers influence. Bibliometric analyses allow us to identify the most influential work, and future research. We aim to highlight the key research themes within ECS and determine their potential impact on cardiothoracic training. METHODS: Thomas Reuters Web of Science was searched using terms [Emergency AND Card* AND Surg*]. Results were ranked by citation and reviewed by a panel of cardiac surgeons to identify the top 100 cited papers relevant to ECS. Papers were analysed by topic, journal and impact. Regression analysis was used to determine a link between impact factor and scientific impact. RESULTS: 3823 papers were identified. Median citations for the top 100 was 88. The paper with the highest impact was by Nashef et al. focusing on the use of EuroSCORE (2043 citations). The Annals of Thoracic Surgery published most papers (n = 18:1778 citations). The European Journal of Cardiothoracic Surgery coveted the most citations (n = 2649). The USA published most papers (n = 55).The most ubiquitous topics were; risk stratification, circulatory support and aortic surgery. A positive relationship between journal impact fact and the scientific impact of manuscripts in ECS (P = 0.043) was deduced. CONCLUSION: This study is the first of its kind and identified the papers which are likely to the contribute most to training and understanding of ECS. A papers influence is partially determined by journal impact factor. Bibliometric analysis is a potent tool to identify surgical training needs.

8.
Arab J Urol ; 16(4): 378-385, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30534435

RESUMO

OBJECTIVE: To report our long-term outcomes of surgical treatment of renal tumours with inferior vena cava (IVC) tumour thrombus above the hepatic veins, utilising cardiopulmonary bypass (CBP) and hypothermic circulatory arrest (HCA), as surgical resection remains the only effective treatment for renal cancers with extensive IVC tumour thrombus. PATIENTS AND METHODS: We retrospectively reviewed 48 consecutive patients (median age 58 years) who underwent surgical treatment for non-metastatic renal cancer with IVC tumour thrombus extending above the hepatic veins. Perioperative, histological, disease-free (DFS) and overall survival (OS) data were recorded. RESULTS: Tumour thrombus was level III in 23 patients and level IV in 25 patients. The median (range) CBP and HCA times were 162 (120-300) min and 35 (9-64) min, respectively. Three patients underwent synchronous cardiac surgical procedures. There were three (6.3%) perioperative deaths. American Society of Anesthesiologists grade and perioperative blood transfusion requirement were significant factors associated with perioperative death (P < 0.05). Despite extensive preoperative screening for metastases the median (range) DFS was only 10.2 (1.2-224.4) months. The median (range) OS was 23 (0-224.4) months. Cox regression analysis revealed that perinephric fat invasion conferred a significantly poorer DFS (P = 0.005). CONCLUSIONS: Radical surgery for patients with extensive IVC tumour thrombus has acceptable operative morbidity and mortality. It provides symptom palliation and the possibility of long-term survival. Improvements in preoperative detection of occult metastasis may improve case selection and newer adjuvant therapies may improve survival in this high-risk group.

9.
Ann Thorac Surg ; 102(6): e525-e527, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27847072

RESUMO

A patient with anomalous coronary circulation presented with non-ST segment elevation myocardial infarction and ischemic mitral regurgitation and underwent mitral valve repair and coronary revascularization. An unexpected tear occurred in the roof of the left atrium, and its subsequent repair caused iatrogenic damage of the anomalous circumflex artery on its abnormal course requiring an extra graft. Early suspicion of the iatrogenic damage to the anomalous artery was the key for good and complete recovery in this case.


Assuntos
Anomalias dos Vasos Coronários/complicações , Implante de Prótese de Valva Cardíaca/efeitos adversos , Doença Iatrogênica , Insuficiência da Valva Mitral/cirurgia , Infarto do Miocárdio/cirurgia , Idoso , Anomalias dos Vasos Coronários/diagnóstico por imagem , Humanos , Masculino , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/etiologia , Infarto do Miocárdio/complicações
10.
Blood Coagul Fibrinolysis ; 26(4): 357-67, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25928274

RESUMO

Recently, lower thrombin generation has been associated with excess bleeding post-cardiopulmonary bypass (CPB). Therefore, treatment to correct thrombin generation is a potentially important aspect of management of bleeding in this group of patients. The objective of the present study was to investigate the effects of fresh frozen plasma (FFP), recombinant factor VIIa (rFVIIa), prothrombin complex concentrate (PCC) and tissue factor pathway inhibitor (TFPI) inhibition on thrombin generation when added ex vivo to the plasma of patients who had undergone cardiac surgery requiring CPB. Patients undergoing elective cardiac surgery were recruited. Blood samples were collected before administration of heparin and 30 min after its reversal. Thrombin generation was measured in the presence and absence of different concentrations of FFP, rFVIIa, PCC and an anti-TFPI antibody. A total of 102 patients were recruited. Thrombin generation following CPB was lower compared with pre-CPB (median endogenous thrombin potential pre-CPB 339 nmol/l per min, post-CPB 155 nmol/l per min, P < 0.0001; median peak thrombin pre-CPB 35 nmol/l, post-CPB 11 nmol/l, P < 0.0001). Coagulation factors and anticoagulants decreased, apart from total TFPI, which increased (55-111 ng/ml, P < 0.0001), and VWF (144-170 IU/dl, P < 0.0001). Thrombin generation was corrected to pre-CPB levels by the equivalent of 15 ml/kg FFP, 45 µg/kg rFVIIa and 25 U/kg of PCC. Inhibition of TFPI resulted in an enhancement of thrombin generation significantly beyond pre-CPB levels. This study shows that FFP, rFVIIa, PCC and inhibition of TFPI correct thrombin generation in the plasma of patients who have undergone surgery requiring CPB. Inhibition of TFPI may be a further potential therapeutic strategy for managing bleeding in this group of patients.


Assuntos
Fatores de Coagulação Sanguínea/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Ponte Cardiopulmonar , Fator VIIa/farmacologia , Hemostáticos/farmacologia , Trombina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/farmacologia , Testes de Coagulação Sanguínea , Procedimentos Cirúrgicos Cardíacos , Feminino , Humanos , Lipoproteínas/farmacologia , Masculino , Pessoa de Meia-Idade , Plasma/metabolismo , Proteínas Recombinantes/farmacologia
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