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1.
J Lipid Res ; 65(1): 100484, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103786

RESUMO

Aminophospholipids (aPL) such as phosphatidylserine are essential for supporting the activity of coagulation factors, circulating platelets, and blood cells. Phosphatidylthreonine (PT) is an aminophospholipid previously reported in eukaryotic parasites and animal cell cultures, but not yet in human tissues. Here, we evaluated whether PT is present in blood cells and characterized its ability to support coagulation. Several PT molecular species were detected in human blood, washed platelets, extracellular vesicles, and isolated leukocytes from healthy volunteers using liquid chromatography-tandem mass spectrometry. The ability of PT to support coagulation was demonstrated in vitro using biochemical and biophysical assays. In liposomes, PT supported prothrombinase activity in the presence and absence of phosphatidylserine. PT nanodiscs strongly bound FVa and lactadherin (nM affinity) but poorly bound prothrombin and FX, suggesting that PT supports prothrombinase through recruitment of FVa. PT liposomes bearing tissue factor poorly generated thrombin in platelet poor plasma, indicating that PT poorly supports extrinsic tenase activity. On platelet activation, PT is externalized and partially metabolized. Last, PT was significantly higher in platelets and extracellular vesicle from patients with coronary artery disease than in healthy controls. In summary, PT is present in human blood, binds FVa and lactadherin, supports coagulation in vitro through FVa binding, and is elevated in atherosclerotic vascular disease. Our studies reveal a new phospholipid subclass, that contributes to the procoagulant membrane, and may support thrombosis in patients at elevated risk.


Assuntos
Doença da Artéria Coronariana , Glicerofosfolipídeos , Treonina/análogos & derivados , Tromboplastina , Animais , Humanos , Tromboplastina/metabolismo , Fosfatidilserinas/metabolismo , Lipossomos/metabolismo , Plaquetas/metabolismo , Trombina/metabolismo
2.
Catheter Cardiovasc Interv ; 100(4): 585-592, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36104863

RESUMO

INTRODUCTION: Left main stem percutaneous coronary intervention (LMS-PCI) is a complex high-risk procedure which can be performed as an alternative to coronary artery bypass graft (CABG) procedure in surgical turn-down patients or where there is equipoise in percutaneous versus surgical strategies. Current guidelines suggest that PCI is an appropriate alternative to CABG in patients with unprotected LMS disease and low SYNTAX score. However, "real world" data on outcomes of LMS-PCI remain limited. This study aims to quantify and determine predictors of mortality following LMS-PCI. METHODS: Using local coronary angioplasty registries from two UK centers, all LMS-PCI cases were identified from 2016 to 2020. Descriptive statistics and multivariate logistic regressions were used to examine the association between baseline and procedural characteristics with 30-day and 12-month mortality. RESULTS: We identified 484 cases of LMS-PCI between 2016 and 2020. There was a year-on-year increase in the number of LMS-PCI, the highest being in 2020. Covariates associated with higher 30-day mortality were age (OR 1.07, 95% CI: 1.02-1.12) and shock preprocedure (OR 23.88, 95% CI: 7.90-72.20). Covariates associated with higher 12-month mortality were age (OR 1.04, 95% CI: 1.01-1.08), acute coronary syndrome (ACS) (OR 2.50, 95% CI: 1.08-5.80), renal disease (OR 5.24, 95% CI: 1.47-18.68), and shock preprocedure (OR 7.93, 95% CI: 3.30-19.05). Overall, 30-day and 12-month mortality in this contemporary data set were 9.5% and 16.7%, respectively, with significantly lower rates in elective cases (p < 0.01). CONCLUSIONS: Older age and cardiogenic shock preprocedure were associated with increased 30-day mortality after LMS-PCI. Twelve-month mortality was associated with older age, ACS presentation, preexisting renal disease, and cardiogenic shock preprocedure.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Fatores de Risco , Choque Cardiogênico , Resultado do Tratamento , Reino Unido/epidemiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-36525378

RESUMO

OBJECTIVES: To explore the long-term clinical outcomes following intravascular lithotripsy (IVL) in calcified coronary lesions from a real-world population. BACKGROUND: IVL is a relatively new but promising modality for treating coronary calcified lesions, but there is a dearth of long-term outcome data from real-world patients. METHODS: This was a multicenter, observational study in which we enrolled all patients treated with IVL from November 2018 to February 2021 from eight centers in Europe and the United Kingdom. Procedural success, complications, and clinical outcomes (cardiac death, target vessel myocardial infarction [TVMI], target lesion revascularization [TLR], and MACE [major adverse cardiac events, the composite of cardiac death, TVMI, and TLR]) were assessed. RESULTS: In total, 273 patients with a mean age of 72 ± 9.1 years were treated with IVL. Major comorbidities included diabetes mellitus (n = 110, 40%) and chronic kidney disease (n = 45, 16%). Acute coronary syndrome accounted for 48% (n = 132) of patients, while 52% (n = 141) had stable angina. De novo lesions and in-stent restenosis accounted for 79% and 21% of cases, respectively. Intravascular imaging was used in 33% (n = 90) of patients. An upfront IVL strategy was adopted in 34% (n = 92), while the rest were bailout procedures. Adjuvant rotational atherectomy ("RotaTripsy") was required in 11% (n = 31) of cases. The procedural success was 99%. During a median follow-up of 687 days (interquartile range: 549-787), cardiac death occurred in 5% (n = 14), TVMI in 3% (n = 8), TLR in 6% (n = 16), and MACE rate was 11% (n = 30). CONCLUSION: This is the largest multicenter registry with a long-term follow-up showing the remarkably high procedural success of IVL use in calcified coronary lesions with low rates of hard endpoints and MACE.

4.
Arch Microbiol ; 204(7): 399, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35713724

RESUMO

Marine microbes produce polysaccharides with unique physicochemical and functional properties that help them survive in harsh marine environments. However, only a handful of marine exopolysaccharides (EPSs) have been reported to date. The present study explored the seashore of Visakhapatnam, India, to report a novel exopolysaccharide designated as Br42 produced by Brevibacillus borstelensis M42. The isolate was identified through morphological, biochemical, phylogenetic, and genome sequencing analysis. The studies on fermentation kinetics revealed that EPS Br42 was a primary metabolite with a maximum production of 1.88 ± 0.02 g/L after 60 h when production broth was fortified with 2% glucose. Additionally, EPS Br42 was found to be a heteropolysaccharide consisting of glucose and galacturonic acid with a molecular weight of about 286 kDa. Interestingly, this molecule possesses industrially relevant functional properties such as water-holding (510 ± 0.35%), oil-holding (374 ± 0.12% for coconut oil and 384 ± 0.35% for olive oil), and swelling capacities (146.6 ± 5.75%). EPS Br42 could form an emulsion that was stable at a wide pH range for about 72 h and, in fact, performed better as compared to Span 20, a commercially used synthetic emulsifier. Moreover, this EPS was also found to be heat stable and exhibited non-Newtonian pseudoplastic behavior. These physicochemical and functional properties of polysaccharides suggest that the EPS Br42 has potential for multifarious industrial applications as an emulsifier, stabilizer, viscosifier, and binding agent.


Assuntos
Brevibacillus , Polissacarídeos Bacterianos , Brevibacillus/genética , Brevibacillus/metabolismo , Glucose/metabolismo , Filogenia
5.
Catheter Cardiovasc Interv ; 98(2): 225-235, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32936532

RESUMO

BACKGROUND: The recently introduced intravascular lithotripsy (IVL) appears promising and relatively safer than conventional approaches when dealing with calcified lesions. Although there are published reports on this novel technology, data from the real world are limited. In this study, we aim to report on the experience of IVL from a real-world population derived from six European centers that undertake high-volume complex coronary interventions. METHODS AND RESULTS: We enrolled all patients treated with IVL between November 2018 and February 2020 at six centers. Procedural success and complications were assessed along with clinical outcomes, which included: cardiac death, target vessel myocardial infarction (TVMI), target lesion revascularisation (TLR), and major adverse cardiac event (MACE) (composite of cardiac death, TVMI, and TLR). Hundred and ninety patients (200 lesions) with a mean age of 72 years were treated using IVL. Diabetes and chronic kidney disease were present in 50% (n = 95) and 16% (n = 30) of cases, respectively. Acute-coronary syndromes accounted for 91 (48%) of the cases. Most were de-novo lesions (77%; n = 154). Upfront use of IVL occurred in 26% of cases, while the rest were bail-out procedures due to inadequate predilatation with conventional balloons. Adjuvant rotational atherectomy was needed in 17% of cases. Procedural success was achieved in 99% of cases with a complication rate of 3%. During the median follow-up of 222 days, there was two cardiac deaths (1%), one case of TVMI (0.5%), 3 TLR (1.5%) taking the MACE rate to 2.6%. CONCLUSION: Use of IVL appears to be safe and effective in dealing with calcified-coronary lesions. A high success rate was observed with low procedural complications and event rates.


Assuntos
Aterectomia Coronária , Doença da Artéria Coronariana , Litotripsia , Calcificação Vascular , Idoso , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Humanos , Litotripsia/efeitos adversos , Stents , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/terapia
6.
Lancet ; 393(10175): 987-997, 2019 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-30827782

RESUMO

BACKGROUND: Supraflex is a sirolimus-eluting stent with a biodegradable polymer coating and ultra-thin struts. We aimed to compare Supraflex with the standard of care, Xience, an everolimus-eluting stent with a durable polymer coating, regarding clinical outcomes with a randomised trial in an all-comer population. METHODS: We did a prospective, randomised, single-blind, multicentre study (TALENT) across 23 centres in Europe (the Netherlands, Poland, the UK, Spain, Bulgaria, Hungary, and Italy). Eligible participants were aged 18 years or older, had one or more coronary artery stenosis of 50% or greater in a native coronary artery, saphenous venous graft, or arterial bypass conduit, and had a reference vessel diameter of 2·25-4·50 mm. Patients underwent percutaneous coronary intervention in an all-comer manner. We randomly assigned patients (1:1) to implantation of either a sirolimus-eluting stent with a biodegradable polymer coating and ultra-thin struts (Supraflex) or an everolimus-eluting stent with a durable polymer coating (Xience). Randomisation was done by local investigators by use of a web-based software with random blocks according to centre. The primary endpoint was a non-inferiority comparison of a device-oriented composite endpoint-cardiac death, target-vessel myocardial infarction, or clinically indicated target lesion revascularisation-between groups at 12 months after the procedure, assessed in an intention-to-treat population. On assumption of 1-year composite endpoint prevalence of 8·3%, a margin of 4·0% was defined for non-inferiority of the Supraflex group compared with the Xience group. This trial is registered with ClinicalTrials.gov, number NCT02870140. FINDINGS: Between Oct 21, 2016, and July 3, 2017, 1435 patients with 1046 lesions were randomly assigned to Supraflex, of whom 720 received the index procedure, and 715 patients with 1030 lesions were assigned to Xience, all receiving the index procedure. At 12 months, the primary endpoint had occurred in 35 patients (4·9 %) in the Supraflex group and in 37 patients (5·3%) in the Xience group (absolute difference -0·3% [one-sided 95% upper confidence bound 1·6%], pnon-inferiority<0·0001). Definite or probable stent thrombosis prevalence, a safety indicator, was low in both groups and did not differ between them. INTERPRETATION: The Supraflex stent was non-inferior to the Xience stent for a device-oriented composite clinical endpoint at 12 months in an all-comer population. Supraflex seems a safe and effective alternative drug-eluting stent to other stents in clinical practice. FUNDING: European Cardiovascular Research Institute.


Assuntos
Aterosclerose/terapia , Stents Farmacológicos , Everolimo/administração & dosagem , Imunossupressores/administração & dosagem , Intervenção Coronária Percutânea/instrumentação , Sirolimo/administração & dosagem , Idoso , Stents Farmacológicos/efeitos adversos , Determinação de Ponto Final , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Método Simples-Cego , Trombose/etiologia
7.
Am Heart J ; 198: 46-54, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29653648

RESUMO

AIMS: Access site choice for cases requiring rotational atherectomy (PCI-ROTA) is poorly defined. Using the British Cardiovascular Intervention Society PCI database, temporal changes and contemporary associates/outcomes of access site choice for PCI-ROTA were studied. METHODS AND RESULTS: Data were analysed from 11,444 PCI-ROTA procedures performed in England and Wales between 2007 and 2014. Multivariate logistic regression was used to identify predictors of access site choice and its association with outcomes. RESULTS: For PCI-ROTA, radial access increased from 19.6% in 2007 to 58.6% in 2014. Adoption of radial access was slower in females, those with prior CABG, and in patients with chronic occlusive (CTO) or left main disease. In 2013/14, the strongest predictors of femoral artery use were age (OR 1.02, [1.005-1.036], P = .008), CTO intervention (OR 1.95, [1.209-3.314], P = .006), and history of previous CABG (OR 1.68, [1.124-2.515], P = .010). Radial access was associated with reductions in overall length of stay, and increased rates of same-day discharge. Procedural success rates were similar although femoral access use was associated with increased access site complications (2.4 vs. 0.1%, P < .001). After adjustment for baseline differences, arterial complications (OR 15.6, P < .001), transfusion (OR 12.5, P = .023) and major bleeding OR 6.0, P < .001) remained more common with FA use. Adjusted mortality and MACE rates were similar in both groups. CONCLUSIONS: In contemporary practice, radial access for PCI-ROTA results in similar procedural success when compared to femoral access but is associated with shorter length of stay, and lower rates of vascular complication, major bleeding and transfusion.


Assuntos
Aterectomia Coronária/métodos , Cateterismo Cardíaco/métodos , Estenose Coronária/cirurgia , Intervenção Coronária Percutânea/métodos , Artéria Radial , Idoso , Aterectomia Coronária/mortalidade , Estudos de Coortes , Angiografia Coronária/métodos , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/mortalidade , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Intervenção Coronária Percutânea/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Sociedades Médicas , Estatísticas não Paramétricas , Análise de Sobrevida , Resultado do Tratamento , Reino Unido
8.
Catheter Cardiovasc Interv ; 92(7): 1220-1228, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30244504

RESUMO

INTRODUCTION: Prolonged dual anti-platelet therapy (DAPT) is undesirable in certain patients. The biolimus-A9 drug-coated stent (BA9-DCS) has a rapid drug-elution profile allowing shortened DAPT. METHODS: The demographics, procedural data, and clinical outcomes for 505 patients presenting with an ACS to three UK centres and treated with a BA9-DCS stent (PCI-DCS) were collected, and compared to a consecutive ACS cohort of unselected patients treated in the same period with drug-eluting stents (PCI-DES). RESULTS: PCI-DCS patients were older, more often female with hypertension, chronic kidney disease, severe LV dysfunction, and peripheral vascular disease more frequent than the PCI-DES cohort. PCI-DCS patients had a much higher Mehran bleed risk score (21.5 ± 7.7 vs. 15.9 ± 7.7, P < 0.0001). Baseline disease burden was greater in the PCI-DCS cohort with more left main and three vessel disease. During PCI, more stents (1.91 ± 1.1 vs. 1.57 ± 0.94, P < 0.0001), total stent length (38.2 ± 20.8 vs. 31.4 ± 20.3, P < 0.0001) and longer stents (38.2 ± 20.8 vs. 31.4 ± 20.3 mm, P < 0.0001) were used in the PCI-DCS cohort with rotational atherectomy also used more frequently. Physician-recommended DAPT duration was 2.9 ± 3.9 months for PCI-DCS patients and 11.3 ± 2.4 months for PCI-DES patients (P < 0.0001). At 12-month follow-up, definite stent thrombosis (0.6% vs. 1.1%) and TLR (3.2% vs. 2.7%) rates were similar between the two groups. After adjustment for baseline differences, there were no statistically significant differences in death and combined MACE rates at 12 months. CONCLUSIONS: The outcomes of patients treated with polymer-free BA9 drug-coated stent who present with an ACS and who were deemed unsuitable for prolonged DAPT are encouraging. Further studies are warranted.


Assuntos
Síndrome Coronariana Aguda/terapia , Fármacos Cardiovasculares/administração & dosagem , Doença da Artéria Coronariana/terapia , Stents Farmacológicos , Intervenção Coronária Percutânea/instrumentação , Inibidores da Agregação Plaquetária/administração & dosagem , Sirolimo/análogos & derivados , Síndrome Coronariana Aguda/mortalidade , Idoso , Idoso de 80 Anos ou mais , Fármacos Cardiovasculares/efeitos adversos , Doença da Artéria Coronariana/mortalidade , Esquema de Medicação , Quimioterapia Combinada , Feminino , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Inibidores da Agregação Plaquetária/efeitos adversos , Dados Preliminares , Desenho de Prótese , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Reino Unido
9.
Catheter Cardiovasc Interv ; 90(2): 186-193, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28266098

RESUMO

OBJECTIVES: The aim of this study was to examine the clinical and procedural outcomes of patients undergoing percutaneous coronary intervention (PCI) within 1 year of coronary artery bypass graft surgery (CABG). BACKGROUND: CABG is the preferred revascularization strategy for patients with complex coronary artery disease due to a lower rate of repeat revascularization. Despite advances in surgical technique and medical therapy, >5% of patients require repeat revascularization within 1 year of CABG. METHODS AND RESULTS: Patients who underwent PCI within 1 year of CABG were identified from a prospective registry with data on over 20,000 PCI procedures (April 2000-June 2011). 203 post-CABG patients underwent 228 PCI procedures on 390 lesions during this period. 45% of patients had elective PCI while 55% had PCI on an urgent basis. 81% of PCI was performed in native coronary arteries, usually following graft failure in a previously grafted vessel (60%) or in an ungrafted native vessel (21%). CONCLUSIONS: Patients who required PCI within 1 year of CABG were more likely to present on an urgent basis and have PCI performed in grafted native coronary vessels. However, nearly third of the patients had PCI to an ungrafted native vessel or to a lesion in the native vessel where the graft was still patent. Further studies are needed to determine whether the use of hybrid revascularization strategies (combination CABG and planned PCI) in appropriate patients could reduce the need for urgent PCI within the first year after CABG. © 2017 Wiley Periodicals, Inc.


Assuntos
Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Estenose Coronária/cirurgia , Oclusão de Enxerto Vascular/terapia , Intervenção Coronária Percutânea , Idoso , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/mortalidade , Stents Farmacológicos , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Ontário , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Intervenção Coronária Percutânea/mortalidade , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
10.
J Interv Cardiol ; 29(2): 129-36, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26822753

RESUMO

BACKGROUND: Prolonging infusions may abrogate the acute stent thrombosis (ST) associated with bivalirudin use during primary PCI but at an increased cost. We hypothesized that continuing the bivalirudin infusion commenced during the procedure at the PCI recommended dose until infusion end would prevent excess early ST. METHODS: Baseline demographics, procedural data and outcomes were gathered prospectively on 1395 consecutive patients undergoing primary PCI. The choice of bivalirudin versus heparin was at the cardiologist's discretion. Local protocol recommended continuation of the procedural bivalirudin at the PCI dose until infusion end. RESULTS: Patients' mean age was 62.8 ± 13.1years with 11.4% presenting with shock. The majority of patients underwent PCI using bivalirudin with fewer using heparin (87.7 vs. 12.3%, P < 0.0001). Glycoprotein inhibitor bailout rates were 6.1% with bivalirudin and 36.3% with heparin (P < 0.0001). Calculated on an individual patient basis the median intra-procedure duration of the bivalirudin infusion was 30(IQR 21-43) minutes and post-procedure 49(32-66) minutes. The acute (<24-hours) ST rates were 4/1224 with bivalirudin ± GPI (0.3%) and 0/171 with heparin ± GPI (0%, P = 0.41). The sub-acute (24-hours to 30-days) ST rates were 3/1224 for bivalirudin ± GPI (0.3%) and 2/171 with heparin ± GPI (1.2%, P = 0.11). In total the early (<30-days) ST rates were 7/1224 for bivalirudin ± GPI (0.6%) and 2/171 with heparin ± GPI (1.2%, P = 0.31). Acute ST was significantly more likely to occur in clopidogrel-loaded patients than prasugrel/ticagrelor patients (2.7 vs. 0.5%, P = 0.003). CONCLUSION: Continuing the bivalirudin infusion commenced during the procedure at the PCI recommended dose until infusion end combined with potent P2 Y12 inhibitors ameliorates excess early stent thrombosis.


Assuntos
Antitrombinas/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Intervenção Coronária Percutânea/efeitos adversos , Stents/efeitos adversos , Trombose/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Feminino , Heparina/uso terapêutico , Hirudinas , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/métodos , Intervenção Coronária Percutânea/mortalidade , Proteínas Recombinantes/uso terapêutico , Taxa de Sobrevida , Trombose/etiologia
11.
Microb Cell Fact ; 15: 25, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26829922

RESUMO

BACKGROUND: With the increased number of cholera outbreaks and emergence of multidrug resistance in Vibrio cholerae strains it has become necessary for the scientific community to devise and develop novel therapeutic approaches against cholera. Recent studies have indicated plausibility of therapeutic application of metal nano-materials. Among these, silver nanoparticles (AgNPs) have emerged as a potential antimicrobial agent to combat infectious diseases. At present nanoparticles are mostly produced using physical or chemical techniques which are toxic and hazardous. Thus exploitation of microbial systems could be a green eco-friendly approach for the synthesis of nanoparticles having similar or even better antimicrobial activity and biocompatibility. Hence, it would be worth to explore the possibility of utilization of microbial silver nanoparticles and their conjugates as potential novel therapeutic agent against infectious diseases like cholera. RESULTS: The present study attempted utilization of Ochrobactrum rhizosphaerae for the production of AgNPs and focused on investigating their role as antimicrobial agents against cholera. Later the exopolymer, purified from the culture supernatant, was used for the synthesis of spherical shaped AgNPs of around 10 nm size. Further the exopolymer was characterized as glycolipoprotein (GLP). Antibacterial activity of the novel GLP-AgNPs conjugate was evaluated by minimum inhibitory concentration, XTT reduction assay, scanning electron microscopy (SEM) and growth curve analysis. SEM studies revealed that AgNPs treatment resulted in intracellular contents leakage and cell lysis. CONCLUSION: The potential of microbially synthesized nanoparticles, as novel therapeutic agents, is still relatively less explored. In fact, the present study first time demonstrated that a glycolipoprotein secreted by the O. rhizosphaerae strain can be exploited for production of AgNPs which can further be employed to treat infectious diseases. Although this type of polymer has been obtained earlier from marine fungi and bacteria, none of these reports have studied the role of this polymer in AgNPs synthesis and its application in cholera therapy. Interestingly, the microbial GLP-capped AgNPs exhibited antibacterial activity against V. cholerae comparable to ciprofloxacin. Thus the present study may open up new avenues for development of novel therapeutic agents for treatment of infectious diseases. Graphical abstract Development of novel therapeutic agents for treatment of cholera.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cólera/tratamento farmacológico , Glicoproteínas/farmacologia , Lipoproteínas/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Antioxidantes/farmacologia , Biopolímeros/isolamento & purificação , Biopolímeros/farmacologia , Compostos de Bifenilo/química , Difusão Dinâmica da Luz , Sequestradores de Radicais Livres/química , Glicoproteínas/isolamento & purificação , Lipoproteínas/isolamento & purificação , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Filogenia , Picratos/química , RNA Ribossômico 16S/genética , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Ressonância de Plasmônio de Superfície , Temperatura , Vibrio cholerae/efeitos dos fármacos , Vibrio cholerae/ultraestrutura
12.
Int J Biol Macromol ; 265(Pt 2): 131088, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38521315

RESUMO

Curcumin is a multitargeting nutraceutical with numerous health benefits, however, its efficacy is limited due to poor aqueous solubility and reduced bioavailability. While nano-formulation has emerged as an alternative to encounter such issues, it often involves use of toxic solvents. Microbial synthesis may be an innovative solution to address this lacuna. Present study, for the first time, reports exploitation of Aureobasidium pullulans RBF4A3 for production of nano-curcumin. For this purpose, Aureobasidium pullulans RBF4A3 was inoculated in YPD media along with curcumin (0.1 mg/mL) and incubated for 24 h, 48 h, and 72 h. Subsequently, residual sugar, biomass, EPS concentration, curcumin concentration, and curcumin nanoparticle size were measured. As a result, nano-curcumin with an average particle size of 31.63 nm and enhanced aqueous solubility was obtained after 72 h. Further, investigations suggested that pullulan, a reducing polysaccharide, played a significant role in curcumin nano-formulation. Pullulan-mediated nano-curcumin formulation, with an average particle size of 24 nm was achieved with conversion rate of around 59.19 %, suggesting improved aqueous solubility. Additionally, the anti-oxidant assay of the resulting nano-curcumin was around 53.7 % per µg. Moreover, kinetics and thermodynamic studies of pullulan-based nano-curcumin revealed that it followed first-order kinetics and was favored by elevated temperature for efficient bio-conversion. Also, various physico-chemical investigations like FT-IR, NMR, and XRD reveal that pullulan backbone remains intact while forming curcumin nanoparticle. This study may open up new avenues for synthesizing nano-polyphenols through a completely green and solvent free process with plausible diverse applications.


Assuntos
Ascomicetos , Aureobasidium , Curcumina , Glucanos , Fermentação , Curcumina/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Ascomicetos/química , Água/química
13.
Cardiovasc Revasc Med ; 64: 62-67, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38395628

RESUMO

OBJECTIVES: To evaluate the characteristics and outcomes of patients with a chronic total occlusion (CTO) in a Non-ST Elevation Myocardial Infarction (NSTEMI) cohort. BACKGROUND: There is limited data on the clinical characteristics, revascularisation strategies and outcomes of patients presenting with a NSTEMI and a CTO. METHODS: Retrospective analysis of a six-centre percutaneous coronary intervention (PCI) registry in the UK between January 2015 and December 2020 was performed. Patients with a NSTEMI with and without a CTO were compared for baseline characteristics and outcomes. RESULTS: There were 17,355 NSTEMI patients in total of whom 1813 patients had a CTO (10.4 %). Patients with a CTO were more likely to be older (CTO: 67.8 (±11.5) years vs. no CTO: 67.2 (±12) years, p = 0.04), male (CTO: 81.1 % vs.71.9 %, p < 0.0001) with a greater prevalence of cardiovascular risk factors. All-cause mortality at 30 days: HR 2.63, 95 % CI 1.42-4.84, p = 0.002 and at 1 year: HR: 1.87, 95 % CI 1.25-2.81, p = 0.003 was higher in the CTO cohort. CTO patients who underwent revascularisation were younger (Revascularisation 66.4 [±11.7] years vs. no revascularisation 68.4 [±11.4] years, p = 0.001). Patients with failed CTO revascularisation had lower survival (HR 0.21, 95 % CI 0.10-0.42, p < 0.0001). The mean time to revascularisation was 13.4 days. There was variation in attempt at CTO revascularisation between the 6 centres for (16 % to 100 %) with success rates ranging from 65 to 100 %. CONCLUSIONS: In conclusion, the presence of a CTO in NSTEMI patients undergoing PCI was associated with worse in-hospital and long-term outcomes.


Assuntos
Oclusão Coronária , Infarto do Miocárdio sem Supradesnível do Segmento ST , Intervenção Coronária Percutânea , Sistema de Registros , Humanos , Masculino , Feminino , Oclusão Coronária/mortalidade , Oclusão Coronária/terapia , Oclusão Coronária/diagnóstico por imagem , Idoso , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Estudos Retrospectivos , Infarto do Miocárdio sem Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio sem Supradesnível do Segmento ST/terapia , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico por imagem , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Doença Crônica , Medição de Risco , Fatores de Risco , Idoso de 80 Anos ou mais , Reino Unido/epidemiologia
14.
Int J Biol Macromol ; 237: 124057, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36933592

RESUMO

The current study focused on analysing and predicting the effect of physicochemical parameters on the rheological properties of the novel polysaccharide-based bigel. This is the first study to report a bigel fabricated entirely from polysaccharides and develop a neural network to predict the modulation in its rheology. This bi-phasic gel had gellan and κ-carrageenan as the constitutive elements in the aqueous and the organic phase, respectively. Physicochemical studies revealed the influence of organogel in eliciting high mechanical strength and smooth surface morphology to the bigel. Furthermore, variation in physiochemical parameters indicated the bigel's inertness towards change in pH of the system. However, variation in temperature led to a noticeable change in the rheology of the bigel. It was observed that after gradual decline, the bigel regained its original viscosity as the temperature increased beyond 80 °C. Insights from this study can pave way for the development of highly-stable polysaccharide bigels.


Assuntos
Redes Neurais de Computação , Polissacarídeos Bacterianos , Carragenina/química , Viscosidade , Polissacarídeos Bacterianos/química , Concentração de Íons de Hidrogênio , Reologia , Géis
15.
Int J Biol Macromol ; 227: 231-240, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535354

RESUMO

The current study, for the first time, attempts to co-encapsulate Bacillus coagulans spores as probiotics and vitamin B9 in the polysaccharide-based matrix for their targeted delivery. Instead of vegetative cells, probiotic spores were chosen owing to their higher stability. The matrix, tri-composite hydrogel, was synthesized from gellan, κ-carrageenan, and chitosan through self-assembly devoid of chemical cross-linkers. Hence, it was found suitable for application in the co-encapsulation of bioactive compounds. The synthesized hydrogel showed remarkable encapsulation efficiency for folic acid and probiotic spores, both individually and in combination. At acidic pH, loaded hydrogel exhibited 28.42 % and 45.14 % release of spores and folic acid, respectively, which was comparatively lower than the trends observed under neutral and alkaline pH. These results were correlated with the release pattern observed during in vitro digestibility studies. Moreover, spore conversion to vegetative cells and its high colonization were observed in the simulated intestinal phase. Therefore, the matrix maintained viability and stability of co-encapsulated folic acid and bacterial spores in gastric pH while they were slowly released in the intestinal phase. These promising findings pave the way to develop a natural matrix for co-encapsulating various bioactive compounds and probiotics.


Assuntos
Bacillus coagulans , Quitosana , Probióticos , Carragenina/química , Hidrogéis , Quitosana/química , Ácido Fólico , Preparações de Ação Retardada , Esporos Bacterianos , Probióticos/química
16.
Expert Rev Cardiovasc Ther ; 21(7): 501-506, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37269322

RESUMO

INTRODUCTION: Despite advances in stent technology for percutaneous coronary intervention (PCI) in the treatment of coronary disease, these procedures can be complicated by stent failure manifested as intracoronary stent restenosis (ISR). Even with advances in stent technology and medical therapy, this complication is reported to affect around 10% of all percutaneous coronary intervention (PCI) procedures. Depending on stent type (drug-eluting versus bare metal), ISR has subtle differences in mechanism and timing and offers different challenges in diagnosing etiology and subsequent treatment options. AREAS COVERED: This review will be visiting the definition, pathophysiology, and risk factors of ISR. EXPERT OPINION: The evidence behind management options has been illustrated with the aid of real life clinical cases and summarized in a proposed management algorithm.


Assuntos
Reestenose Coronária , Stents Farmacológicos , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Stents Farmacológicos/efeitos adversos , Resultado do Tratamento , Desenho de Prótese , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/etiologia , Stents/efeitos adversos , Fatores de Risco , Constrição Patológica/complicações , Angiografia Coronária/efeitos adversos
17.
Future Cardiol ; 19(6): 353-361, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37449460

RESUMO

Aim: Bifurcation-PCI is performed frequently, although without extensive evidence to back up a definitive solution for its complexity. We set out to identify factors associated with 1- and 12-month mortality after bifurcation-PCI between 2017 and 2021 in our tertiary center in Wales, UK. Results: Of 732 bifurcation PCI cases (mean age 69; 25% female), 67% were in ACS, 42% were left main PCI and 25.3% involved two-stent strategy. 30-day and 12-month mortality were 1.9 and 8.2%, respectively. Age, diabetes, smoking and renal failure are associated with mortality after bifurcation-PCI, while the choice between provisional and 2-stent strategies did not impact mortality/TLR. Conclusion: Awareness of 'real-world' outcomes of bifurcation-PCI should be used for appropriate patient selection, technique planning and procedural consent.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Humanos , Feminino , Idoso , Masculino , Doença da Artéria Coronariana/cirurgia , Intervenção Coronária Percutânea/métodos , Angiografia Coronária , Fatores de Risco , Resultado do Tratamento , Stents
18.
Microb Cell Fact ; 11(1): 39, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22462652

RESUMO

BACKGROUND: Ever increasing demand for fossil fuels is a major factor for rapid depletion of these non-renewable energy resources, which has enhanced the interest of finding out alternative sources of energy. In recent years jatropha seed oil has been used extensively for production of bio-diesel and has shown significant potential to replace petroleum fuels at least partially. De-oiled jatropha seed cake (DOJSC) which comprises of approximately 55 to 65% of the biomass is a byproduct of bio-diesel industry. DOJSC contains toxic components like phorbol esters which restricts its utilization as animal feed. Thus along with the enhancement of biodiesel production from jatropha, there is an associated problem of handling this toxic byproduct. Utilization of DOJSC as a feed stock for production of biochemicals may be an attractive solution to the problem.Pullulan is an industrially important polysaccharide with several potential applications in food, pharmaceuticals and cosmetic industries. However, the major bottleneck for commercial utilization of pullulan is its high cost. A cost effective process for pullulan production may be developed using DOJSC as sole nutrient source which will in turn also help in utilization of the byproduct of bio-diesel industry. RESULTS: In the present study, DOJSC has been used as a nutrient for production of pullulan, in place of conventional nutrients like yeast extract and peptone. Process optimization was done in shake flasks, and under optimized conditions (8% DOJSC, 15% dextrose, 28°C temperature, 200 rpm, 5% inoculum, 6.0 pH) 83.98 g/L pullulan was obtained. The process was further validated in a 5 L laboratory scale fermenter. CONCLUSION: This is the first report of using DOJSC as nutrient for production of an exopolysaccharide. Successful use of DOJSC as nutrient will help in finding significant application of this toxic byproduct of biodiesel industry. This in turn also have a significant impact on cost reduction and may lead to development of a cost effective green technology for pullulan production.


Assuntos
Glucanos/biossíntese , Jatropha/metabolismo , Fermentação , Glucanos/química , Jatropha/química , Energia Renovável , Sementes/química
19.
Microb Cell Fact ; 11: 86, 2012 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-22715848

RESUMO

BACKGROUND: Gold nanoparticles (AuNPs) have found wide range of applications in electronics, biomedical engineering, and chemistry owing to their exceptional opto-electrical properties. Biological synthesis of gold nanoparticles by using plant extracts and microbes have received profound interest in recent times owing to their potential to produce nanoparticles with varied shape, size and morphology. Marine microorganisms are unique to tolerate high salt concentration and can evade toxicity of different metal ions. However, these marine microbes are not sufficiently explored for their capability of metal nanoparticle synthesis. Although, marine water is one of the richest sources of gold in the nature, however, there is no significant publication regarding utilization of marine micro-organisms to produce gold nanoparticles. Therefore, there might be a possibility of exploring marine bacteria as nanofactories for AuNP biosynthesis. RESULTS: In the present study, marine bacteria are exploited towards their capability of gold nanoparticles (AuNPs) production. Stable, monodisperse AuNP formation with around 10 nm dimension occur upon exposure of HAuCl(4) solution to whole cells of a novel strain of Marinobacter pelagius, as characterized by polyphasic taxonomy. Nanoparticles synthesized are characterized by Transmission electron microscopy, Dynamic light scattering and UV-visible spectroscopy. CONCLUSION: The potential of marine organisms in biosynthesis of AuNPs are still relatively unexplored. Although, there are few reports of gold nanoparticles production using marine sponges and sea weeds however, there is no report on the production of gold nanoparticles using marine bacteria. The present work highlighted the possibility of using the marine bacterial strain of Marinobacter pelagius to achieve a fast rate of nanoparticles synthesis which may be of high interest for future process development of AuNPs. This is the first report of AuNP synthesis by marine bacteria.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Ouro/metabolismo , Nanopartículas Metálicas/análise , Água do Mar/microbiologia , Bactérias/classificação , Bactérias/genética , Nanopartículas Metálicas/microbiologia , Dados de Sequência Molecular , Filogenia
20.
ACS Omega ; 7(45): 40724-40739, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36406482

RESUMO

In recent times, nutrition and diet have become prominent health paradigms due to sedentary lifestyle disorders. Preventive health care strategies are becoming increasingly popular instead of treating and managing diseases. A nutraceutical is an innovative concept that offers additional health benefits beyond its fundamental nutritional value. These nutraceuticals have the potential to reduce the exorbitant use of synthetic drugs because the modern medicine approach of treating diseases with high-tech, expensive supplements, and long-term consequences aggravates consumers. However, most nutraceuticals are plant-derived, making them susceptible to degradation and prone to chemical instability, poor solubility, unpleasant taste, and bioactivity loss before absorption to the targeted site. To counteract this problem, the bioavailability of these labile compounds can be maximized by encapsulating them in protective nanocarriers. It is crucial that nanoencapsulation technologies convert bioactive compounds into forms that can be easily combined with functional foods and beverages without adversely affecting their organoleptic properties. In recent years, nanoformulations using food-grade materials, such as polysaccharides, proteins, lipids, etc., have received considerable attention. Among them, microbial polysaccharides are biocompatible, nontoxic, and nonimmunogenic, and most of them are US-FDA approved and can undergo tailored modifications. The nanoformulation of microbial polysaccharide is a relatively new frontier which has several advantages over existing systems. The present article, for the first time, comprehensively reviews microbial polysaccharides-based nanodelivery systems for nutraceuticals and discusses various techno-commercial aspects of these nanotechnological preparations. Moreover, this has also attempted to draw a future research perspective in this area.

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