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1.
Scand J Trauma Resusc Emerg Med ; 32(1): 24, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528572

RESUMEN

BACKGROUND: Major traumatic haemorrhage is potentially preventable with rapid haemorrhage control and improved resuscitation techniques. Although advances in prehospital trauma management, haemorrhage is still associated with high mortality. The aim of this study was to use a recent pragmatic transfusion-based definition of major bleeding to characterize patients at risk of major bleeding and associated outcomes in this cohort after trauma. METHODS: This was a retrospective cohort study including all trauma patients (n = 7020) admitted to a tertiary trauma center from January 2015 to June 2020. The major bleeding cohort (n = 145) was defined as transfusion of 4 units of any blood components (red blood cells, plasma, or platelets) within 2 h of injury. Univariate and multivariable logistic regression analyses were performed to identify risk factors for 24-hour and 30-day mortality post trauma admission. RESULTS: In the major bleeding cohort (n = 145; 145/7020, 2.1% of the trauma population), there were 77% men (n = 112) and 23% women (n = 33), median age 39 years [IQR 26-53] and median Injury Severity Score (ISS) was 22 [IQR 13-34]. Blunt trauma dominated over penetrating trauma (58% vs. 42%) where high-energy fall was the most common blunt mechanism and knife injury was the most common penetrating mechanism. The major bleeding cohort was younger (OR 0.99; 95% CI 0.98 to 0.998, P = 0.012), less female gender (OR 0.66; 95% CI 0.45 to 0.98, P = 0.04), and had more penetrating trauma (OR 4.54; 95% CI 3.24 to 6.36, P = 0.001) than the rest of the trauma cohort. A prehospital (OR 2.39; 95% CI 1.34 to 4.28; P = 0.003) and emergency department (ED) (OR 6.91; 95% CI 4.49 to 10.66, P = 0.001) systolic blood pressure < 90 mmHg was associated with the major bleeding cohort as well as ED blood gas base excess < -3 (OR 7.72; 95% CI 5.37 to 11.11; P < 0.001) and INR > 1.2 (OR 3.09; 95% CI 2.16 to 4.43; P = 0.001). Emergency damage control laparotomy was performed more frequently in the major bleeding cohort (21.4% [n = 31] vs. 1.5% [n = 106]; OR 3.90; 95% CI 2.50 to 6.08; P < 0.001). There was no difference in transportation time from alarm to hospital arrival between the major bleeding cohort and the rest of the trauma cohort (47 [IQR 38;59] vs. 49 [IQR 40;62] minutes; P = 0.17). However, the major bleeding cohort had a shorter time from ED to first emergency procedure (71.5 [IQR 10.0;129.0] vs. 109.00 [IQR 54.0; 259.0] minutes, P < 0.001). In the major bleeding cohort, patients with penetrating trauma, compared to blunt trauma, had a shorter alarm to hospital arrival time (44.0 [IQR 35.5;54.0] vs. 50.0 [IQR 41.5;61.0], P = 0.013). The 24-hour mortality in the major bleeding cohort was 6.9% (10/145). All fatalities were due to blunt trauma; 40% (4/10) high energy fall, 20% (2/10) motor vehicle accident, 10% (1/10) motorcycle accident, 10% (1/10) traffic pedestrian, 10% (1/10) traffic other, and 10% (1/10) struck/hit by blunt object. In the logistic regression model, prehospital cardiac arrest (OR 83.4; 95% CI 3.37 to 2063; P = 0.007) and transportation time (OR 0.95, 95% CI 0.91 to 0.99, P = 0.02) were associated with 24-hour mortality. RESULTS: Early identification of patients at high risk of major bleeding is challenging but essential for rapid definitive haemorrhage control. The major bleeding trauma cohort is a small part of the entire trauma population, and is characterized of being younger, male gender, higher ISS, and exposed to more penetrating trauma. Early identification of patients at high risk of major bleeding is challenging but essential for rapid definitive haemorrhage control.


Asunto(s)
Heridas y Lesiones , Heridas no Penetrantes , Heridas Penetrantes , Humanos , Masculino , Femenino , Adulto , Centros Traumatológicos , Estudios Retrospectivos , Hemorragia/epidemiología , Hemorragia/etiología , Hemorragia/terapia , Resucitación/métodos , Heridas Penetrantes/complicaciones , Heridas no Penetrantes/complicaciones , Heridas no Penetrantes/epidemiología , Heridas no Penetrantes/terapia , Puntaje de Gravedad del Traumatismo , Heridas y Lesiones/epidemiología , Heridas y Lesiones/terapia , Heridas y Lesiones/complicaciones
2.
Catheter Cardiovasc Interv ; 102(7): 1364-1375, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37698335

RESUMEN

BACKGROUND: Extremely large aortic valve anatomy is one of the remaining limitations leading to exclusion of patients for transcatheter aortic valve replacement (TAVR). AIMS: The newly approved Myval 32 mm device is designed for use in aortic annulus areas up to 840 mm2 . Here we want to share the initial worldwide experience with the device. METHODS AND RESULTS: Retrospective data were collected from 10 patients with aortic stenosis and very large annular anatomy (mean area 765.5 mm2 ), who underwent implantation with 32 mm Myval transcatheter heart valve at eight centers. Valve Academic Research Consortium-2 device success was achieved in all cases. Mild paravalvular leak was observed in three patients and two patients required new pacemaker implantation. One patient experienced retroperitoneal hemorrhage caused by the contralateral 6 F sheath and required surgical revision. No device-related complications, stroke, or death from any cause occurred within the 30-day follow-up period. In a studied cohort of 2219 consecutive TAVR-screened patients from a central European site, only 0.27% of patients showed larger anatomy than covered by the 32 mm Myval device by instructions for use without off-label use of overexpansion. This rate was significantly higher for the 34 mm Evolut Pro (1.8%) and 29 mm Sapien 3 (2.1%) devices. CONCLUSIONS: The Myval 32 mm prosthesis showed promising initial results in a cohort of patients who previously had to be excluded from TAVR. It is desirable that all future TAVR systems accommodate larger anatomy to allow optimal treatment of all patients.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Diseño de Prótesis , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos
3.
Turk J Surg ; 36(3): 284-290, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33778384

RESUMEN

OBJECTIVES: Pilonidal sinus disease (PSD) has been a recognized pathology for the past 188 years. We studied whether scientific interest in this common disease has grown or declined over time. Our investigation included analysis of the world literature between 1833 and 2018. MATERIAL AND METHODS: A PubMed search was conducted to identify all publications on pilonidal sinus disease, broken down by country, year of publication and number of patients included or described. RESULTS: The number of patients studied has been increasing, with date of more than 10,000 patients published per decade since 1970, and the total number of affected patients exceeding n=40,000 in 2010 and Turkey leads the research, contributing 39% of the Mediterranean patients and 18% of the patients globally, while Italy provides 26% of the Mediterranean patients and 12% of the global total. Flap studies have increased, whereas primary open treatment studies have decreased from 40% in 1940 to less than 10% at present. Twenty percent of the studies performed today report primary median approaches, and the number of randomized controlled trials has increased. CONCLUSION: Surgeons in Turkey currently publish the lion´s share of the pilonidal sinus literature.

4.
Sci Rep ; 9(1): 18477, 2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31811255

RESUMEN

We investigate superfluid phase transitions of asymmetric nuclear matter at finite temperature (T) and density (ρ) with a low proton fraction (Yp ≤ 0.2), which is relevant to the inner crust and outer core of neutron stars. A strong-coupling theory developed for two-component atomic Fermi gases is generalized to the four-component case, and is applied to the system of spin-1/2 neutrons and protons. The phase shifts of neutron-neutron (nn), proton-proton (pp) and neutron-proton (np) interactions up to k = 2 fm-1 are described by multi-rank separable potentials. We show that the critical temperature [Formula: see text] of the neutron superfluidity at Yp = 0 agrees well with Monte Carlo data at low densities and takes a maximum value [Formula: see text]= 1.68 MeV at [Formula: see text] with ρ0 = 0.17 fm-3. Also, the critical temperature [Formula: see text] of the proton superconductivity for Yp ≤ 0.2 is substantially suppressed at low densities due to np-pairing fluctuations, and starts to dominate over [Formula: see text] only above [Formula: see text](0.77) for Yp = 0.1(0.2), and (iii) the deuteron condensation temperature [Formula: see text] is suppressed at Yp ≤ 0.2 due to a large mismatch of the two Fermi surfaces.

5.
PLoS One ; 13(7): e0200552, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29995965

RESUMEN

Nano scanning Auger microscopy (NanoSAM) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) have been used in materials science research for some time, but NanoSAM, in particular, has only recently been applied to biological specimens. Here, the first concurrent utilization of NanoSAM, TOF-SIMS and microscopic techniques for the examination of a standard beverage fermentation strain of Saccharomyces pastorianus uncovered the presence of intracellular networks of CO2 in fermenting cells. Respiring cells produced few bubbles and instead had large internal vacuolar structures. Transmission electron microscopy analysis also showed osmiophilic layers at the cell exterior of fermenting cells that became more prevalent with fermentation duration, while osmiophilic layers were largely absent in respiring cells. TOF-SIMS analysis showed a compositional difference at the exterior and interior of SMA cells and between fermenting and respiring cells. Fermenting cells also appeared to have different 3-OH oxylipin profiles compared to respiring cells based upon examination with immunofluorescence microscopy. The results of this work and further study using these materials science techniques will substantially enhance our understanding of the chemical, ultrastructural and metabolic changes that occur in fermentation yeasts.


Asunto(s)
Saccharomyces/metabolismo , Saccharomyces/ultraestructura , Espectrometría de Masas , Microscopía Electrónica de Rastreo
6.
Heart Lung Circ ; 27(2): 212-218, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28652031

RESUMEN

BACKGROUND: Adenosine induced hyperaemic fractional flow reserve (aFFR) is a validated predictor of clinical outcome and part of routine interventional practice. Protocol issues associated with the adenosine infusion limit the use of aFFR in clinical practice. Contrast medium induced hyperaemic FFR (cFFR) is a simpler procedure from a practical standpoint. We compared the two in a real world setting. METHODS: We analysed 76 patients that had both cFFR and aFFR assessment of 100 angiographically indeterminate coronary stenosis. cFFR was performed with intracoronary contrast medium injections (10ml for left coronary lesions and 8ml for right coronary lesions). The diagnostic performance of cFFR was analysed and compared to the gold standard aFFR. RESULTS: Mean cFFR was 0.87 (±0.07) and mean aFFR was 0.84 (±0.08). Bland-Altman analysis revealed a close agreement between cFFR and aFFR (0.035±0.032; 95% CI: -0.028 to 0.098) and good linear correlation (r=0.92, r2=0.86; p<0.0001). Using cFFR cut-off values of ≤0.83 in predicting an aFFR value of ≤0.80 or a cFFR value ≥0.88, predicting an aFFR value of >0.80 yielded a sensitivity of 100%, specificity of 96.1%, positive predictive value of 92.3%, negative predictive value of 100% and diagnostic accuracy of 96%. Only 24% of cFFR values were in the 0.84 to 0.87 range. CONCLUSION: Contrast medium induced hyperaemic FFR as an initial assessment may limit the need for adenosine to when cFFR falls in the 0.84 to 0.87 range. The use of adenosine infusion potentially could have been avoided in the majority of patients in this study.


Asunto(s)
Angiografía por Tomografía Computarizada/estadística & datos numéricos , Medios de Contraste/farmacología , Angiografía Coronaria/estadística & datos numéricos , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Reserva del Flujo Fraccional Miocárdico/fisiología , Anciano , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC
7.
Ann Emerg Med ; 68(1): 93-102.e1, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26947800

RESUMEN

STUDY OBJECTIVE: A 2-hour accelerated diagnostic pathway based on the Thrombolysis in Myocardial Infarction score, ECG, and troponin measures (ADAPT-ADP) increased early discharge of patients with suspected acute myocardial infarction presenting to the emergency department compared with standard care (from 11% to 19.3%). Observational studies suggest that an accelerated diagnostic pathway using the Emergency Department Assessment of Chest Pain Score (EDACS-ADP) may further increase this proportion. This trial tests for the existence and size of any beneficial effect of using the EDACS-ADP in routine clinical care. METHODS: This was a pragmatic randomized controlled trial of adults with suspected acute myocardial infarction, comparing the ADAPT-ADP and the EDACS-ADP. The primary outcome was the proportion of patients discharged to outpatient care within 6 hours of attendance, without subsequent major adverse cardiac event within 30 days. RESULTS: Five hundred fifty-eight patients were recruited, 279 in each arm. Sixty-six patients (11.8%) had a major adverse cardiac event within 30 days (ADAPT-ADP 29; EDACS-ADP 37); 11.1% more patients (95% confidence interval 2.8% to 19.4%) were identified as low risk in EDACS-ADP (41.6%) than in ADAPT-ADP (30.5%). No low-risk patients had a major adverse cardiac event within 30 days (0.0% [0.0% to 1.9%]). There was no difference in the primary outcome of proportion discharged within 6 hours (EDACS-ADP 32.3%; ADAPT-ADP 34.4%; difference -2.1% [-10.3% to 6.0%], P=.65). CONCLUSION: There was no difference in the proportion of patients discharged early despite more patients being classified as low risk by the EDACS-ADP than the ADAPT-ADP. Both accelerated diagnostic pathways are effective strategies for chest pain assessment and resulted in an increased rate of early discharges compared with previously reported rates.


Asunto(s)
Dolor en el Pecho/diagnóstico , Vías Clínicas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Dolor en el Pecho/etiología , Servicio de Urgencia en Hospital , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Alta del Paciente/estadística & datos numéricos , Factores de Riesgo , Factores de Tiempo , Adulto Joven
8.
Folia Microbiol (Praha) ; 61(4): 319-28, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26658947

RESUMEN

Coniochaeta pulveracea is a dimorphic lignicolous fungus that has mostly been isolated from decaying wood. However, relatively little work was conducted on the conditions for the dimorphic switch or the biological interactions of the fungus in its yeast-like microcyclic growth phase. Therefore, in this study, the microcyclic conidiation of C. pulveracea strains and representatives of the closely related species, Coniochaeta boothii and Coniochaeta subcorticalis, was studied under different environmental conditions. The strains were found to exhibit hyphal growth on solid substrates and underwent a dimorphic switch to produce microcycle conidiation upon transfer to a liquid medium which differed in physico-chemical composition compared to the original solid medium. Factors that were found to contribute to this dimorphic switch were temperature, pH and the presence of complex nitrogen sources such as casamino acids and peptone in the medium. However, C. pulveracea showed intraspecific differences with regard to its response to changes in the physico-chemical environment. The interactions of microcyclic Coniochaeta strains with selected yeasts, such as representatives of Meyerozyma guilliermondii and Cryptococcus neoformans, were subsequently studied in complex liquid media and it was found that, depending on medium composition, the microcyclic Coniochaeta exerted different effects on the different yeasts strains. In some co-cultures, a positive effect on yeast growth was observed, whilst in other cases microcyclic Coniochaeta inhibited yeast growth.


Asunto(s)
Ascomicetos/citología , Ascomicetos/crecimiento & desarrollo , Hifa/citología , Hifa/crecimiento & desarrollo , Esporas Fúngicas/citología , Esporas Fúngicas/crecimiento & desarrollo , Ascomicetos/efectos de los fármacos , Ascomicetos/efectos de la radiación , Cryptococcus neoformans/crecimiento & desarrollo , Medios de Cultivo/química , Concentración de Iones de Hidrógeno , Hifa/efectos de los fármacos , Hifa/efectos de la radiación , Interacciones Microbianas , Compuestos de Nitrógeno/metabolismo , Saccharomycetales/crecimiento & desarrollo , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/efectos de la radiación , Temperatura
9.
Rapid Commun Mass Spectrom ; 28(5): 505-19, 2014 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-24497289

RESUMEN

RATIONALE: The speciation of the purely inorganic [PtCl6-n Brn](2-) (n = 0-6) anions and their corresponding mono-aquated [PtCl5-n Brn (H2O)](-) (n = 0-5) anions is of considerable importance to the precious metal refining and recycling industry, to ensure optimum recovery and separation efficiencies. Speciation of platinum complexes present in precursor solutions used for the preparation of precious metal nano-crystals of defined size and morphology appears also to be important. The various possible Pt(IV) complex anions in dilute aqueous can be characterized using ion-pairing reversed-phase high-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOFMS). METHODS: Ion-pairing reversed-phase ultra-high-performance LC separation of the Pt(IV) complex anions present in aqueous solutions prior to detection by means of high-resolution ESI-Q-TOFMS using a low ESI source cone voltage (5 V) allows for the clear identification of all the platinum complexes from the characteristic pattern of fragment ions (m/z), presumably generated by 'reductive conversion' in the ESI source of the mass spectrometer. Sufficient chromatographic resolution for the series of Pt(IV) complexes is achieved using the (n-butyl)3 NH(+) ion generated in a formic acid/water/methanol (pH ~3.5) mobile phase. This mobile phase composition facilitates a low-background for optimal ESI-Q-TOFMS detection with enhanced sensitivity. RESULTS: Direct-infusion mass spectrometry of the inorganic platinum complexes in aqueous solution is impractical due to their low volatility, but more importantly as a result of the very extensive series of fragment ions generated in the ESI source, which leads to virtually uninterpretable mass spectra. However, with prior separation, and by using low ESI cone voltages (5 V), the mass spectra of the separated analyte ions show simpler and systematic fragmentation patterns [Pt(IV) X5](-) → [Pt(III) X4 ](-) → [Pt(II) X3](-) → [Pt(I)X2 ](-) (X = Cl(-) and Br(-)), resulting in clear assignments. This methodology facilitates the characterization of the partially aquated [PtCl5-n Brn (H2O)](-) (n = 0-5) anions derived from the homo- and heteroleptic [PtCl6-n Brn](2-) (n = 0-6) anions, in equilibrated solutions at low concentrations. CONCLUSIONS: Speciation of homo- and heteroleptic [PtCl6-n Brn](2-) (n = 0-6) anions, together with some of their partially aquated [PtCl5-n Brn (H2O)](-) (n = 0-5) species in dilute solution, can successfully be carried out by means of prior ion-pairing reversed-phase LC separation coupled to high-resolution ESI-Q-TOFMS at low ESI cone-voltage settings.

10.
Can J Microbiol ; 59(6): 413-6, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23750956

RESUMEN

According to literature, the elongated ascospores of Dipodascopsis uninucleata var. uninucleata exhibit smart movement when forcefully ejected from bottle-shaped asci. This type of movement is defined as the unique patterns of non-random movement of ascospores with specialized morphology thereby facilitating release from asci. Smart movement is required to actively release ascospores individually through the narrow ascus neck, without causing an obstruction and blocking ascospore release. However, little is known about the propulsion mechanism of this cannon-type release system. We show that asci of this yeast contain a central channel (barrel) filled with ascospores. These are surrounded by a sheath-like structure that lines the inner surface of the ascus wall. We found that this sheath is responsible for forcing the naked ascospores out of the ascus by exerting turgor pressure from the bottom towards the tip of the ascus. This cannon firing system is in contrast to that found in Dipodascus geniculatus, where no sheaths lining the ascus interior were observed. Instead, sheaths were found enveloping each ascospore.


Asunto(s)
Saccharomycetales/citología , Saccharomycetales/fisiología , Esporas Fúngicas/fisiología , Presión , Esporas Fúngicas/ultraestructura
11.
Sensors (Basel) ; 12(10): 13058-74, 2012 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-23201985

RESUMEN

In this study the mitochondrion is regarded as a target to reveal compounds that may be used to combat various diseases. Consequently, the sexual structures of yeasts (with high mitochondrial activity) were identified as sensors to screen for various anti-mitochondrial drugs that may be toxic to humans and that are directed, amongst others, against fungal diseases and cancer. Strikingly, these sensors indicated that chloroquine is a potent pro-mitochondrial drug which stimulated yeast sexual reproduction. In addition, these sensors also showed that some Non-Steroidal Anti-Inflammatory drugs (NSAIDs), anti-malarial drugs, antifungal and anticancer drugs are anti-mitochondrial. These yeast sensor bio-assays may fast track studies aimed at discovering new drugs as well as their mechanisms and should now be further evaluated for selectivity towards anti-/ pro-mitochondrials, fertility drugs and contraceptives, using in vitro, in vivo, in silico and omics research.


Asunto(s)
Bioensayo/métodos , Técnicas Biosensibles/métodos , Cloroquina/aislamiento & purificación , Descubrimiento de Drogas/métodos , Levaduras/fisiología , Antifúngicos/aislamiento & purificación , Antineoplásicos/aislamiento & purificación , Eremothecium/fisiología , Humanos , Lipomyces/fisiología , Mitocondrias/efectos de los fármacos
12.
FEMS Yeast Res ; 12(7): 867-9, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23020660

RESUMEN

Current paradigms assume that gas bubbles cannot be formed within yeasts although these workhorses of the baking and brewing industries vigorously produce and release CO(2) gas. We show that yeasts produce gas bubbles that fill a significant part of the cell. The missing link between intracellular CO(2) production by glycolysis and eventual CO(2) release from cells has therefore been resolved. Yeasts may serve as model to study CO(2) behavior under pressurized conditions that may impact on fermentation biotechnology.


Asunto(s)
Dióxido de Carbono/metabolismo , Citoplasma/metabolismo , Gases/metabolismo , Saccharomyces/metabolismo , Glucólisis
14.
Biochim Biophys Acta ; 1820(10): 1463-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22609876

RESUMEN

BACKGROUND: Polyunsaturated fatty acids (PUFAs) have antifungal properties, but the mode by which they induce their action is not always clear. The aim of the study was to investigate apoptosis as a mode of action of antifungal PUFAs (stearidonic acid, eicosapentaenoic acid and docosapentaenoic acid) which are inhibitory towards biofilm formation of C. albicans and C. dubliniensis. METHODS: Candida biofilms were grown in the absence or presence of 1mM PUFAs (linoleic acid, stearidonic acid, eicosapentaenoic acid, docosapentaenoic acid) for 48h at 37°C. The effect of these PUFAs on the membrane fatty acid profile and unsaturation index, oxidative stress, mitochondrial transmembrane potential and apoptosis was evaluated. RESULTS: When biofilms of C. albicans and C. dubliniensis were exposed to certain PUFAs there was an increase in unsaturation index of the cellular membranes and accumulation of intracellular reactive oxygen species (ROS). This resulted in apoptosis, evidenced by reduced mitochondrial membrane potential and nuclear condensation and fragmentation. The most effective PUFA was stearidonic acid. CONCLUSIONS: The resultant cell death of both C. albicans and C. dubliniensis is due to apoptosis. GENERAL SIGNIFICANCE: Due to the increase in drug resistance, alternative antifungal drugs are needed. A group of natural antifungal compounds is PUFAs. However, understanding their mechanisms of action is important for further use and development of these compounds as antifungal drugs. This paper provides insight into a possible mode of action of antifungal PUFAs.


Asunto(s)
Apoptosis/efectos de los fármacos , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida/efectos de los fármacos , Ácidos Grasos Insaturados/farmacología , Biopelículas/crecimiento & desarrollo , Candida/crecimiento & desarrollo , Candida/metabolismo , Candida/fisiología , Candida albicans/crecimiento & desarrollo , Candida albicans/metabolismo , Candida albicans/fisiología , Fragmentación del ADN/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Fosfolípidos/metabolismo , Especies Reactivas de Oxígeno/metabolismo
15.
Anal Chim Acta ; 704(1-2): 154-61, 2011 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-21907033

RESUMEN

A robust reversed phase ion-pairing RP-HPLC method has been developed for the unambiguous speciation and quantification of all possible homoleptic and heteroleptic octahedral platinum(IV) [PtCl(6-n)Br(n)](2-) (n=0-6) as well as the corresponding platinum(II) [PtCl(4-n)Br(n)](2-) (n=0-4) complex anions using UV/Vis detection. High resolution (195)Pt NMR in more concentrated solutions of these Pt(II/IV) complexes (≥50 mM) served to validate the chromatographic peak assignments, particularly in the case of the possible stereoisomers of Pt(II/IV) complex anions. By means of IP-RP-HPLC coupled to ICP-MS or ICP-OES it is possible to accurately determine the relative concentrations of all possible Pt(II/IV) species in these solutions, which allows for the accurate determination of the photometric characteristics (λ(max) and ɛ) of all the species in this series, by recording of the UV/Vis absorption spectra of all eluted species, using photo-diode array, and quantification with ICP-MS or ICP-OES. With this method it is readily possible to separate and estimate the concentrations of the various stereoisomers which are present in these solutions at sub-millimolar concentrations, such as cis- and trans-[PtCl(4)Br(2)](2-), fac- and mer-[PtCl(3)Br(3)](2-) and cis- and trans-[PtCl(2)Br(4)](2-) for Pt(IV), and cis- and trans-[PtCl(2)Br(2)](2-) in the case of Pt(II). All mixed halide Pt(II) and Pt(IV) species can be separated and quantified in a single IP-RP-HPLC experiment, using the newly obtained photometric molar absorptivities, ɛ, determined herein at given wavelengths.

16.
Mar Drugs ; 8(10): 2597-604, 2010 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-21116408

RESUMEN

The effect of marine polyunsaturated fatty acids on biofilm formation by the human pathogens Candida albicans and Candida dubliniensis was investigated. It was found that stearidonic acid (18:4 n-3), eicosapentaenoic acid (20:5 n-3), docosapentaenoic acid (22:5 n-3) and docosahexaenoic acid (22:6 n-3) have an inhibitory effect on mitochondrial metabolism of both C. albicans and C. dubliniensis and that the production of biofilm biomass by C. dubliniensis was more susceptible to these fatty acids than C. albicans. Ultrastructural differences, which may be due to increased oxidative stress, were observed between treated and untreated cells of C. albicans and C. dubliniensis with formation of rough cell walls by both species and fibrillar structures in C. dubliniensis. These results indicate that marine polyunsaturated fatty acids may be useful in the treatment and/or prevention of biofilms formed by these pathogenic yeasts.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Candida albicans/fisiología , Candida/fisiología , Ácidos Grasos Insaturados/farmacología , Animales , Biopelículas/efectos de los fármacos , Biomasa , Candida/crecimiento & desarrollo , Candida/ultraestructura , Candida albicans/crecimiento & desarrollo , Candida albicans/ultraestructura , Pared Celular/ultraestructura , Ácidos Grasos Insaturados/análisis , Mitocondrias/metabolismo , Estrés Oxidativo , Agua de Mar
17.
Can J Microbiol ; 56(11): 883-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21076478

RESUMEN

The oleaginous fungi Cryptococcus curvatus and Mucor circinelloides were used to determine the effect of palm oil breakdown products, measured as polymerized triglycerides (PTGs), on lipid turnover and on fungal growth and morphology. In M. circinelloides, we found after 7 days of growth, a decrease in biomass and in lipid utilization and accumulation at increased PTG levels, both at low and neutral pH. In C. curvatus, there was also a decrease in lipid utilization and biomass production at increased PTG levels, at both low and neutral pH. However, an increase in oil accumulation was observed at low pH while it remained similar at neutral pH for all PTG levels tested. Hairy and warty protuberances on the cell surface were observed when C. curvatus was grown on oils with 15% and 45% PTGs, respectively. Using nano scanning Auger microscopy, we found no evidence to suggest a difference in elemental composition of the surfaces of the warty protuberances compared with the rest of the cell wall surface. We conclude that the warty protuberances are outgrowths of cell walls and that the changes observed in lipid turnover in both fungi are due to the presence of palm oil breakdown products.


Asunto(s)
Cryptococcus/metabolismo , Metabolismo de los Lípidos , Mucor/metabolismo , Aceites de Plantas/metabolismo , Biomasa , Cryptococcus/crecimiento & desarrollo , Cryptococcus/ultraestructura , Concentración de Iones de Hidrógeno , Mucor/crecimiento & desarrollo , Mucor/ultraestructura , Aceite de Palma , Triglicéridos/metabolismo , Triglicéridos/farmacología
18.
Fungal Biol ; 114(7): 515-27, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20943163

RESUMEN

Pineapple (Ananas comosus) is native to South America and widely planted as a fruit crop in the tropics and sub-tropics. This plant is susceptible to a number of fungal diseases of which the most severe is fusariosis. The disease is caused by Fusarium guttiforme and occurs only in South and Central America. The occurrence of a similar disease on pineapples in South Africa has prompted a re-evaluation of the Fusarium sp. associated with pineapple fruit rot. Phylogenetic relationships of isolates from pineapples collected in Brazil and South Africa were assessed based on sequence data for the translation elongation factor-1-α, histone H3 and ß-tubulin gene regions. Analyses showed that the South African isolates represent a species distinct from Brazilian isolates. The South African isolates are characterised by a concentration of aerial mycelium at the centres of the colonies, different to the Brazilian isolates that have an even distribution of aerial mycelium. Both phylogenetic and morphological data show that the disease on pineapple in South Africa is caused by a new Fusarium species described here as F. ananatum sp. nov.


Asunto(s)
Ananas/microbiología , Fusarium/clasificación , Gibberella/clasificación , Enfermedades de las Plantas/microbiología , Brasil , Frutas/microbiología , Proteínas Fúngicas/genética , Fusarium/genética , Fusarium/aislamiento & purificación , Gibberella/genética , Gibberella/aislamiento & purificación , Datos de Secuencia Molecular , Factor 1 de Elongación Peptídica/genética , Filogenia , Sudáfrica
19.
J Pediatr Surg ; 45(10): 2068-70, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20920733

RESUMEN

We report 2 human immunodeficiency virus-positive patients with refractory esophageal strictures secondary to candidiasis. They presented with progressive dysphagia and had suffered from oropharyngeal and/or esophageal candidiasis within the preceding 3 months. Both failed conservative management of these strictures, including systemic antifungal therapy, administration of proton pump inhibitors, and numerous attempts at stricture dilation, ultimately progressing to open transhiatal esophagectomy. Although challenging in the immunocompromised host, successful treatment of these strictures by gastric interposition is achievable with minimal morbidity.


Asunto(s)
Estenosis Esofágica/cirugía , Esofagectomía/métodos , Estómago/cirugía , Infecciones Oportunistas Relacionadas con el SIDA/complicaciones , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Anastomosis Quirúrgica/métodos , Candidiasis/complicaciones , Cateterismo/métodos , Estenosis Esofágica/etiología , Unión Esofagogástrica/cirugía , Esofagoscopía , Esofagostomía/métodos , Esófago/cirugía , Gastrostomía/métodos , Seropositividad para VIH , Humanos , Lactante , Masculino , Resultado del Tratamiento
20.
Can J Microbiol ; 55(12): 1392-6, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20029531

RESUMEN

It is known that acetylsalicylic acid, an anti-inflammatory and anti-mitochondrial drug, targets structure development and functions of yeasts depending on elevated levels of mitochondrial activity. Using antibody probes, we previously reported that sporangia of Mucor circinelloides also contain increased mitochondrial activity, yielding high levels of 3-hydroxyoxylipins. This was, however, not found in Mortierella alpina (subgenus Mortierella). In this study we report that acetylsalicylic acid (aspirin) also targets sporangium development of Mucor circinelloides selectively, while hyphae with lower levels of mitochondrial activity are more resistant. Similar results were obtained when the anti-inflammatory compounds benzoic acid, ibuprofen, indomethacin, and salicylic acid were tested. The anti-inflammatory drugs exerted similar effects on this dimorphic fungus as found under oxygen-limited conditions. Interestingly, sporangium development of Mortierella alpina was found not to be selectively targeted by these drugs. Mortierella alpina, which could not exhibit dimorphic growth under oxygen-limited conditions, was also more sensitive to the anti-inflammatory drugs when compared with Mucor circinelloides. These results prompt further research to assess the applicability of these antimitochondrial antifungals to protect plants and animals against Mucor infections.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Antifúngicos/farmacología , Aspirina/farmacología , Mitocondrias/efectos de los fármacos , Mucor/efectos de los fármacos , Animales , Ácido Benzoico/farmacología , Ibuprofeno/farmacología , Indometacina/farmacología , Mortierella/efectos de los fármacos , Mortierella/crecimiento & desarrollo , Mucor/crecimiento & desarrollo , Mucormicosis/prevención & control , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Ácido Salicílico/farmacología
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