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The interest in polymers with high thermal conductivity increased much because of their inherent properties such as low density, low cost, flexibility, and good chemical resistance. However, it is challenging to engineer plastics with good heat transfer characteristics, processability, and required strength. Improving the degree of the chain alignment and forming a continuous thermal conduction network is expected to enhance thermal conductivity. This research aimed to develop polymers with a high thermal conductivity that can be interesting for several applications. Two polymers, namely poly(benzofuran-co-arylacetic acid) and poly(tartronic-co-glycolic acid), with high thermal conductivity containing microscopically ordered structures were prepared by performing enzyme-catalyzed (Novozyme-435) polymerization of the corresponding α-hydroxy acids 4-hydroxymandelic acid and tartronic acid, respectively. A comparison between the polymer's structure and heat transfer obtained by mere thermal polymerization before and enzyme-catalyzed polymerization will now be discussed, revealing a dramatic increase in thermal conductivity in the latter case. The polymer structures were investigated by FTIR spectroscopy, nuclear magnetic resonance (NMR) spectroscopy in liquid- and solid-state (ss-NMR), and powder X-ray diffraction. The thermal conductivity and diffusivity were measured using the transient plane source technique.
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Lipasa , Polímeros , Polímeros/química , Conductividad Térmica , Espectroscopía de Resonancia MagnéticaRESUMEN
L-polylactic acid (PLA), a semi-crystalline aliphatic polyester, is one of the most manufactured biodegradable plastics worldwide. The objective of the study was to obtain L-polylactic acid (PLA) from lignocellulosic plum biomass. Initially, the biomass was processed via pressurized hot water pretreatment at a temperature of 180 °C for 30 min at 10 MPa for carbohydrate separation. Cellulase and the beta-glucosidase enzymes were then added, and the mixture was fermented with Lacticaseibacillus rhamnosus ATCC 7469. The resulting lactic acid was concentrated and purified after ammonium sulphate and n-butanol extraction. The productivity of L-lactic acid was 2.04 ± 0.18 g/L/h. Then, the PLA was synthesized in two stages. Firstly, lactic acid was subjected to azeotropic dehydration at 140 °C for 24 h in the presence of xylene, using SnCl2 (0.4 wt.%) as a catalyst, resulting in lactide (CPLA). Secondly, microwave-assisted polymerization was carried out at 140 °C for 30 min with 0.4 wt.% SnCl2. The resulting powder was purified with methanol to produce PLA with 92.1% yield. The obtained PLA was confirmed using electrospray ionization mass spectrometry, nuclear magnetic resonance, thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. Overall, the resulting PLA can successfully replace the traditional synthetic polymers used in the packaging industry.
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Ácido Láctico , Microondas , Ácido Láctico/química , Poliésteres/químicaRESUMEN
Combination HIV prevention covers a range of biomedical, behavioral, and socio-structural interventions. Despite the growing availability of pre-exposure prophylaxis (PrEP), it is not always accessible in European Centre for Disease Prevention and Control reporting countries and may not meet the needs of all at-risk populations. Based on the Flash! PrEP in Europe data, multiple correspondence analysis and hierarchical clustering were used to identify patterns in HIV prevention strategies among 9980 men who have sex with men (MSM). PrEP interest was evaluated among four identified clusters: (A) "high condom use, sometimes Treatment as Prevention (TasP)"; (B) "mix of methods, infrequent condom use"; (C) "high condom use, tendency to choose partners based on serological status" and (D) "moderate use of condoms mixed with other prevention strategies". Clusters B and D had higher PrEP interest. These results suggest that MSM use a range of behavioral and biomedical risk reduction strategies that are often combined. On-demand PrEP may meet the needs of MSM who infrequently use condoms and other prevention methods.
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Fármacos Anti-VIH , Infecciones por VIH , Minorías Sexuales y de Género , Fármacos Anti-VIH/uso terapéutico , Condones , Europa (Continente) , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Humanos , Masculino , Conducta de Reducción del Riesgo , Conducta Sexual , Parejas SexualesRESUMEN
In the context of an increased interest in the abatement of CO2 emissions generated by industrial activities, CO2 hydrogenation processes show an important potential to be used for the production of valuable compounds (methane, methanol, formic acid, light olefins, aromatics, syngas and/or synthetic fuels), with important benefits for the decarbonization of the energy sector. However, in order to increase the efficiency of the CO2 hydrogenation processes, the selection of active and selective catalysts is of utmost importance. In this context, the interest in graphene-based materials as catalysts for CO2 hydrogenation has significantly increased in the last years. The aim of the present paper is to review and discuss the results published until now on graphene-based materials (graphene oxide, reduced graphene oxide, or N-dopped graphenes) used as metal-free catalysts or as catalytic support for the thermocatalytic hydrogenation of CO2. The reactions discussed in this paper are CO2 methanation, CO2 hydrogenation to methanol, CO2 transformation into formic acid, CO2 hydrogenation to high hydrocarbons, and syngas production from CO2. The discussions will focus on the effect of the support on the catalytic process, the involvement of the graphene-based support in the reaction mechanism, or the explanation of the graphene intervention in the hydrogenation process. Most of the papers emphasized the graphene's role in dispersing and stabilizing the metal and/or oxide nanoparticles or in preventing the metal oxidation, but further investigations are needed to elucidate the actual role of graphenes and to propose reaction mechanisms.
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Four N-doped graphene materials with a nitrogen content ranging from 8.34 to 13.1 wt.% are prepared by the ball milling method. This method represents an eco-friendly mechanochemical process that can be easily adapted for industrial-scale productivity and allows both the exfoliation of graphite and the synthesis of large quantities of functionalized graphene. These materials are characterized by transmission and scanning electron microscopy, thermogravimetry measurements, X-ray powder diffraction, X-ray photoelectron and Raman spectroscopy, and then, are tested towards the oxygen reduction reaction by cyclic voltammetry and rotating disk electrode methods. Their responses towards ORR are analysed in correlation with their properties and use for the best ORR catalyst identification. However, even though the mechanochemical procedure and the characterization techniques are clean and green methods (i.e., water is the only solvent used for these syntheses and investigations), they are time consuming and, generally, a low number of materials can be prepared, characterized and tested. In order to eliminate some of these limitations, the use of regression learner and reverse engineering methods are proposed for facilitating the optimization of the synthesis conditions and the materials' design. Thus, the machine learning algorithms are applied to data containing the synthesis parameters, the results obtained from different characterization techniques and the materials response towards ORR to quickly provide predictions that allow the best synthesis conditions or the best electrocatalysts' identification.
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Pt/UiO-66 nanocomposites with platinum target concentration of 3 wt.% were prepared by 3 preparation methods, characterized and tested in the CO2 methanation process. Choice of the microporous UiO-66 metal-organic framework (Zr6O4(OH)4 with 1,4-benzene-dicarboxylate ligand) as catalytic support was motivated by the CO2 chemisorption capacity (proven by CO2-TPD profiles), large specific surface area (1477 m²/g) which favors a high dispersion of metal nanoparticles and good thermal stability. The preparation methods for the Pt/UiO-66 nanocomposites are: (1) wetimpregnation followed by reduction in H2 at 200 °C for 2 h; (2) wet-impregnation followed by reduction with an aqueous solution of NaBH4; and (3) "double-solvent" method, followed by reduction with NaBH4. The UiO-66 based nanocomposites were characterized by N2 adsorption-desorption (BET method), XRD, and SEM/TEM. The Pt/UiO-66 catalyst prepared by method 3 was chosen for catalytic testing due to its highest surface area, smallest platinum nanoparticles (PtNPs) size, the localization of PtNPs both on the grain's internal and external surface and best thermal stability in the desired temperature range. Its capacity to adsorb and activate CO2 and H2 was evaluated in thermo-programmed desorption experiments (H2-TPD and CO2-TPD). Hydrogen is molecularly adsorbed, while CO2 is adsorbed both molecularly and dissociatively. The catalytic performance in the CO2 methanation process was evaluated by Temperature Programmed Reactions (TPRea, 2 °C/min, 30-350 °C), at atmospheric pressure. The best results were obtained at 350 °C, CO2:H2 molar ratio of 1:5.2 and GHSV â 1650 h-1. In these conditions CO2 conversion is almost 50% and CH4 selectivity is 36%, the rest of the converted CO2 being transformed in CO.
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L-poly(lactic acid), poly(3-hydroxybutyrate), and poly-hydroxybutyrate-co-hydroxyvalerate are biodegradable polymers that can be obtained from renewable biomass sources. The aim of this study was to develop three types of environmentally friendly film biocomposites of altered microstructure by combining each of the above-mentioned polymers with cellulose nanocrystal fillers and further processing the resulting materials via space-confined solvent vapor annealing. Cellulose was previously obtained from renewable biomass and further converted to cellulose nanocrystals by hydrolysis with the lactic acid. The solutions of biodegradable polymers were spin-coated onto solid substrates before and after the addition of cellulose nanocrystals. The obtained thin film composites were further processed via space-confined solvent vapor annealing to eventually favor their crystallization and, thus, to alter the final microstructure. Indeed, atomic force microscopy studies have revealed that the presence of cellulose nanocrystals within a biodegradable polymer matrix promoted the formation of large crystalline structures exhibiting fractal-, spherulitic- or needle-like morphologies.
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Tea is the most consumed drink worldwide due to its pleasant taste and various beneficial effects on human health. This paper assesses the physicochemical analysis of different varieties of tea (leaves, flowers, and instant) after prior drying and fine grinding. The thermal decomposition behavior of the tea components shows that the tea has three stages of decomposition, depending on temperature. The first stage was attributed to the volatilization of water, while the second stage involved the degradation of volatiles, polyphenols, and fatty acids. The degradation of cellulose, hemicellulose, and lignin content occurs at the highest temperature of 400 °C in the third stage. A total of 66 volatile compounds, divided into eight classes, were identified in the tea samples. The volatile compounds were classified into nine odor classes: floral, fruity, green, sweet, chemical, woody, citrus, roasted, and alcohol. In all flower and leaf tea samples, monounsaturated (MUFAs), polyunsaturated (PUFAs), and saturated fatty acids (SFAs) were identified. A high content of omega-6 was quantified in acacia, Saint John's Wort, rose, and yarrow, while omega-3 was found in mint, Saint John's Wort, green, blueberry, and lavender samples. The flower and leaf tea samples studied could be a good dietary source of polyphenolic compounds, essential elements. In instant tea samples, a low quantity of polyphenols and major elements were identified. The physicochemical analysis demonstrated that both flower and leaf teas have high-quality properties when compared to instant tea.
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This study aimed to analyze the production of poly(3-hydroxybutyrate) (PHB) from lignocellulosic biomass through a series of steps, including microwave irradiation, ammonia delignification, enzymatic hydrolysis, and fermentation, using the Bacillus megaterium ATCC 14581 strain. The lignocellulosic biomass was first pretreated using microwave irradiation at different temperatures (180, 200, and 220 °C) for 10, 20, and 30 min. The optimal pretreatment conditions were determined using the central composite design (CCD) and the response surface methodology (RSM). In the second step, the pretreated biomass was subjected to ammonia delignification, followed by enzymatic hydrolysis. The yield obtained for the pretreated and enzymatically hydrolyzed biomass was lower (70.2%) compared to the pretreated, delignified, and enzymatically hydrolyzed biomass (91.4%). These hydrolysates were used as carbon substrates for the synthesis of PHB using Bacillus megaterium ATCC 14581 in batch cultures. Various analytical methods were employed, namely nuclear magnetic resonance (1H-NMR and13C-NMR), electrospray ionization mass spectrometry (EI-MS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA), to identify and characterize the extracted PHB. The XRD analysis confirmed the partially crystalline nature of PHB.
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This study aimed to investigate the ways in which the thermal behavior, composition, and volatile compound contents of roasted coffee beans depend on variety and roasting intensity. The thermal analysis revealed various transformations in coffee composition, namely, drying, water loss, and decomposition of polysaccharides, lipids, amino acids, and proteins. The results showed that volatile compounds are released differently in coffee depending on coffee type and degree of roasting. The most abundant volatile compounds present in the samples were 2-butanone, furan, 2-methylfuran, methyl formate, 2.3-pentanedione, methylpyrazine, acetic acid, furfural, 5-methyl furfural, and 2-furanmethanol. The total polyphenol contents ranged between 13.3 and 18.9 g gallic acid/kg, being slightly higher in Robusta than in Arabica varieties and in more intensely roasted beans compared to medium-roasted beans. The Robusta variety has higher mineral contents than Arabica, and the contents of most minerals (K, Ca, Mg, Fe, Cu, P, N, and S) increased with roasting intensity. Discrimination between coffee varieties and roasting intensities is possible based on mineral and polyphenol contents.
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In this study the adsorption and photodegradation capabilities of modified multi-walled carbon nanotubes (MWCNTs), using tartrazine as a model pollutant, is demonstrated. MWCNT-COOH/Fe3O4 and MWCNT-COOH/Fe3O4/NiO nanocomposites were prepared by precipitation of metal oxides in the presence of MWCNTs. Their properties were examined by X-ray diffraction in powder (XRD), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, synchrotron-based Scanning PhotoElectron Microscopy (SPEM), and Brunauer-Emmett-Teller (BET) analysis. It was found that the optimal adsorption conditions were pH 4 for MWCNT-COOH/Fe3O4 and pH 3 for MWCNT-COOH/Fe3O4/NiO, temperature 25 °C, adsorbent dose 1 g L-1, initial concentration of tartrazine 5 mg L-1 for MWCNT-COOH/Fe3O4 and 10 mg L-1 for MWCNT-COOH/Fe3O4/NiO and contact time 5 min for MWCNT-COOH/Fe3O4/NiO and 15 min for MWCNT-COOH/Fe3O4. Moreover, the predominant degradation process was elucidated simultaneously, with and without simulated sunlight irradiation, using thermal lens spectrometry (TLS) and UV-Vis absorption spectrophotometry. The results indicated the prevalence of the photodegradation mechanism over adsorption from the beginning of the degradation process.
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BACKGROUND: The aim of this study was to explore the rare variants in a cohort of Romanian index cases with hypertrophic cardiomyopathy (HCM). METHODS: Forty-five unrelated probands with HCM were screened by targeted next generation sequencing (NGS) of 47 core and emerging genes connected with HCM. RESULTS: We identified 95 variants with allele frequency < 0.1% in population databases. MYBPC3 and TTN had the largest number of rare variants (17 variants each). A definite genetic etiology was found in 6 probands (13.3%), while inconclusive results due to either known or novel variants were established in 31 cases (68.9%). All disease-causing variants were detected in sarcomeric genes (MYBPC3 and MYH7 with two cases each, and one case in TNNI3 and TPM1 respectively). Multiple variants were detected in 27 subjects (60%), but no proband carried more than one causal variant. Of note, almost half of the rare variants were novel. CONCLUSIONS: Herein we reported for the first time the rare variants identified in core and putative genes associated with HCM in a cohort of Romanian unrelated adult patients. The clinical significance of most detected variants is yet to be established, additional studies based on segregation analysis being required for definite classification.
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BACKGROUND: The streptokinase (SK) regimen (1.5 MU/60 min) has remained unchanged in the ST-segment elevation acute myocardial infarction (STEMI) for the last 20 years. AIM: To compare the efficacy of an accelerated SK (ASK) regimen combined with enoxaparin (Enox) or heparin (UFH) with the standard SK and UFH combination in STEMI. METHODS: 633 consecutive patients, aged 21-74 years, admitted within 6 hours after the onset of STEMI, were divided in three groups: (1) ASKEnox (n=165): Enox 40 mg. i.v. followed by SK 1.5 MU over 20 min, either as a full dose or a double infusion of 0.75 MU over 10 min. separated by 50 min. After SK infusion, Enox was administered 1 mg/kg s.c. every 12 hours for 5-7 days; (2) ASKUFH (n=264): the same ASK regimen plus UFH 1,000 IU/h for 48-72 hours, (3) SSKUFH (n=204): SK 1.5 MU/60 min. plus UFH 1,000 IU/h for 48-72 hours. All patients received aspirin. Three coronary reperfusion (CR) criteria were used: 1. rapid cessation of chest pain; 2. rapid reduction of ST-segment elevation by more than 50% of the initial value; 3. rapid increase in plasma CK and CK-MB with a peak in the first 12 hours. RESULTS: The rates of CR in the ASKEnox (77.6%) and the ASKUFH (73.5%) groups were similar but both were significantly higher than that observed in the SSKUFH group (62.2%) (p=0.002 and 0.013, respectively). The 30-day mortality rates were similar in the ASKEnox (6.06%) and the ASKUFH (6.81%) groups but both were significantly lower than in the SSKUFH group (12.74%) (p=0.048 and 0.044, respectively). SK-induced hypotension was more frequent in the ASKEnox (39.4%) and ASKUFH (38.3%) groups compared with the SSKUFH group (20.6%) (p<0.0001), but it was transient and well tolerated. Haemorrhagic stroke occurred in two patients from the SSKUFH and one patient from the ASKUFH groups. CONCLUSIONS: ASKEnox and ASKUFH regimens are safe and result in a significantly higher rate of CR and a lower in-hospital mortality compared with the traditional SSKUFH regimen.
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Enoxaparina/administración & dosificación , Fibrinolíticos/administración & dosificación , Sistema de Conducción Cardíaco/fisiopatología , Infarto del Miocardio/tratamiento farmacológico , Estreptoquinasa/administración & dosificación , Terapia Trombolítica/métodos , Adulto , Anciano , Esquema de Medicación , Electrocardiografía , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: The classical streptokinase regimen (1.5 M.U. over 60 min) may be too slow in patients with ST-elevation myocardial infarction (STEMI). OBJECTIVE: To compare the efficacy and safety of four streptokinase regimens in STEMI patients. METHODS: 1880 consecutive patients admitted within 6 h of STEMI onset were allocated one of the following four streptokinase regimens: 1.5 M.U. over 60 min (n=517); 1.5 M.U./30 min (n=355); 1.5 M.U./20 min (n=507); 0.75 M.U./10 min, repeated or not after 50 min if no electrocardiographic criteria of reperfusion (n=501). RESULTS: Rates of coronary reperfusion (non-invasively detected) for SK1.5/30 (72.39%), SK1.5/20 (75.34%) and SK0.75/10 (72.85%) were similar and higher than for SK1.5/60 (64.03%, p=0.019, p<0.0001, and p=0.006, respectively). In-hospital mortality was significantly lower for SK1.5/20 (7.10%) and SK0.75/10 (7.38%) and at the limit of significance for SK1.5/30 (7.60%) compared with SK1.5/60 (11.60%, p<0.0001, 0.006, and 0.053, respectively). Intracerebral haemorrhage and other major bleeding had similar incidence in the four groups. CONCLUSIONS: Compared to the classical 1.5 M.U. over 60 min streptokinase regimen, significantly higher rates of coronary reperfusion and lower in-hospital mortality can be obtained by infusing the same dose over only 20 min, or either one or two half doses over only 10 min, without risk increase.
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Infarto del Miocardio/tratamiento farmacológico , Sistema de Registros , Estreptoquinasa/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Infarto del Miocardio/fisiopatología , Reperfusión Miocárdica/métodos , Rumanía , Factores de TiempoAsunto(s)
Síndrome de Brugada/diagnóstico , Inhalación/fisiología , Adulto , Electrocardiografía , Humanos , MasculinoRESUMEN
OBJECTIVE: To compare a new streptokinase regimen combined with either enoxaparin or unfractionated heparin (UFH) and the traditional streptokinase regimen combined with UFH in patients with acute myocardial infarction (AMI). METHODS: 412 patients (<75 years), hospitalized within 6 hours of the onset of chest pain, were allocated thrombolytic therapy by the treating physician: streptokinase 0.75 MU/10 minutes, repeated if no coronary reperfusion after one dose, plus enoxaparin 40 mg intravenously followed by 1 mg/kg bodyweight subcutaneously at 12-hour intervals for 5-7 days (n = 102); the same streptokinase regimen plus UFH 1000 IU/60 minutes intravenously for 48-72 hours ( n = 106); or streptokinase 1.5 MU/60 minutes plus the same UFH regimen (n = 204). All patients received 250-325 mg aspirin/day. Coronary reperfusion rates, 30-day mortality and hemorrhagic complications were recorded. RESULTS: Coronary reperfusion rates with 0.75 streptokinase + enoxaparin (78.4%) and 0.75 streptokinase + UFH (74.5%) were significantly higher than those with 1.5 streptokinase + UFH (62.2%), but there was no significant difference between the groups receiving the new regimen. Overall 30-day mortality (6.3%) was significantly lower than with 1.5 streptokinase + UFH (12.7%) ( p = 0.037). The incidence of major and minor hemorrhagic events was similar in all groups. CONCLUSIONS: The accelerated streptokinase regimen was well tolerated and resulted in a significantly higher coronary reperfusion rate and significantly lower mortality compared with the traditional regimen. The 0.75 streptokinase + enoxaparin combination was at least as efficacious as the 0.75 streptokinase + UFH combination and is preferred because of its ease of administration and predictable anticoagulant effect.
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Enoxaparina/administración & dosificación , Infarto del Miocardio/tratamiento farmacológico , Estreptoquinasa/administración & dosificación , Anciano , Quimioterapia Combinada , Femenino , Heparina/administración & dosificación , Humanos , Hipotensión/inducido químicamente , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Reperfusión Miocárdica/métodos , Estreptoquinasa/efectos adversos , Tasa de SupervivenciaRESUMEN
UNLABELLED: The Streptokinase (SK) regimen (1.5 MU/60 minutes) has remained unchanged for the past 20 years in patients with ST-segment elevation acute myocardial infarction (STEMI) due to fear of hypotension (a specific effect of this thrombolytic agent) and of hemorrhagic complications. OBJECTIVE: To evaluate the influence of the Streptokinase-induced hypotension (SK-hTA) on the rate of coronary reperfusion (CR), incidence of cardiogenic shock (CS), 30-day mortality and incidence of stroke in patients (pts.) with STEMI. The SK-hTA was defined as decrease of the systolic blood pressure with at least 20% within the first 20 min. after the start of the SK infusion. METHODS: A group of 837 pts. (age 20-90) with thrombolytic treatment, with three "accelerated" SK regimens within the first 6 hours after the onset of STEMI and enrolled in the Romanian open, prospective, non-randomised study for accelerated SK in STEMI (ASK-ROMANIA) have been included. The SK regimens consisted in infusing of the standard dose of 1.5 M.U. either in 30 min. (regimen SK1.5/30, 173 pts).) or in 20 min. (regimen SK1.5/20, 377 pts.) or of the half dose (0.75 M.U.) in 10 min. followed by a new infusion of 0.75 M.U. after 50 min. only if no bed-side signs of CR have been recorded (regimen SK 0.75/10, 287 pts.). The speed of the SK infusion was maintained in all pts. experiencing SK-hTA. All pts. received aspirin and heparin or enoxaparin if not contraindicated. Three noninvasive CR criteria have been used: 1. Rapid cessation of the chest pain. 2. Rapid decrease of the ST segment elevation by more than 50% of the initial value. 3. Rapid increase of the CK and CK-MB with a peak within the first 12 hrs. RESULTS: SK-hTA appeared in 372 pts. (44.55%) at 9+/-5 min after the start of the SK infusion. In this subgroup the rate of CR was 74.46%, non-significantly higher than the one of 68.81% registered in pts. without SK-hTA (p=0.071). SK-hTA disappeared in all patients after 16+/-6 minutes without a specific therapy. Fourteen pts. with SK-hTA (3.76%) and 16 pts. without SK-hTA (3.44%) developed CS after thrombolysis ( non-significant difference). The global in-hospital mortality was 10.21% in pts. with SK-hTA and 9.89% in pts. without this side effect (non-significant difference). The incidences of hemorrhagic and ischemic strokes were 0.26% (1 patient) respectively 0.52% (2 pts.) in the SK-hTA subgroup and 0.43% (2 pts.) respectively 0.64% (3 pts.) in the subgroup without SK-hTA. CONCLUSIONS: 1. Despite a very high incidence (44.55%) the SK-hTA has not a detrimental effect in pts. treated with accelerated SK regimens for STEMI. 2. Streptokinase can be rapidly administered without an increased risk.
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Fibrinolíticos/uso terapéutico , Heparina/uso terapéutico , Hipotensión/inducido químicamente , Infarto del Miocardio/tratamiento farmacológico , Estreptoquinasa/uso terapéutico , Terapia Trombolítica , Adulto , Anciano , Anciano de 80 o más Años , Aspirina/uso terapéutico , Ensayos Clínicos como Asunto , Quimioterapia Combinada , Femenino , Fibrinolíticos/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Estudios Prospectivos , Rumanía , Choque Cardiogénico/inducido químicamente , Estreptoquinasa/efectos adversos , Accidente Cerebrovascular/inducido químicamente , Terapia Trombolítica/efectos adversos , Terapia Trombolítica/métodosRESUMEN
OBJECTIVE: To compare the efficacy and safety of an accelerated streptokinase regimen (double bolus of 0.75 MU in 10 min) in combination with enoxaparin (SK0.75Enox regimen) with the one of the front loaded alteplase (t-PA 100 mg/90 min) plus heparin (the t-PAHep regimen) in patients (pts.) with ST-segment elevation acute myocardial infarction (STAMI). METHODS: One hundred seventy three pts. (age 18-74) treated within the first 6 hrs. after the onset of STAMI with the above two mentioned thrombolytic regimens were included. 1. The group SK0.75Enox (102 pts.) received an i.v. bolus of 40 mg Enox followed by 0.75 MU SK in 10 min. A second bolus of 0.75 MU SK would be administrated only if no bed-side signs of coronary reperfusion (CR) were detected within the next 50 min. After thrombolysis Enox was administered 1 mg/kg bodyweight every 12 hrs. for 5-7 days. 2. The group t-PAHep (71 pts.) received 15 mg oft-PA in bolus followed by 50 mg in 30 min and 35 mg within the next 60 min; t-PA was followed by heparin 1000 u/hour for the next 48-72 hours. All the patients received aspirin. Three noninvasive CR criteria were used: 1. Rapid cesation of the chest pain. 2. Rapid decrease of the ST segment elevation by more than 50% from the initial value. 3. Rapid increase of the CK and CK-MB with a peak within the first 12 hrs. RESULTS: Two patients (2.85%) from the t-PAHep group had non-fatal stroke (one haemorrhagic, one ischemic). No other major haemoragical events were registered in both groups. During the thrombolytic infusion hypotension appeared more frequently in the SK0.75Enox group (31.4%) than in the t-PAHep one (8.5%) (p>0.0001) but without any consequence regarding the patients' outcome. The ratio of CR was 78.4% in the SK0.75Enox group and 70.4% in the t-PAHep one (p = 0.308). In-hospital reocclusion appeared in 4 pts. from the t-PAHep group (5.7%) but in none in the SK0.75Enox one. Six pts. (5.9%) from the SK0.75Enox group and 5 pts. from the t-PA one (7.04%) died within the first 30 days after the onset of STAMI (p = 0.993). CONCLUSIONS: The combination SK0.75Enox is at least as safe and efficacious as the t-PAHep one.