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Carboxymethylated derivatives of pullulan (PU) were synthesized and evaluated as coating for the postharvest preservation of blueberries. Carboxymethylpullulan was obtained by etherification reaction with the substitution degrees of 0.52, 0.34, and 0.26 for CMP1, CMP2, and CMP3 respectively. Infrared spectroscopy and nuclear magnetic resonance results showed characteristic signals of the carbonyl group belonging to the carboxymethyl group. Thermal analysis showed that CMP1, CMP2, and CMP3 derivatives presented thermal stability values of 209.91 C, 214.73 C, and 225.52 °C, respectively, and were lower with respect to PU with Td of 238.84 °C. Furthermore, an increase in the glass transition temperature due to carboxymethylation was determined. The chemical modification decreased the contact angle with respect to PU (71.34°) with values for CMP1, CMP2, and CMP3 of 39.89°, 53.72° and 60.61°, respectively. The carboxymethylation also increased the water vapor permeability and mechanical properties of the films. In addition, it was found that the CMP molecules affected the optical properties. The application of CMP-based coatings reduced the mass loss and ripening rate of blueberries compared to native pullulan, therefore, packaging from CMP molecules could be used as a coating capable of delaying ripening and extending the shelf life of fruits.

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This study evaluated lactic acid production through batch fermentation in a bioreactor with Thermoanaerobacter sp. strain USBA-018 and a chemically defined culture medium and with hydrolyzed pressed extract of Aloe vera peel (AHE). The strain USBA-018 fermented various sugars, but its primary end-product was L-lactic acid. Factors which influenced L- lactic acid production were pH, addition of yeast extract (YE) and manganese chloride. Under the most favorable growing conditions for the production of lactic acid, yield (Yp/s) increased from 0.66 to 0.96 g/g with a productivity (Qp) of 0.62 g.l-1.h and a maximum lactic acid concentration of 178 mM at 26 hours of fermentation. When AHE was used, 93.3 mM, or 0.175 g.l-1.h, was obtained. These results show the potential for transformation of sugars that strain USBA-018 offers, but additional studies are needed to find out if different strategies using AHE as carbon source can produce large enough quantities of lactic acid to allow AHE to become a low-cost alternative substrate.

Este estudio evaluó la producción de ácido láctico de la cepa de Thermoanaerobacter sp. USBA-018 en un biorreactor de fermentación por lotes, utilizando como medios de cultivo una formulación químicamente definida y un extracto prensado e hidrolizado de cáscara de Aloe vera (AHE). La cepa USBA-018 fermentó varios azúcares, pero su principal producto final fue L-ácido láctico. Los factores que influyeron en la producción de L-ácido láctico fueron pH, adición de extracto de levadura (YE) y de cloruro de manganeso. Bajo las condiciones más favorables de crecimiento para la producción de ácido láctico el rendimiento (Yp/s) aumentó de 0.66 a 0.96 g/g, con una productividad (Qp) de 0.62 g.l-1.h y una máxima concentración de ácido láctico de 178 mM a las 26 horas de fermentación. Cuando se usó AHE, se obtuvieron 93.3 mM, o 0.175 g.l-1.h. Estos resultados muestran el potencial de transformación de azúcares que ofrece la cepa USBA-018, pero se requieren estudios adicionales para determinar si diferentes estrategias de uso de AHE como fuente de carbono producen cantidades suficientemente grandes de ácido láctico como para permitir que el AHE se convierta en un sustrato alternativo de bajo costo.

Este estudo avaliou a produção de ácido lático por meio de fermentação descontinua em um biorreator com Thermoanaerobacter sp. cepa USBA-018 e um meio de cultura químicamente definido e com extrato hidrolisado de casca de Aloe vera (AHE). A cepa USBA-018 fermentou vários acucares, mas seu produto final primàrio foi L-ácido lático. Os fatores que influenciaram a produção de L-ácido lático foram o pH, adição de extrato de levedura (YE) e cloreto de manganès. Sob as condicoes de crescimento mais favoráveis para a produção de ácido lático, o rendimento (Yp/S) aumentou de 0,66 a 0,96 g/g com uma produtividade (Q) de 0,62 g.L4.h e um máximo de concentração de ácido lático de 178 mM em 26 horas de fermentação. Quando o AHE foi utilizado, se obteve 93,3 mM ou 0,175 g.L-1.h. Estes resultados mostram o potencial para transformação de acucares que a cepa USBA-018 oferece, entretanto estudos adicionais sáo necessários para descobrir se diferentes estrategias utilizando o AHE como fonte de carbonos podem produzir quantidades de ácido lático grandes o suficiente para permitir que AHE se converta em um substrato alternativo de baixo custo.

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Fungal symbionts that live asymptomatically inside plant tissues (endophytes) can influence plant-insect interactions. Recent work has shown that damage by leaf-cutting ants, a major Neotropical defoliator, is reduced to almost half in plants with high densities of endophytes. We investigated changes in the phenotype of leaves that could influence ants' behavior to result in the reduction of foliar damage. We produced cucumber seedlings with high and low densities of one common endophyte species, Colletotrichum tropicale. We used the leaves in bioassays and to compare chemical and physical leaf characteristics important for ants' food selection. Ants cut about one-third more area of cucumber leaves with lower densities of endophytes and removed c. 20% more paper disks impregnated with the extracts of those leaves compared with leaves and disks from plants hosting the fungus. Colletotrichum tropicale colonization did not cause detectable changes in the composition of volatile compounds, cuticular waxes, nutrients or leaf toughness. Our study shows that endophytes changed leaf chemistry and suggests that compounds with relative low volatility released after leaf wounding are a major factor influencing foraging decisions by ants when choosing between plants with low or high endophyte loads.

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OBJECTIVE: Strengthen knowledge about the pathophysiology of aortic stenosis. METHODS: Urinary levels of angiotensin-(1-7) and angiotensin II were compared between two samples: A) forty five patients with severe aortic stenosis, without systemic arterial hypertension and with normal kidney and normal left ventricular systolic function; B) control group: twenty one persons without cardiovascular disease. NULL HYPOTHESIS: there would be no difference between urinary levels. RESULTS: The average of angiotensin-(1-7) urinary concentration in severe aortic stenosis patients was 2.102 pmol/mL and 5.591 pmol/mL for the control group. The average of Ang II was 0.704 pmol/mL and 0.185 pmol/mL respectively. Using t-Student test, we determine that the difference in urinary concentration of angiotensin-(1-7) [p=0.633] and the difference of angiotensin II (p=0.631), were statistically significant. CONCLUSION: documented a statistically significant difference in urinary levels angiotensin II and angiotensin-(1-7) within the group of patients with severe aortic stenosis.

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Objetivo:Reforzar el conocimiento sobre la fisiopatología de la estenosis aórtica. Métodos: Se compararon los niveles urinarios de angiotensina II y angiotensina-(1-7) entre dos muestras: a) 45 pacientes con estenosis aórtica de importante repercusión hemodinámica, sin hipertensión arterial sistémica y con funciones renal y sistólica ventricular izquierda normales; b) grupo de control con 21 voluntarios sin patología cardiovascular. Hipótesis nula: no habría diferencia entre los niveles urinarios. Resultados:El promedio de la concentración urinaria de angiotensina-(1-7) en pacientes con estenosis aórtica fue 2.102 pmoles/mL y de 5.591 pmoles/mL para el grupo control. La media obtenida en concentración urinaria de angiotensina II fue de 0.704 pmoles/mL en los pacientes con estenosis aórtica y 0.185 pmoles/mL en el grupo control. Utilizando la prueba t de Student determinamos que la diferencia en la concentración urinaria de angiotensina-(1-7) (p = 0.633) y la diferencia en la concentración urinaria de angiotensina II (p = 0.631), fueron estadísticamente significativas. Conclusión:Se documentó una diferencia estadísticamente significativa en los niveles urinarios de angiotensina II y angiotensina-(1-7) dentro del grupo de pacientes con estenosis aórtica de importante repercusión hemodinámica.

Objective:Strengthen knowledge about the pathophysiology of aortic stenosis. Methods: Urinary levels of angiotensin-(1-7) and angiotensin II were compared between two samples: A) forty five patients with severe aortic stenosis, without systemic arterial hypertension and with normal kidney and normal left ventricular systolic function; B) control group: twenty one persons without cardiovascular disease. Null hypothesis: there would be no difference between urinary levels. Results: The average of angiotensin-(1-7) urinary concentration in severe aortic stenosis patients was 2.102 pmol/mL and 5.591 pmol/mL for the control group. The average of Ang II was 0.704 pmol/mL and 0.185 pmol/mL respectively. Using t-Student test, we determine that the difference in urinary concentration of angiotensin-(1-7) [p = 0.633] and the difference of angiotensin II (p = 0.631), were statistically significant. Conclusion:documented a statistically significant difference in urinary levels angiotensin II and angiotensin-(1-7) within the group of patients with severe aortic stenosis.

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The aortic aneurysm is part of the acute aortic syndromes (AAS). Aortic aneurysms have a weakened tunica media. Acute aneurysm expansion may herald rupture with high morbility and mortality. Five percent of AAS are diagnosed as pentetrating atherosclerotic ulcer which is an ulceration of an atherosclerotic lesion of the aorta that penetrates the internal elastic lamina and allows hematoma formation within the tunica media of the aortic wall. Endovascular treatment is an alternative to surgery and has provided an adequate rate of successful repair. There is another type of treatment which combines surgery and endovascular repair (the hybrid open-endovascular repair) which provides adequate results. The afford mention case is about a patient with a penetrating atherosclerotic ulcer. The hematoma that results from this ulcer extends and self-contains the aneurysm, with a high risk of rupture. We will also describe the aneurysm treatment options.

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The aortic aneurysm is part of the acute aortic syndromes (AAS). Aortic aneurysms have a weakened tunica media. Acute aneurysm expansion may herald rupture with high morbility and mortality. Five percent of AAS are diagnosed as pentetrating atherosclerotic ulcer which is an ulceration of an atherosclerotic lesion of the aorta that penetrates the internal elastic lamina and allows hematoma formation within the tunica media of the aortic wall. Endovascular treatment is an alternative to surgery and has provided an adequate rate of successful repair. There is another type of treatment which combines surgery and endovascular repair (the hybrid open-endovascular repair) which provides adequate results. The afford mention case is about a patient with a penetrating atherosclerotic ulcer. The hematoma that results from this ulcer extends and self-contains the aneurysm, with a high risk of rupture. We will also describe the aneurysm treatment options.

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A complete ECG thoracic circle allows exploring some heart structures not explored by the conventional electrocardiogram. It provides a direct indication on the location of the damaged myocardium. In fact, posterolateral infarctions can be limited to the inferior third of the left ventricle or can cover the entire free left ventricular wall from the base up to the heart apex and can be univentricular or biventricular. On the other side, the unipolar thoracic leads and the high abdominal leads MD, ME, MI show the evolution of the signs of injury, characteristic of the acute stage of infarction, toward necrosis. We present the example of a 61-year-old man, whose ECG shows signs of subepicardial or transmural injury and of necrosis in the low precordial leads V5 and V6, as well as in the high left posterior leads V8 and V9. This fact suggests the presence of an acute extensive myocardial infarction extending from the base to the heart apex. Moreover, the moderate elevation of the RS-T segment from to V9R to V7R indicates the presence of subepicardial injury in the high posterior regions of the right ventricular wall. These electrocardiographic data were confirmed by the radioactive isotope study and, definitively, by the anatomical findings.

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The association between arterial systemic hypertension arterial coronary disease has been demonstrated by cumulated evidence of several epidemiological studies. Hypertension is an important independent risk factor for the development of coronary artery disease, vascular cerebral disease and nephropathy. Important advances exist in the knowledge of neurohumoral and hemodynamic factors that come together in the pathophysiology of the hypertension and in the development of coronary disease that allow to establish better strategies not only of treatment, but also of prevention, with the purpose of diminishing the cardiovascular mortality. The spectrum of the coronary artery disease secondary to atherosclerosis is wide and the strategies of treatment of hypertension must be adapted to each particular case. The treatment of both conditions needs of specific limits of agreement to the conditions of the patient and the form of presentation of each one of these disease.

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From beginnings of last century the hypertensive emergency was defined as the association of acutely elevation from the arterial pressure and the appearance of damage to end organ. At present is recognized the effects of the hypertensive emergency, the aspects of its patophysiology in which are included phenomenon of vasomotricity and the participation of different substances with vasoactives properties. The clinical presentation includes not only the manifestations of the increase of the arterial pressure, the end organ damage too; for this reason the hypertensive emergency needs the immediate reduction of the arterial tension to prevent the damage to specific organs. The treatment in every case will have to be individualized, with a wide knowledge of the characteristics of every medicament to obtain the best results. The diagnosis and treatment of the hypertensive emergencies needs often of the attention of its complications if they have appeared and later, of a treatment of support for the arterial hypertension.

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OHC is a disorder with a broad spectrum of morphological, functional and genetics abnormalities. The Obstruction on the Right Ventricular Outflow (OHCRV) is not expected most of the time, that's way it is not usually detected and rarely mentioned in the cardiological literature. Its clinical presentation may include basically systemic venous hypertension symptoms that come with the hypertrophic cardyomiopathy manifestations. The manifestations of an apparent Right Ventricular Hypertrophic (RVH) in the ECG are probably due to the huge septal vector that activates the septum with a major thickness. The clinical confirmation of the obstruction on the OHCRV produced by a considerable asymmetric septal hypertrophic is easily shown with bidimensional an Doppler echocardiography.

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From beginnings of last century the hypertensive emergency was defined as the association of acutely elevation from the arterial pressure and the appearance of damage to end organ. At present is recognized the effects of the hypertensive emergency, the aspects of its patophysiology in which are included phenomenon of vasomotricity and the participation of different substances with vasoactives properties. The clinical presentation includes not only the manifestations of the increase of the arterial pressure, the end organ damage too; for this reason the hypertensive emergency needs the immediate reduction of the arterial tension to prevent the damage to specific organs. The treatment in every case will have to be individualized, with a wide knowledge of the characteristics of every medicament to obtain the best results. The diagnosis and treatment of the hypertensive emergencies needs often of the attention of its complications if they have appeared and later, of a treatment of support for the arterial hypertension.

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The association between arterial systemic hypertension arterial coronary disease has been demonstrated by cumulated evidence of several epidemiological studies. Hypertension is an important independent risk factor for the development of coronary artery disease, vascular cerebral disease and nephropathy. Important advances exist in the knowledge of neurohumoral and hemodynamic factors that come together in the pathophysiology of the hypertension and in the development of coronary disease that allow to establish better strategies not only of treatment, but also of prevention, with the purpose of diminishing the cardiovascular mortality. The spectrum of the coronary artery disease secondary to atherosclerosis is wide and the strategies of treatment of hypertension must be adapted to each particular case. The treatment of both conditions needs of specific limits of agreement to the conditions of the patient and the form of presentation of each one of these disease.

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OHC is a disorder with a broad spectrum of morphological, functional and genetics abnormalities. The Obstruction on the Right Ventricular Outflow (OHCRV) is not expected most of the time, that's way it is not usually detected and rarely mentioned in the cardiological literature. Its clinical presentation may include basically systemic venous hypertension symptoms that come with the hypertrophic cardyomiopathy manifestations. The manifestations of an apparent Right Ventricular Hypertrophic (RVH) in the ECG are probably due to the huge septal vector that activates the septum with a major thickness. The clinical confirmation of the obstruction on the OHCRV produced by a considerable asymmetric septal hypertrophic is easily shown with bidimensional an Doppler echocardiography.

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The four major components present in scent gland extracts of the male Costa Rica longwing butterflies Heliconius cydno and Heliconius pachinus were identified as 12- and 14-membered macrolides containing a C(18)-carbon skeleton. By use of micro-reactions and spectrometric examinations, structural proposals were made and subsequently proven by synthesis, using ring-closing-metathesis as the key steps. These macrolides, (9Z,11E,13S)-octadeca-9,11-dien-13-olide (5, S-coriolide), (9Z,11E,13S,15Z)-octadeca-9,11,15-trien-13-olide (6), (9Z,13S)-octadec-9-en-13-olide (13), and (9Z,11S)-octadec-9-en-11-olide (25), are biosynthetically obviously derived from oleic, linoleic, and linolenic acids. Their absolute configurations were determined by gas chromatographic investigations on chiral phases, showing all to possess (S)-configuration.

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OBJECTIVE: Based on a National Re-survey on Hypertension (HTA) and other cardiovascular risk factors performed in Mexico during 2003 and 2004 in the adult population with HTA, as identified in the 2000 National Survey of Health, this study was planed to determine: 1) morbidity and mortality rates; 2) the incidence and interrelation with other risk factors, such as overweight, obesity, dyslipidemia, nephropathy and diabetes; 3) the main risk factors associated to HTA involved in its complications, need for hospitalization and number of days; and, 4) the degree of therapeutical adhesion and the type of antihypertensive drugs used. METHODS: The survey was of type III using the step by step method described by WHO. Sampling was weighed a priori taking into account a national prevalence average of HTA of 30.05% and its corresponding rate for each federal state. Permissible maximum error in the estimation = 0.28. Effect of design = 4.5; and, Rate of awaited answer (0.70). RESULTS: From the initial 14,567 interviewed patients, 1,165 (8%) subjects were considered non-hypertensive or false positives at the 2000 survey. From the 13,402 remaining patients, 335 died during the first 2 years of pursuit, which implies an annual mortality of approximately 1.15% in the hypertensive population. Thus, 13,067 survivors were subjected to the final analysis. The mean age at the re-survey was 45.6 +/- 12.6; 40.5% were men (n = 5,295). There was a statistically significant difference in height, but not in weight between both genders. The control HTA was raised 14.6% in the year 2000 and 19.2% in 2004. The prevalence of diabetes was duplicated from 16% to 30% (< .001). Fifty four percent of the whole population required hospitalization at least once during the period of study. The rates of overweight, obesity, and dyslipidemia rose significantly (p < 0.05) independently from age, federal state, and gender. CONCLUSION: RENAHTA shows the impact of hypertension on the morbidity and mortality during the 3.1 +/- 1.5 years of follow-up in Mexico. It alerts us on the need to reinforce the strategies of attention and prevention of this crucial risk factor and of screening the dynamic nonlinear interaction between the main cardiovascular risk factors in Mexico. New hypotheses are proposed for the metabolic syndrome.

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Propósito: A través de una Re-encuesta Nacional sobre Hipertensión Arterial Sistémica (HTAS) y Factores de Riesgo Cardiovascular, en población adulta con HTAS identificada en encuestas nacionales de salud del año 2000; Determinar: 1) Las tasas de morbilidad y mortalidad. 2) La incidencia e interrelación en el tiempo con otros factores de riesgo, tales como Obesidad, Dislipidemia, Diabetes y Tabaquismo. 3) Los principales factores de riesgo asociados a HTAS que influencian la aparición de complicaciones, necesidad y numero de días de hospitalización. 4) El grado de adherencia y tipo de medicación usada por el paciente hipertenso. Métodos: La Re-encuesta Nacional de Hipertensión (RENAHTA) fue realizada en el periodo 2003-2004. La encuesta es tipo III del método paso a paso descrito por la OMS. La población estudiada correspondió en su mayoría (73%) a individuos detectados en encuestas nacionales previas. El muestreo fue ponderado a priori tomando en cuenta una prevalencia nacional promedio de HTAS de 30.05% y su correspondiente para cada estado de la República. Error máximo permisible en la estimación = 0.28, Efecto de diseño = 4.5; y, Tasa de respuesta esperada (0.70). Resultados: De 14 567 como muestra inicial, 1165 (8%) sujetos fueron considerados como no hipertensos o falsos positivos en el año 2000. De los 13,402 pacientes restantes se informaron 335 muertes ocurridas en los primeros 2 años de seguimiento (2000-2002), lo que implicó una mortalidad anual de ˜1.15% en la población hipertensa. Así, 13,067 sobrevivientes, fueron sujetos a análisis. La edad al momento de la re-encuesta fue 45.6 ± 12.6. El (40.5%) fueron hombres (n=5,295), hubo diferencia estadísticamente significativa en la talla, pero no en el peso entre ambos géneros. El control de la HTAS subió de 14.6% en el 2000 a 19.2% en el 2004. Se duplicó la cifra de diabéticos de 16% a 30% (p < .001). El 54% de la población estudiada requirió de hospitalización al menos ...

Objective: Based on a National Re-survey on Hypertension (HTA) and other cardiovascular risk factors performed in Mexico during 2003 and 2004 in the adult population with HTA, as identified in the 2000 National Survey of Health, this study was planed to determine: 1) morbidity and mortality rates; 2) the incidence and interrelation with other risk factors, such as overweight, obesity, dyslipidemia, nephropathy and diabetes; 3) the main risk factors associated to HTA involved in its complications, need for hospitalization and number of days; and, 4) the degree of therapeutical adhesion and the type of antihypertensive drugs used. Methods: The survey was of type III using the step by step method described by WHO. Sampling was weighed a priori taking into account a national prevalence average of HTA of 30.05% and its corresponding rate for each federal state. Permissible maximum error in the estimation = 0.28. Effect of design = 4.5; and, Rate of awaited answer (0.70). Results: From the initial 14,567 interviewed patients, 1,165 (8%) subjects were considered non-hypertensive or false positives at the 2000 survey. From the 13,402 remaining patients, 335 died during the first 2 years of pursuit, which implies an annual mortality of ˜1.15% in the hypertensive population. Thus, 13,067 survivors were subjected to the final analysis. The mean age at the re-survey was 45.6 ± 12.6; 40.5% were men (n = 5,295). There was a statistically significant difference in height, but not in weight between both genders. The control HTAwas raised 14.6% in the year 2000 and 19.2% in 2004. The prevalence of diabetes was duplicated from 16% to 30% (< .001). Fifty four percent of the whole population required hospitalization at least once during the period of study. The rates of overweight, obesity, and dyslipidemia rose significantly (p < 0.05) independently from age, federal state, and gender. Conclusion: RENAHTA shows the impact of hypertension on the morbidity and mortality during the 3.1 ± 1.5 years of follow-up in Mexico. It alerts us on the need to reinforce the strategies of attention and prevention of this crucial risk factor and of screening the dynamic nonlinear interaction between the main cardiovascular risk factors in Mexico. New hypotheses are proposed forthe metabolic syndrome.

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