Sexually transmitted infections in Spain: Current status.

Sexually Transmitted Infections (STI) are a major public health problem. The problems inherent to their diagnosis, treatment and prevention have to do not only with their nature, but also with organizational issues and overlapping competencies of the different health authorities in Spain. The real situation of STI in Spain, at present, is poorly known. For this reason, the Scientific Committee on COVID and Emerging Pathogens of the Illustrious Official College of Physicians of Madrid (ICOMEM) has formulated a series of questions on this subject which were distributed, not only among the members of the Committee, but also among experts outside it. The central health authorities provide very high and increasing figures for gonococcal infection, syphilis, Chlamydia trachomatis infection and lymphogranuloma venereum (LGV). Both HIV infection and Monkeypox are two important STI caused by viruses in our environment, to which it should be added, mainly, Herpes simplex virus (HSV) and Human papillomavirus (HPV) infections. Emerging microorganisms such as Mycoplasma genitalium pose not only pathogenic challenges but also therapeutic problems, as in the case of N. gonohrroeae. The pathways that patients with suspected STI follow until they are adequately diagnosed and treated are not well known in Spain. Experts understand that this problem is fundamentally managed in public health institutions, and that Primary Care and Hospital Emergency Services, together with some institutions that deal monographically with this problem, are the recipients of most of these patients. One of the most serious difficulties of STI lies in the availability of the microbiological tests necessary for their diagnosis, particularly in this era of outsourcing of microbiology services. Added to this is the increased cost of implementing the latest generation of molecular techniques and the difficulties of transporting samples. It is clear that STI are not diseases to which the entire population is equally exposed and it is necessary to have a better knowledge of the risk groups where to focus the necessary interventions adapted to their characteristics. It should not be forgotten that STI are also a problem in the pediatric age group and that their presence can be a marker of sexual abuse with all that this implies in terms of health care and medicolegal activity. Finally, STI are infections that are associated with a high cost of care for which we have very little information. The possibility of expanding the automatic performance of laboratory tests for STI surveillance through laboratory routines is encountering ethical and legal problems that are not always easy to solve. Spain has created a ministerial area of specific attention to STI and there are plans to improve the diagnosis, treatment and prevention of these problems, but we still lack the necessary evidence on their impact. We cannot forget that these are diseases that transcend the individual and constitute a Public Health problem.

Frequency, virulence factors and antifungal susceptibility of Candida parapsilosis species complex isolated from patients with candidemia in the central region of Argentina.

PURPOSE: Our objectives were to report species distribution and survival of patients with candidemia in Argentina's central region and to establish the prevalence of C.parapsilosis sensu lato species, their virulence factors and their antifungal susceptibility profiles. METHODS: Yeasts isolated from bloodstream infections in Córdoba (Argentina) (n=35) were molecularly identified. The production of lipase and acid aspartic protease (Sap), the adhesion capacity, and the isolates' ability to form biofilm were evaluated. The in vitro activity of 7 antifungal drugs was evaluated (CLSIdocument M27-4thed). RESULTS: C. albicans was the most prevalent species (48.57%) followed by C. parapsilosis sensu lato (28.57%). The 30-day survival rate for C. albicans candidemia was slightly lower than non-albicans blood infections (50.00% vs. 57.90%). C. parapsilosis sensu stricto and C. orthopsilosis account for 60% and 40% of the cryptic species. Sap production and biofilm formation capacity were higher in C. parapsilosis sensu strico than in C.orthopsilosis. All the strains were susceptible to caspofungin (CAS), anidulafungin (AFG), amphotericin B (AMB), posaconazole (POS) and voriconazole (VRC). Azoles were the most potent agent against C. parapsilosis sensu lato followed by echinocandins and AMB. There were no differences between MICs for fluconazole, VRC, POS and AMB. Contrarily, C. parapsilosis sensu stricto strains showed lower MIC than C. orthopsilopsis isolates for itraconazole and higher MIC values for echinocandins (P<0.01). CONCLUSIONS: We report a high frequency of isolation of C.orthopsilosis in candidemia patients of central region. Data on the prevalence, virulence capability and antifungal susceptibility of C. parapsilosis complex provide new epidemiological information about these cryptic species in Argentina.

Trastornos temporomandibulares en la infancia: bruxismo de sueño y compromiso de atm en artritis idiopática juvenil / Temporomandibular disorders in childhood: sleep bruxism and temporomandibular joint involvement in juvenile idiopathic arthritis

Los trastornos temporomandibulares (TTM) corresponden a un grupo de condiciones musculoesqueletales y neruromusculares que involucran las articulaciones temporomandibulares (ATM), los músculos masticatorios y todos los tejidos asociados. La etiología de los TTM es considerada multifactorial, siendo el bruxismo de sueño (BS) uno de muchos factores asociados con TTM dolorosos. Tanto los TTM como el BS se presentan en adultos y niños y actualmente es sabido que la etiopatogenia de ambos no difiere de acuerdo a la edad. Las ATM son articulaciones sinoviales que pueden verse afectadas por diversos TTM o por condiciones sistémicas como la artritis idiopática juvenil (AIJ). La ATM está involucrada en un 40% de los pacientes con AIJ, siendo subestimada debido a que clínica-mente se manifiesta con poco dolor. En el presente artículo se revisarán los conceptos de TTM y BS en niños, así como también la manifestación de la AIJ en el territorio orofacial, entregando una aproximación de su etiopatogenia, identificación y manejo.

Temporomandibular disorders (TMD) encompass a group of musculoskeletal and neuromuscular conditions that involve the temporomandibular joints (TMJ), the masticatory muscles, and all associated tissues. TMD's etiology is considered to be mul-tifactorial, were sleep bruxism (SB) is one of many causes of painful TMD. TMD and SB can present in adults and children and the etiology does not differ regarding age.TMJ are synovial joints that can be affected by many TMD as well as systemic conditions such as juvenile idiopathic arthritis (JIA). TMJ are involved in 40% of patients with JIA, which is usually underestimated because of its painless presentation.This article will review the concepts of TMD and SB in children, as well as JIA presentation in the orofacial region.

Effect of cholesterol content on the structural and dynamic membrane properties of DMPC/DSPC large unilamellar bilayers.

In this study, we report the effect of cholesterol content on the dynamic and structural properties of a dimyristoyl-phosphatidylcholine and distearoyl-phosphatidylcholine mixture in large unilamellar vesicles. The range of cholesterol concentrations studied varied around approximately 33.3mol%, where it has been postulated that an abrupt change in bilayer organization occurs. Steady-state fluorescence measurements demonstrated a typical behavior; at low temperatures in the main phase transition, the cholesterol concentration did not affect the gel phase, but at 37.5°C (phase coexistence) and in the liquid crystalline phase, the presence of cholesterol produced an increase in the fluorescence anisotropy of DPH and the generalized polarization of Laurdan. The greater effect was observed in the liquid crystalline phase, in which the bilayer became a mixture of fluid-like and liquid-ordered phases. The results obtained at approximately 33.3mol% of Cholesterol demonstrated that the Generalized Polarization of Laurdan, the DPH lifetime, the limiting anisotropy and the rotational correlation time, as well as the fluorescence quenching of DPH by TEMPO, are at maxima, while the fluorescence intensity of dehydroergosterol and the lipid solubility in TritonX-100 are at minima. These results correlate well with the hypothesis of domain segregation in the DMPC/DSPC/Cholesterol LUV system. In this context, we postulate that at 33.3mol% of Cho, the proportion of ordered domains reaches a maximum.

Oclusión terapéutica: desde las escuelas de oclusión a la odontología basada en evidencia / Therapeutic occlusion: from occlusal schools of thought to evidence-based dentistry

Tanto en la práctica clínica como en la academia, siempre está presente la interrogante de cuál es la mejor posición mandibular para organizar una oclusión terapéutica y satisfacer los requerimientos estéticos y funcionales de los pacientes. Esta pregunta se podría responder desde la perspectiva de las diferentes escuelas de oclusión, siguiendo sus técnicas y utilizando su aparatología. Sin embargo, debido a que no existe suficiente evidencia científica que sustente la superioridad de una escuela sobre la otra, es preciso hacer una revisión donde se expongan los principios en que se basan las distintas filosofías oclusales, los autores que les dieron origen, la época en que surgieron y la terminología que usaron -desde el siglo pasado hasta nuestros días-, contrastándolas con la literatura científica actual. Esta no es una tarea fácil, ya que los estudios disponibles acerca de oclusión presentan gran variabilidad en la definición operacional de los términos, haciendo difícil su comparación. Se sugiere para el futuro buscar una estandarización de las definiciones y técnicas de registro, con el objeto de generar evidencia científica confiable, conducente a la creación de protocolos de recomendación para la toma de decisiones clínicas predecibles desde el punto de vista oclusal.

Both in clinical practice and academia, there is always the question about what is the best mandibular position to organize a therapeutic occlusion that satisfies functional and aesthetic requirements from patients. This question could be answered from the point of view of different occlusion schools of thought, following their techniques and using their apparatuses. However, due to the lack of scientific evidence to support the pre-eminence of a particular school over the rest, it is necessary to go through the princip les that provide the foundations for the different occlusal philosophies: the authors who gave birth to each school of thought, the time in which they were formed and the terminology they used, from the early 20th century to present times and making a comparison with current scientific literature. This is not an easy task, given that available studies about occlusion feature a great variability in the operational definition of terms, making comparison difficult. The article suggests that it would be necessary for the future to look for a standardization of recording definitions and techniques. The aim is to generate reliable scientific evidence for the creation of protocols of recommendation for predictable decision-making from an occlusal point of view.

[Cardiovascular risk factors among university students]. / Factores de riesgo cardiovascular en estudiantes de la Universidad Austral de Chile.

BACKGROUND: Cardiovascular diseases are related to particular lifestyle patterns and the presence of cardiovascular risk factors (CVRF). AIM: To evaluate the presence of CVRF in students from Universidad Austral de Chile (UACh). MATERIAL AND METHODS: CVRF were evaluated in 385 university students aged 17 to 26years (63% women). Personal background, lifestyle, anthropometry, blood pressure, serum lipids and blood glucose were evaluated. RESULTS: Eighty eight percent of evaluated students had sedentary habits, 19% had high LDL cholesterol levels, 40% had high blood pressure, 28% smoked, 29% were overweight or obese and 20% had some stress level. CONCLUSIONS: There is a high frequency of non-healthy lifestyles and cardiovascular risk factors in this sample of university students.

Principales motivos de negativa ante la donación de órganos en población de la Región de los Ríos: marzo a mayo 2012 / Main reasons for organ donation refusals of population from Region de los Ríos: March to May 2012

INTRODUCCIÓN: La Región de los Ríos tiene uno de los pocos centros de trasplante del país. Es necesario conocer la postura de su población respecto a la donación de órganos, ya que la tasa de donantes ha bajado considerablemente. OBJETIVO: Conocer los principales motivos de negativa ante la donación de órganos, en población de la Región de los Ríos durante marzo-mayo 2012.MATERIAL Y MÉTODO: Estudio descriptivo de corte trasversal. Se aplicaron 264 encuestas a residentes de la Región de los Ríos con edades entre 18 y 65 años, sin limitaciones para responder el instrumento. Se abordaron antecedentes demográficos de los encuestados (comuna, edad, género, nivel educacional); nivel de conocimiento del sistema de donación de órganos, opinión de la familia y situación actual de registro del donante. El tamaño de muestra fue determinada a través del programa Epi info 3,2TM,con un intervalo de confianza de 95 por ciento y un error de 6 por ciento. A través del programa IBM SPSS Statistics 20, se determinó significancia estadística mediante test de x2 (p<0,05). RESULTADOS: La disposición regional a ser donantes en caso de fallecimiento es de 75 por ciento; un 33 por ciento afirma no estar dispuesto a donar para que luchen más por su vida en caso de accidente y un 31 por ciento no estaría dispuesto a donar por motivos religiosos. DISCUSIÓN: Si bien las cifras apuntan a una disposición positiva a la donación, es necesario informar en forma adecuada a la población acerca del funcionamiento del programa de trasplante, para así disminuir la negativa ante la donación de órganos.

INTRODUCTION: Region de los Ríos has one of the few transplant centers in the country; considering the decreased number of organ donors in recent years, it is necessary to understand the attitude of the population towards organ donation. OBJECTIVE: To understand the main reasons for organ donation refusals in Región de los Ríos population in March-May 2012 period. MATERIAL AND METHOD: Cross-sectional study. There were filled 264 survey forms by Región de los Ríos residents between 18 and 65 years of old, excluding people who could not answer the survey. Demographic parameters (municipality, age, gender, educational level), level of knowledge about organ donation process, family’s opinion, rate of consent to donate their own organs and those of relatives where analyzed. Sample size was determined using Epi Info 3.2TM software, using a confidence interval of 95 percent and an error of 6 percent. Statistical significance was determined via a x2 statistical test (p<0.05). The test was performed using IBM SPSS Statistics software. RESULTS: The average consent to become a donor in case of death in Región de los Ríos is 75 percent 33 percent of them, said they do not consent organ donation so that doctors would strive more for their lives in case of an accident and 31percent did not agree to organ donation because of religious beliefs. DISCUSSION: Although numbers indicate a positive attitude towards donation, it is necessary to increase population’s knowledge and understanding in transplant matters in order to reduce organ donation refusal.

Human erythrocytes and neuroblastoma cells are in vitro affected by sodium orthovanadate.

Research on biological influence of vanadium has gained major importance because it exerts potent toxic, mutagenic, and genotoxic effects on a wide variety of biological systems. However, hematological toxicity is one of the less studied effects. The lack of information on this issue prompted us to study the structural effects induced on the human erythrocyte membrane by vanadium (V). Sodium orthovanadate was incubated with intact erythrocytes, isolated unsealed human erythrocyte membranes (IUM) and molecular models of the erythrocyte membrane. The latter consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. This report presents evidence in order that orthovanadate interacted with red cell membranes as follows: a) in scanning electron microscopy (SEM) studies it was observed that morphological changes on human erythrocytes were induced; b) fluorescence spectroscopy experiments in isolated unsealed human erythrocyte membranes (IUM) showed that an increase in the molecular dynamics and/or water content at the shallow depth of the lipids glycerol backbone at concentrations as low as 50µM was produced; c) X-ray diffraction studies showed that orthovanadate 0.25-1mM range induced increasing structural perturbation to DMPE; d) somewhat similar effects were observed by differential scanning calorimetry (DSC) with the exception of the fact that DMPC pretransition was shown to be affected; and e) fluorescence spectroscopy experiments performed in DMPC large unilamellar vesicles (LUV) showed that at very low concentrations induced changes in DPH fluorescence anisotropy at 18°C. Additional experiments were performed in mice cholinergic neuroblastoma SN56 cells; a statistically significant decrease of cell viability was observed on orthovanadate in low or moderate concentrations.

Factores de riesgo cardiovascular en estudiantes de la Universidad Austral de Chile / Cardiovascular risk factors among university students

Background: Cardiovascular diseases are related to particular lifestyle patterns and the presence of cardiovascular risk factors (CVRF). Aim: To evaluate the presence of CVRF in students from Universidad Austral de Chile (UACh). Material and Methods: CVRF were evaluated in 385 university students aged 17 to 26years (63% women). Personal background, lifestyle, anthropometry, blood pressure, serum lipids and blood glucose were evaluated. Results: Eighty eight percent of evaluated students had sedentary habits, 19% had high LDL cholesterol levels, 40% had high blood pressure, 28% smoked, 29% were overweight or obese and 20% had some stress level. Conclusions: There is a high frequency of non-healthy lifestyles and cardiovascular risk factors in this sample of university students.

Factores de riesgo para el desarrollo de enfermedad renal crónica en estudiantes de medicina, Universidad Austral de Chile, 2010 / Risks factors on the development of chronic kydney disease on medical students, Universidad Austral de Chile, 2010

La Enfermedad Renal Crónica (ERC) afecta aproximadamente al 10 por ciento de la población adulta. OBJETIVO: Cuantificar factores de riesgo directos e indirectos que inciden en el desarrollo de ERC. PACIENTES Y MÉTODOS: Estudio epidemiológico analítico de corte transversal. En abril de 2010 respondieron una encuesta sobre “Factores de riesgo renal (FRR)” 164 alumnos de primer a tercer año de la carrera de Medicina de la Universidad Austral de Chile. Se consideraron factores de riesgo directo: Diabetes Mellitus (DM1), Hipertensión Arterial (HTA) y consumo de analgésicos en los encuestados y factores de riesgo indirecto: dislipidemia, sobrepeso u obesidad en los encuestados y DM2, HTA, sobrepeso u obesidad y dislipidemia en familiares de primer y segundo grado. Para el análisis de los resultados se utilizó Excel 8.0 y PASW-Statistic18. RESULTADOS: De los 164 alumnos, el 60,4 por ciento (n=99) fueron varones. Con respecto a los factores de riesgo, el 28 por ciento (n=50) se automedica al menos 1 vez a la semana algún tipo de analgésico, 32 por ciento(n=52) presentaban IMC>25 (IMC promedio en varones 24,03 y en mujeres 21,8). Del total, un 48 por ciento (n=78) posee antecedentes familiares de sobrepeso u obesidad, 52 por ciento (n=86) de HTA y 27 por ciento (n=44) DM2, existiendo una relación estadísticamente significativa (p<0.05) entre estos antecedentes y la presencia de estos mismos factores de riesgo en los encuestados. DISCUSIÓN: Un porcentaje importante del 50 por ciento de los estudiantes encuestados presenta potenciales factores de riesgo tanto directos como indirectos para desarrollar ERC.

Chronic Kidney Disease (CKD) affects approximately 10 percent of adult population. The detection of factors that could increase the risk of developing CKD in the adult life in young population, acquires special importance for the development of future interventions to anticipate this disease. OBJECTIVES: To quantify direct and indirect risk factors that could influence CKD’s development. PATIENTS AND METHODS: Analytic, cross-sectional study. On April the instrument “Factors of Renal Risk” was applied to 164 students of first to third year of Medical School, Universidad Austral de Chile, Valdivia. They were considered direct risk factors Diabetes Mellitus (DM1), High Blood Pressure (HBP) and consumption of analgesics and factors of indirect risk were considered overweight or obesity and DM2, HBP, overweight or obesity in relatives of the first and second degree. For data analysis Excel8.0 and PASW-Statistic18 were used. RESULTS: Of 164 students, 60,4 percent (n=99) was males. With regard to the factors of risk, 28 percent (n=50) consumes some analgesics at least once a week, 32 percent (n=52) was presenting IMC> 25 (average IMC in males 24,03 and in women 21,8). 48 percent (n=78) possesses familiar case history of overweight or obesity, 52 percent (n=86) of HTA and 27 percent (n=44) DM2, existing a statistically significant relation (p <0.05) between these precedents and the factors presented before for same population. DISCUSSION: A not despicable percentage of the students present potential direct and indirect risk factors to develop CKD.

New superheavy element isotopes: ²4²Pu(48Ca,5n) ²85114.

The new, neutron-deficient, superheavy element isotope ²85114 was produced in 48Ca irradiations of ²4²Pu targets at a center-of-target beam energy of 256 MeV (E*=50 MeV). The α decay of ²85114was followed by the sequential α decay of four daughter nuclides, 281Cn, 277Ds, 273Hs, and 269Sg. 265Rf was observed to decay by spontaneous fission. The measured α-decay Q values were compared with those from a macroscopic-microscopic nuclear mass model to give insight into superheavy element shell effects. The²4²Pu (48Ca,5n²)²85114 cross section was 0.6(-0.5)+0.9 pb.

Mn2+ exerts stronger structural effects than the Mn-citrate complex on the human erythrocyte membrane and molecular models.

While traces of manganese (Mn) take part in important and essential functions in biology, elevated exposures have been shown to cause significant toxicity. Chronic exposure to the metal leads to manganese neurotoxicity (or manganism), a brain disorder that resembles Parkinsonism. Toxic effect mechanisms of Mn is not understood, toxic concentrations of manganese are not well defined and blood manganese concentration at which neurotoxicity occurs has not been identified. There are reports indicating that the most abundant Mn-species in Mn carriers within blood is the Mn-citrate complex. Despite the well-documented information about the toxic effects of Mn, there are scarce reports concerning the effects of manganese compounds on both structure and functions of cell membranes, particularly those of human erythrocytes. With the aim to better understand the molecular mechanisms of the interaction of Mn with cell membranes, MnCl(2), and the Mn-citrate complex were incubated with intact erythrocytes, isolated unsealead human erythrocyte membranes (IUM), and molecular models of the erythrocyte membrane. These consisted in bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes present in the outer and inner monolayers of the erythrocyte membrane, respectively. The capacity of the Mn compounds to perturb the bilayer structures of DMPC and DMPE was evaluated by X-ray diffraction, IUM were studied by fluorescence spectroscopy, and intact human erythrocytes were observed by scanning electron microscopy (SEM). In all these systems it was found that Mn(2+) exerted considerable higher structural perturbations than the Mn-citrate complex.

Lipase of Candida albicans induces activation of NADPH oxidase and L-arginine pathways on resting and activated macrophages.

Candida albicans secretes various hydrolytic enzymes which are considered to be an integral part in the pathogenesis. However, the role of lipases is far from being completely understood and the direct effects of these fungal enzymes during the host-pathogen interaction remain to be established. We recently isolated and characterized an extracellular C. albicans lipase (CaLIP), and demonstrated the ability of this fungal enzyme to interact directly with macrophages (Mvarphi) and hepatocytes and to operate as a virulence factor. Herein, we explored the effects of CaLIP on Mvarphi functions such as oxidative burst and l-arginine metabolism. The study was performed in cells with different activation status: normal-resting Mvarphis and Mvarphis primed in vivo or in vitro with C. albicans. The ability of this fungal factor to modulate the above-mentioned parameters was dependent on cells status, dose, and microenvironment, where the interaction took place. These results constitute a new finding in the biology of candidiasis and could illustrate an additional evolutive advantage for the fungus in the framework of the bidirectional host-pathogen interaction.

Structural effects of Zn(2+) on cell membranes and molecular models.

Zinc is an essential element for nutrition as well as for the proper development and function of brain cells, and its traces are present in a wide range of foods. It is a constituent of many enzyme systems and is an integral part of insulin and of the active site of intracellular enzymes. However, excessive accumulation of zinc or its release from the binding sites may become detrimental for neurons. With the aim to better understand the molecular mechanisms of the interaction of zinc ions with cell membranes, it was incubated with intact human erythrocytes, isolated unsealed human erythrocyte membranes (IUM), cholinergic murine neuroblastoma cells, and molecular models of cell membranes. These consisted in bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes present in the outer and inner monolayers of most plasmatic cell membranes, particularly that of human erythrocytes, respectively. The capacity of zinc ions to perturb the bilayer structures of DMPC and DMPE was assessed by X-ray diffraction, DMPC large unilamellar vesicles (LUV) and IUM were studied by fluorescence spectroscopy, intact human erythrocytes were observed with scanning electron microscopy (SEM), and neuroblastoma cell morphology was observed under inverted microscope. This study presents evidence that 0.1mM Zn and higher concentrations affect cell membrane and molecular models.

Interpretación de los conocimientos que influyen en la adherencia a la dietoterapia en adultos mayores con diabetes tipo 2 de una comuna rural / Interpretation of the knowledge about type 2 diabetes and compliance to dietotherapy among elderly living in rural areas suffering from this disease

Type 2 diabetes is one of the most prevalent chronic diseases in the country. Among the strategies for its treatment is education, a tool presented by the health team to modify risky behavior on these people, providing users information and some strategies for their self care. The objective of this study was to analyze the different factors associated to the knowledge of the pathology that influences the compliance to diet therapy treatment among elderly suffering from type 2 diabetes, who are regularly checked by a nutritionist in Yumbel’s Health Public System. Through a qualitative phenomenological-type study, a semi-structured interview was carried out to 14 people in standard conditions assessing the knowledge about the pathology in terms of the consequences and the treatment to follow. However, the knowledge does not determine whether people will choose to follow diet therapy, with the exception of people with knowledge of the consequences of the disease. In the final analysis, the knowledge of the pathology does not induce the majority of the elderly from rural areas to follow diet therapy.

La Diabetes tipo 2 es una de las enfermedades crónicas de gran prevalencia en el país. Entre las estrategias para su tratamiento se encuentra la educación, como herramienta que presenta el equipo de salud para modificar conductas de riesgo en estas personas, entregando a los usuarios conocimientos y otras estrategias para su autocuidado. El objetivo del estudio fue interpretar los factores asociados a los conocimientos que influyen en la adherencia al tratamiento dietoterapéutico en adultos mayores con Diabetes tipo 2 controlados por nutricionista en la Atención Primaria de Salud de la comuna de Yumbel. A través de un estudio cualitativo de tipo fenomenológico, se realizó una entrevista semiestructurada a 14 usuarios en condiciones estándar, obteniendo como resultado la presencia de conocimientos de su patología, referido a las consecuencias y los tratamientos a realizar. Sin embargo, estos conocimientos no determinan un alto nivel de adherencia a la dietoterapia, excepto en el caso de presentar algún tipo de secuela. Por lo tanto, se concluye que los conocimientos de la patología no favorecen una mayor adherencia a la dietoterapia por parte de adultos mayores de una zona rural del país.

Relationship between lipid peroxidation and rigidity in L-alpha-phosphatidylcholine-DPPC vesicles.

DPPC incorporation into egg-PC unilamellar vesicles reduces their oxidation rate beyond that expected from the unsaturated lipid dilution. Addition of the unsaturated lipids produces changes in the physical properties of the inner parts of the lipid bilayer, as sensed by fluorescence anisotropy of DPH, and in the hydrophilic/hydrophobic region, as sensed by the generalized polarization of laurdan. DPPC (30 mol%) incorporation into egg-PC vesicles produces a decrease in alkyl chain mobility in the inner part of the bilayer, evaluated by the increase of DPH fluorescence anisotropy, and a rise of the generalized polarization value of laurdan in the bilayer interface. It also leads to a decrease in the rate of water efflux promoted by a hypertonic shock. Oxidation of PC LUVs, promoted by AAPH, as sensed by oxygen uptake and MDA formation, leads to qualitatively similar results than DPPC addition: rigidification at the inner part and the surface of the liposomes, and a lower rate of water permeation. It is suggested that these changes could contribute to the observed decrease in oxidation rate with conversion.

Cr(III) exerts stronger structural effects than Cr(VI) on the human erythrocyte membrane and molecular models.

Chromium exists in many oxidation states, of which only the hexavalent Cr(VI) and the trivalent Cr(III) ions are stable under environmental conditions. It is generally reported that Cr(VI) is highly toxic while Cr(III) is relatively innocuous, although others have reported just the opposite. On the other hand, despite the many studies on chromium toxicity, and particularly after the knowledge that Cr(VI) anions readily enter the erythrocytes where they are reduced to Cr(III), there are practically no reports on the structural effects induced by chromium compounds on the erythrocyte membrane. With the aim to better understand the molecular mechanisms of the interaction of Cr(III) and Cr(VI) with cell membranes, CrCl(3), and K(2)CrO(4) were incubated with intact erythrocytes, isolated unsealed human erythrocyte membranes (IUM), and molecular models of the erythrocyte membrane. These consisted in bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylcholine (DMPE), phospholipid classes present in the outer and inner monolayers of the erythrocyte membrane, respectively. The capacity of Cr(III) and Cr(VI) to perturb the bilayer structures of DMPC and DMPE was evaluated by X-ray diffraction, DMPC large unilamellar vesicles (LUV) and IUM were studied by fluorescence spectroscopy, and intact human erythrocytes were observed with scanning electron microscopy (SEM). In all these systems, it was found that Cr(III) induced considerably higher structural perturbations than Cr(VI).

Human erythrocytes are affected in vitro by extracts of Ugni molinae leaves.

Ugni molinae Turcz, also known as "Murtilla", is a plant that grows in the south of Chile. Infusions of their leaves have long been used in traditional native herbal medicine. The chemical composition of the leaves indicates the presence of polyphenols, which have antioxidant properties. In order to evaluate the mechanisms of their antioxidant properties and the toxicity of the aqueous extracts of leaves, the extracts were induced to interact with human red cells, their isolated unsealed membranes (IUM) and large unilamellar vesicles (LUV) of dimyristoylphosphatidyltidylcholine (DMPC), representative of phospholipid classes located in the outer monolayer of the erythrocyte membrane. Scanning electron microscopy (SEM) observations indicated that the extracts achieved a significant alteration in the shape of the erythrocytes as they changed their discoid shape to echinocytes. According to the bilayer couple hypothesis, the shape change indicates that the polyphenols were located in the outer moiety of the red cell membrane. This conclusion was confirmed by the fluorescence experiments performed in IUM and DMPC LUV. In fact, the extracts produced slight initial increases followed by sharp decreases at higher concentrations in the anisotropy and general polarization parameters. These results imply that the extracts induced structural perturbations in the acyl chain and polar group packing arrangements of the erythrocyte IUM and DMPC LUV lipid bilayers: first ordering and afterwards disordering them as the extract concentration increased.

Human erythrocytes are affected by the organochloride insecticide chlordane.

Chlordane is a widely used organochlorine insecticide. In order to evaluate its perturbing effect upon the morphology of human erythrocytes it was caused to interact with human red cells and molecular models of cell membranes. These consisted in bilayers of dimyristoylphosphatidylethanolamine (DMPE) and of dimyristoylphosphatidylcholine (DMPC), representative of phospholipid classes located in the inner and outer monolayers of the erythrocyte membrane, respectively. Scanning electron microscopy (SEM) observations indicated that this pesticide induced a significant alteration in the shape of the erythrocytes as they changed their discoid shape to spherocytes. According to the bilayer couple hypothesis, the shape changes induced in erythrocytes by foreign molecules are due to differential expansion of their two monolayers. The fact that chlordane produced spherocytes would indicate that the pesticide was equally located in the outer and the inner moieties of the red cell membrane. This conclusion was supported by the results obtained from X-ray diffraction studies. These showed that the hydrophobic and polar head regions of DMPC bilayers were perturbed when the insecticide was in a 1:10 molar ratio with respect to the lipid. These results were confirmed by the fluorescence experiments performed in DMPC large unilamellar vesicles (LUV). Chlordane produced a sharp decrease in the anisotropy and general polarization parameters in the 0-0.1 mM range, implying an increase in the fluidity at the acyl chain and polar region of DMPC. On the other hand, the bilayer structure of DMPE was perturbed in a fashion similar to that observed by X-ray diffraction in DMPC, a fact that explains the morphological change induced by chlordane to the human erythrocytes.

Structural effects of titanium citrate on the human erythrocyte membrane.

The structural effects of titanium citrate on the human erythrocyte membrane were studied through its interaction with intact erythrocytes and isolated unsealed human erythrocyte membranes (IUM). The studies were carried out by scanning electron microscopy and fluorescence spectroscopy, respectively. Titanium citrate induced shape changes in erythrocytes, which were damaged and ruptured leaving empty and retracted membranes. Fluorescence spectroscopy measurements in IUM indicated a disordering effect at both the polar head group and the acyl chain packing arrangements of the membrane phospholipid bilayer. Titanium citrate also interacted with molecular models of the erythrocyte membrane consisting in bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representing classes of phospholipids located in the outer and inner monolayers of the erythrocyte membrane, respectively. X-ray diffraction indicated that titanium citrate induced structural perturbation of the polar head group and of the hydrophobic acyl regions of DMPC, while the effects on DMPE bilayers were negligible. This conclusion is supported by fluorescence spectroscopy measurements on DMPC large unilamellar vesicles. All these findings indicate that the structural perturbations induced by titanium to human erythrocytes can be extended to other cells, thereby affecting their functions.