Dose and volume de-escalation of radiotherapy in head and neck cancer.

Radiotherapy plays a key role in the treatment of head and neck cancer. However, irradiation of the head and neck region is associated with high rates of acute and chronic toxicity. Technological advances have led to better visualisation of target volumes and critical structures and improved dose conformality in the treatment volume. Despite this, acute toxicity has not been substantially reduced and late toxicity has a significant impact on patients' quality of life. The greater radiosensitivity of tumours associated with the HPV and the development of new imaging techniques have encouraged research into new deintensified strategies to reduce the side effects of radiotherapy. The aim of this paper is to review the literature on the strategies of de-escalated treatment in dose and/or volume in head and neck cancer.

Clinical guide to perioperative management for videothoracoscopy lung resection (Section of Cardiac, Vascular and Thoracic Anesthesia, SEDAR; Spanish Society of Thoracic Surgery, SECT; Spanish Society of Physiotherapy).

The introduction of video-assisted thoracoscopic (VATS) techniques has led to a new approach in thoracic surgery. VATS is performed by inserting a thoracoscope through a small incisions in the chest wall, thus maximizing the preservation of muscle and tissue. Because of its low rate of morbidity and mortality, VATS is currently the technique of choice in most thoracic procedures. Lung resection by VATS reduces prolonged air leaks, arrhythmia, pneumonia, postoperative pain and inflammatory markers. This reduction in postoperative complications shortens hospital length of stay, and is particularly beneficial in high-risk patients with low tolerance to thoracotomy. Compared with conventional thoracotomy, the oncological results of VATS surgery are similar or even superior to those of open surgery. This aim of this multidisciplinary position statement produced by the thoracic surgery working group of the Spanish Society of Anesthesiology and Reanimation (SEDAR), the Spanish Society of Thoracic Surgery (SECT), and the Spanish Association of Physiotherapy (AEF) is to standardize and disseminate a series of perioperative anaesthesia management guidelines for patients undergoing VATS lung resection surgery. Each recommendation is based on an in-depth review of the available literature by the authors. In this document, the care of patients undergoing VATS surgery is organized in sections, starting with the surgical approach, and followed by the three pillars of anaesthesia management: preoperative, intraoperative, and postoperative anaesthesia.

Guía clínica en el manejo perioperatorio para la cirugía de resección pulmonar por videotoracoscopia (Sección de Anestesia Cardiaca, Vascular y Torácica, SEDAR; Sociedad Española de Cirugía Torácica, SECT; Asociación Española de Fisioterapia, AEF) / Clinical guide to perioperative management for videothoracoscopy lung resection (Section of Cardiac, Vascular and Thoracic Anesthesia, SEDAR; Spanish Society of Thoracic Surgery, SECT; Spanish Society of Physiotherapy)

La introducción de técnicas toracoscópicas asistidas por video en cirugía torácica (VATS) ha permitido realizar un nuevo enfoque en la cirugía torácica. El acceso videotoracoscópico se realiza con pequeñas incisiones, preservando al máximo los músculos y los tejidos. En la actualidad, la VATS se considera de elección en la mayoría de los procedimientos torácicos, principalmente debido a la menor morbimortalidad asociada. La resección pulmonar por VATS presenta reducción de las fugas de aire prolongadas, arritmias, neumonía, dolor postoperatorio y una disminución de los marcadores inflamatorios. Esta reducción de las complicaciones postoperatorias está vinculada a una reducción de la estancia hospitalaria, siendo los pacientes de alto riesgo y con poca tolerancia a la toracotomía los principales beneficiarios de esta técnica.En comparación con la toracotomía convencional, los?resultados?oncológicos de la cirugía VATS son similares o incluso superiores a los de la cirugía abierta.Este documento, de redacción multidisciplinar, consensuado por el grupo de trabajo de cirugía torácica de la Sociedad Española de Anestesiología y Reanimación (SEDAR), de la Sociedad Española de Cirugía Torácica (SECT) y la Asociación Española de Fisioterapia (AEF), pretende estandarizar y difundir, con base en la bibliografía más actual, las mejores pautas de manejo clínico perioperatorio de los pacientes que se someten a una cirugía de resección pulmonar por VATS. Cada recomendación parte de una revisión de la literatura disponible y analizada en profundidad por los autores.Con el objetivo de dirigir el curso asistencial que seguirá el paciente que se somete a una cirugía pulmonar por VATS, esta guía se organiza inicialmente en el enfoque quirúrgico, seguido de los tres puntos clásicos del proceso anestésico. Estos puntos son preoperatorio, intraoperatorio y postoperatorio.(AU)

The introduction of video-assisted thoracoscopic (VATS) techniques has led to a new approach in thoracic surgery. VATS is performed by inserting a thoracoscope through a small incisions in the chest wall, thus maximizing the preservation of muscle and tissue. Because of its low rate of morbidity and mortality, VATS is currently the technique of choice in most thoracic procedures. Lung resection by VATS reduces prolonged air leaks, arrhythmia, pneumonia, postoperative pain and inflammatory markers. This reduction in postoperative complications shortens hospital length of stay, and is particularly beneficial in high-risk patients with low tolerance to thoracotomy.Compared with conventional thoracotomy, the oncological results of VATS surgery are similar or even superior to those of open surgery.This aim of this multidisciplinary position statement produced by the thoracic surgery working group of the Spanish Society of Anesthesiology and Reanimation (SEDAR), the Spanish Society of Thoracic Surgery (SECT), and the Spanish Association of Physiotherapy (AEF) is to standardize and disseminate a series of perioperative anaesthesia management guidelines for patients undergoing VATS lung resection surgery. Each recommendation is based on an in-depth review of the available literature by the authors.In this document, the care of patients undergoing VATS surgery is organized in sections, starting with the surgical approach, and followed by the three pillars of anaesthesia management: preoperative, intraoperative, and postoperative anaesthesia.(AU)

Absceso tubo-ovárico por granulicatella adiacens. Descripción de un caso / Tubo-ovarian abscess due to granulicatella adiacens. A review of a case

La mayoría de los abscesos tubo-ováricos son debidos a complicaciones asociadas a la enfermedad inflamatoria pélvica. Sin embargo, una minoría son secundarios a otros procesos como neoplasias o patologías intrabdominales. Se presenta el caso de un absceso tubo-ovárico, en una mujer de 36 años, intervenida previamente de apendicectomía. En el cultivo del material de drenaje del absceso creció Granulicatella adiacens, un microrganismo no involucrado habitualmente en este tipo de infecciones. Tras la descripción del caso, se discute la etiología de los abscesos tubo-ováricos y las peculiaridades del microorganismo implicado. (AU)

Most tubo-ovarian abscesses are due to complications associated with pelvic inflammatory disease. However, a minority are second-ary to other processes such as neoplasms or intraabdominal pathologies. A case of tubo-ovarian abscess is presented, in a 36-year-old woman, previously operated on for appendectomy. Granulicatella adiacens, a microorganism not usually involved in this type of infection, grew in the culture of the drainage material of the abscess. After the description of the case, the etiology of the tubo-ovarian abscesses and the peculiarities of the microorganism involved are discussed. (AU)

Clinical guide to perioperative management for videothoracoscopy lung resection (Section of Cardiac, Vascular and Thoracic Anesthesia, SEDAR; Spanish Society of Thoracic Surgery, SECT; Spanish Society of Physiotherapy). / Guía clínica en el manejo perioperatorio para la cirugía de resección pulmonar por videotoracoscopia (Sección de Anestesia Cardiaca, Vascular y Torácica, SEDAR; Sociedad Española de Cirugía Torácica, SECT; Asociación Española de Fisioterapia, AEF).

The introduction of video-assisted thoracoscopic (VATS) techniques has led to a new approach in thoracic surgery. VATS is performed by inserting a thoracoscope through a small incisions in the chest wall, thus maximizing the preservation of muscle and tissue. Because of its low rate of morbidity and mortality, VATS is currently the technique of choice in most thoracic procedures. Lung resection by VATS reduces prolonged air leaks, arrhythmia, pneumonia, postoperative pain and inflammatory markers. This reduction in postoperative complications shortens hospital length of stay, and is particularly beneficial in high-risk patients with low tolerance to thoracotomy. Compared with conventional thoracotomy, the oncological results of VATS surgery are similar or even superior to those of open surgery. This aim of this multidisciplinary position statement produced by the thoracic surgery working group of the Spanish Society of Anesthesiology and Reanimation (SEDAR), the Spanish Society of Thoracic Surgery (SECT), and the Spanish Association of Physiotherapy (AEF) is to standardize and disseminate a series of perioperative anaesthesia management guidelines for patients undergoing VATS lung resection surgery. Each recommendation is based on an in-depth review of the available literature by the authors. In this document, the care of patients undergoing VATS surgery is organized in sections, starting with the surgical approach, and followed by the three pillars of anaesthesia management: preoperative, intraoperative, and postoperative anaesthesia.

Causes of death in patients with locally advanced head and neck cancer treated with radiotherapy and systemic therapy.

BACKGROUND: To investigate the incidence of non-cancer mortalities and prognostic factors associated with competitive causes of death in a homogeneous cohort of patients with locally advanced head and neck cancer treated with radiotherapy and systemic treatment. METHODS: This study included 284 patients with locally advanced head and neck cancer treated with radiotherapy and systemic treatment between 2005 and 2017. The cumulative incidence of death associated with tumour, second tumours, treatment, side effects and comorbidity was calculated. A Fine and Gray regression model was used to investigate factors associated with cancer and competitive mortality. RESULTS: The cumulative incidence of tumoral death at 5 and 10 years were 35 and 47% respectively, whereas the cumulative incidence of competitive mortality were 10 and 12% respectively. In the multivariate analysis, age and comorbidity were independent factors for non-cancer mortality. Patients with a high risk of non-cancer mortality presented a cumulative incidence of 17.3% at 5 years and 18.4% at 10 years. CONCLUSIONS: This study demonstrated a high incidence of competing mortality in older patients with comorbidities. Non-cancer deaths should be considered when selecting patients for combination therapies and in the study design ofclinical trials.

Comparison of higher order aberrations in amblyopic and non-amblyopic eyes in pediatric patients with anisometropic amblyopia.

Purpose: To compare the ocular higher order aberrations (HOAs) for the physiologic pupil size in amblyopic and non-amblyopic eyes of patients with anisometropic amblyopia in pediatric age group. Methods: Children between 5 and 15 years age having treatment naïve anisometropic amblyopia; after a detailed examination by a pediatric ophthalmologist; underwent assessment of wavefront aberrations for both amblyopic and non-amblyopic eyes at their physiologic pupil sizes using i-Trace ray tracing wavefront aberrometer. The axial lengths were also measured using IOL Master 500. The RMS values of the total ocular higher order aberrations (HOAs) and those arising from internal and corneal components of the two eyes were tabulated and compared to look for differences. Comparison of total ocular aberrations for pre-determined refractive error groups was also done for amblyopic and non-amblyopic eyes separately. Results: Eighty-eight eyes of 44 subjects were included for analysis. Mean pupil size was comparable in between amblyopic and non-amblyopic eyes (3.98 mm vs. 4.07 mm, P = 0.346). The mean axial lengths of the two eyes were comparable (amblyopic eyes 23.13 mm vs. non-amblyopic eyes 22.88 mm, P = 0.419). Significant differences in total HOAs and those arising from the internal optics (except spherical aberrations) of the eye were noted between the two eyes. There were no differences in the corneal HOAs. The total HOAs were comparable amongst the various refractive error groups for amblyopic and non-amblyopic eyes individually. Conclusion: There are significant differences in ocular HOAs between amblyopic and non-amblyopic eyes in children with anisometropic amblyopia.

The volcano mouse Neotomodon alstoni of central Mexico, a biological model in the study of breeding, obesity and circadian rhythms.

The "Mexican volcano mouse" Neotomodon alstoni, is endemic of the Transverse Neovolcanic Ridge in central Mexico. It is considered as least concern species and has been studied as a potential laboratory model from different perspectives. Two lines of research in neuroendocrinology have been addressed: reproduction and parental care, particularly focused on paternal attention and the influence of testosterone, and studies on physiology and behavior of circadian rhythms, focused on the circadian biology of the species, its circadian locomotor activity and daily neuroendocrine regulation of metabolic parameters related to energy balance. Some mice, when captive, spontaneously develop obesity, which allows for comparisons between lean and obese mice of daily changes in neuronal and metabolic parameters associated with changes in food intake and locomotor activity. This review includes studies that consider this species an attractive animal model where the alteration of circadian rhythms influences the pathogenesis of obesity, specifically with the basic regulation of food intake and metabolism and differences related to sex. This study can be considered as a reference to the comparative animal physiology among rodents.

Zika virus epidemiology: from Uganda to world pandemic, an update.

Zika virus (ZIKV) infection is an emergent worldwide public health problem. Historically, 84 countries have reported vector-borne ZIKV transmission, 61 of which report on-going transmission. It is a Flavivirus transmitted through arthropods belonging to the Aedes genus. Since 2015, ZIKV infections have increased dramatically; with 1.3 million people infected during 2015 in Brazil alone. This paper's objective is to highlight the conjectural epidemiological points of the virus' dissemination. The digital archives Pubmed, MEDLINE, EMBASE and Cochrane were searched for papers that assessed aspects of ZIKV transmission and epidemiology. The first isolation occurred in Uganda in 1947. Since then, important outbreaks were documented globally. Consequently, an emergent public health problem arose from a rapidly increasing incidence and its association with the development of neurological diseases such as microcephaly and Guillain-Barré syndrome. Key factors in the successful containment of outbreaks include surveillance of mosquitos in the neighbourhood, an early mosquito control treatment, an assertive information campaign, and the involvement of the local population and healthcare workers. As such, while ZIKV seems to be spreading globally in a similar manner to other arboviruses, such as Dengue and Chikungunya viruses, it can also be rapidly contained due to the pre-existing availability of necessary resources and regulatory tools as control measures. This review aims to provide a description of those characteristics of ZIKV infection that may be useful in the construction of effective outbreak control strategies.

Decreased food anticipatory activity of obese mice relates to hypothalamic c-Fos expression.

During daily Food Restriction (FR), obese Neotomodon alstoni mice present decreased Food Anticipatory Activity (FAA) compared to lean mice. Here, we investigated whether FOS expression in hypothalamic nuclei involved in food synchronization and anticipation parallels decreased FAA during daily FR of obese N. alstoni. Locomotor activity of lean and obese mice in ad libitum feeding conditions was monitored for at least two weeks. Then, a gradual restriction of food access was followed to establish a 5h period of daily food access. FR was maintained during at least two weeks before sacrifice of mice at the starting point of the feeding period. Obese mice subjected to FR displayed an overall reduction of FOS-positive (FOS+) hypothalamic neurons, while lean mice in a similar protocol exhibited an increase in FOS+ neurons within the arcuate and dorsomedial hypothalamic nuclei. These results are consistent with decreased FAA displayed by obese mice in comparison to lean mice. Furthermore, limbic system areas of lean mice, such as the cingulate cortex and the hippocampus, showed an increase in FOS during FR, while no responses were observed in obese mice. The daily food intake of obese mice was severely reduced during FR, compared to the ad libitum condition, whereas food intake in lean mice was not affected by FR. Current data suggests that decreased hypothalamic and limbic neuronal activation may contribute to the reduction of FAA in obese N. alstoni mice.

Impact of damming on the Chironomidae of the upper zone of a tropical run-of-the-river reservoir / Impacto de um represamento sobre Chironomidae do remanso de um reservatório fio água tropical

Abstract We examined the effects of the Mogi-Guaçu river damming (São Paulo State, Brazil) on the Chironomidae fauna. Pre, during, and post-filling sampling was carried out in the main channel and margins of one site in the upper zone of the reservoir, using a modified Petersen grab (325 cm2). We evaluated the total, subfamily, and tribe densities and also their relative abundance. Analysis of genera included densities, relative abundance, richness, and dominance. The Rosso’s ecological value index (EVI) determined the ecological importance of each genus. There was a tendency of decrease of the total Chironomidae density, increase in the percentage of Chironomini, and decrease in densities and percentages of Orthocladiinae and Tanytarsini. These changes in percentage were respectively related to Polypedilum, Lopescladius, and Rheotanytarsus, the genera with the highest EVI values. After-filling richness was lower in the margins and dominance of genera did not change significantly. Chironomidae in the margins was more sensitive to damming than in the main channel. This difference in sensibility sustains the use of Chironomidae as bioindicators. Damming impact was indicated by the reduction of both genera richness in the margins and relative abundance of groups typical of faster waters. The results have highlighted the need for multi-habitat analysis combined with a before-after sampling approach in the environmental impact studies concerning the damming impact on the benthic fauna.

Resumo Este trabalho teve como objetivo avaliar o impacto do represamento do Rio Mogi-Guaçu, em um ponto situado na zona de remanso do reservatório, através da utilização da taxocenose Chironomidae. A amostragem foi realizada antes, durante e após o represamento, no canal e nas margens, com o auxílio de um pegador Petersen modificado (área de 325 cm2). Calculou-se a densidade total, de subfamílias, tribos e gêneros de Chironomidae, bem como sua abundância relativa. Estimou-se a riqueza e a dominância de gêneros. O índice de valor ecológico de Rosso (IVE) foi utilizado para avaliar a importância ecológica dos diferentes gêneros. Houve tendência de redução da densidade total de Chironomidae, aumento da abundância relativa de Chironomini e diminuição das abundâncias relativas de Orthocladiinae e Tanytarsini. Estas alterações de abundância relativa foram relacionadas respectivamente a Polypedilum, Lopescladius e Rheotanytarsus, gêneros que apresentaram os maiores valores de IVE. Após o represamento, houve decréscimo da riqueza de gêneros na margem, enquanto a dominância não apresentou alteração significativa. A taxocenose de Chironomidae das margens mostrou-se mais sensível ao represamento que a do canal. Esta diferença de sensibilidade confirma o potencial dos Chironomidae como bioindicadores. A ocorrência de impacto foi observada através da diminuição da riqueza de gêneros nas margens e da abundância relativa de táxons característicos de águas mais rápidas. Os resultados chamam atenção para a necessidade de utilizar a abordagem de múltiplos habitats combinada com a amostragem antes e depois do evento na avaliação dos impactos causados por represamento sobre a fauna bentônica.

Artificial reproduction of magnetic fields produced by a natural geomagnetic storm increases systolic blood pressure in rats.

The incidence of geomagnetic storms may be associated with changes in circulatory physiology. The way in which the natural variations of the geomagnetic field due to solar activity affects the blood pressure are poorly understood and require further study in controlled experimental designs in animal models. In the present study, we tested whether the systolic arterial pressure (AP) in adult rats is affected by simulated magnetic fields resembling the natural changes of a geomagnetic storm. We exposed adult rats to a linear magnetic profile that simulates the average changes associated to some well-known geomagnetic storm phases: the sudden commencement and principal phase. Magnetic stimulus was provided by a coil inductor and regulated by a microcontroller. The experiments were conducted in the electromagnetically isolated environment of a semi-anechoic chamber. After exposure, AP was determined with a non-invasive method through the pulse on the rat's tail. Animals were used as their own control. Our results indicate that there was no statistically significant effect in AP when the artificial profile was applied, neither in the sudden commencement nor in the principal phases. However, during the experimental period, a natural geomagnetic storm occurred, and we did observe statistically significant AP increase during the sudden commencement phase. Furthermore, when this storm phase was artificially replicated with a non-linear profile, we noticed a 7 to 9 % increase of the rats' AP in relation to a reference value. We suggested that the changes in the geomagnetic field associated with a geomagnetic storm in its first day could produce a measurable and reproducible physiological response in AP.

Impact of damming on the Chironomidae of the upper zone of a tropical run-of-the-river reservoir.

We examined the effects of the Mogi-Guaçu river damming (São Paulo State, Brazil) on the Chironomidae fauna. Pre, during, and post-filling sampling was carried out in the main channel and margins of one site in the upper zone of the reservoir, using a modified Petersen grab (325 cm2). We evaluated the total, subfamily, and tribe densities and also their relative abundance. Analysis of genera included densities, relative abundance, richness, and dominance. The Rosso's ecological value index (EVI) determined the ecological importance of each genus. There was a tendency of decrease of the total Chironomidae density, increase in the percentage of Chironomini, and decrease in densities and percentages of Orthocladiinae and Tanytarsini. These changes in percentage were respectively related to Polypedilum, Lopescladius, and Rheotanytarsus, the genera with the highest EVI values. After-filling richness was lower in the margins and dominance of genera did not change significantly. Chironomidae in the margins was more sensitive to damming than in the main channel. This difference in sensibility sustains the use of Chironomidae as bioindicators. Damming impact was indicated by the reduction of both genera richness in the margins and relative abundance of groups typical of faster waters. The results have highlighted the need for multi-habitat analysis combined with a before-after sampling approach in the environmental impact studies concerning the damming impact on the benthic fauna.

Environmental Effects on the Photophysics of Organic-Inorganic Halide Perovskites.

The photophysical properties of films of organic-inorganic lead halide perovskites under different ambient conditions are herein reported. We demonstrate that their luminescent properties are determined by the interplay between photoinduced activation and darkening processes, which strongly depend on the atmosphere surrounding the samples. We have isolated oxygen and moisture as the key elements in each process, activation and darkening, both of which involve the interaction with photogenerated carriers. These findings show that environmental factors play a key role in the performance of lead halide perovskites as efficient luminescent materials.

A new Bayesian network-based approach to the analysis of sperm motility: application in the study of tench (Tinca tinca) semen.

In this study a Bayesian network (BN) has been built for the study of the objective motility of Tinca tinca spermatozoa (spz). Semen from eight 2-year-old sexually mature male tenchs was obtained and motility analyses were performed at 6-17, 23-34 and 40-51 s after activation, using computer-assisted sperm analysis (CASA) software. Motility parameters rendered by CASA were treated with a two-step cluster analysis. Three well-defined sperm subpopulations were identified, varying the proportion of spermatozoa contained in each cluster with time and male. Cluster, cinematic and time variables were used to build the BN to study the probabilistic relationships among variables and how each variable influenced the final sperm classification into one of three predefined clusters. Both network structure and conditional probabilities were calculated based on the collected data set. Results shown that almost all the variables were directly or indirectly related to each other. By doing probabilistic inference we observed that the cluster distribution corresponded to the definition provided by the cluster analysis. Also, velocity and time variables determined the cluster to which each spermatozoon belonged with a high degree of accuracy. Thus, BNs can be applied in the study of sperm motility. The construction of a BN that include fertility data opens a new way to try to clarify the roles of motility and other sperm quality indicators in fertilization.

Assessment of microsatellites in estimating inter- and intraspecific variation among Neotropical Crocodylus species.

We tested microsatellites that were developed for the saltwater crocodile (Crocodylus porosus) for cross-species amplification and to provide an estimate of inter- and intraspecific variation among four species of Neotropical crocodiles (C. rhombifer, C. intermedius, C. acutus, and C. moreletii). Our results indicated that with the exception of 2 loci in C. intermedius, all 10 microsatellite loci were successfully amplified in the 4 species, producing a set of variably sized alleles that ranged in number between 2 and 14 alleles per locus. Similarly, private alleles (i.e., unique alleles) also were reported in all 4 species for at least 3 loci. The mean observed and expected heterozygosities (averaged across species for all 10 loci combined) ranged from 0.39 to 0.77 and from 0.44 to 0.78, respectively. In addition to this, we evaluated these microsatellites in 2 populations of C. acutus and C. moreletii to assess their utility in estimating intraspecific levels of polymorphisms. These microsatellites also showed considerable allelic variation in population level analysis. The set of 10 microsatellite loci in our study had the potential to be used as a tool in population and conservation genetic studies of Neotropical crocodiles.

D-lactic acidosis: an unusual cause of encephalopathy in a patient with short bowel syndrome.

A 24-year-old woman with a short bowel syndrome following post-ischemic small bowel resection, developed several episodes of lethargy, echolalia and ataxia. D-lactic acidosis was identified as the cause of neurological disturbances. This infrequent disorder can be precipitated by intake of a large amount of sugars, in patients with short bowel syndrome. It should be suspected in the presence of metabolic acidosis with increased anion gap and a normal level of L-lactic acid. The diagnosis relies on the specific dosage of D-lactic stereoisomer. Proper management involves rehydration, diet adaptation and oral administration of poorly absorbed antibiotics in order to modify the colonic flora responsible for D-lactic production.

Properties of amphiphilic oligonucleotide films at the air/water interface and after film transfer.

The self-assembly of amphiphilic hybrid materials containing an oligonucleotide sequence at the air/water interface was investigated by means of pressure-molecular area (Π-A) isotherms. In addition, films were transferred onto solid substrates and imaged using scanning force microscopy. We used oligonucleotide molecules with lipid tails, which consisted of a single stranded oligonucleotide 11 mer containing two hydrophobically modified 5-(dodec-1-ynyl)uracil nucleobases (dU11) at the 5'-end of the oligonucleotide sequence. The air/water interface was used as confinement for the self-assembling process of dU11. Scanning force microscopy of films transferred via Langmuir-Blodgett technique revealed mono-, bi- (Π ≥ 2 mN/m) and multilayer formation (Π ≥ 30 mN/m). The first layer was 1.6 ± 0.1 nm thick. It was oriented with the hydrophilic oligonucleotide moiety facing the hydrophilic substrate while the hydrophobic alkyl chains faced air. In the second layer the oligonucleotide moiety was found to face the air. The second layer was found to cover up to 95% of the sample area. Our measurements indicated that the rearrangement of the molecules into bi- and multiple bilayers happened already at the air/water interface. Similar results were obtained with a second type of oligonucleotide amphiphile, an oligonucleotide block copolymer, which was composed of an oligonucleotide 11 mer covalently attached at the terminus to polypropyleneoxide (PPO).