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Resumen: Introducción: diseñar preguntas de opción múltiple (POM) con Microsoft Bing (Copilot) para evaluar su calidad e índices psicométricos en educación médica. Material y métodos: se diseñó un examen de 180 preguntas con Microsoft Bing. Este fue evaluado por educadores médicos en términos de relevancia y calidad de distractores. Luego, tras administrarse a estudiantes, se calcularon los índices de dificultad y discriminación. Resultados: la mayoría de preguntas fueron de alta relevancia y los distractores de alta calidad. Los índices de discriminación y dificultad de las preguntas fueron aceptables en la mayoría de preguntas. Conclusión: Microsoft Bing (Copilot) podría usarse como sustituto de ChatGPT para el diseño de POM dadas las evidencias de validez recolectadas en el estudio. Abstract: Introduction: To design multiple-choice questions (MCQs) using Microsoft Bing (Copilot) and evaluate their quality and psychometric indices in medical education. Materials and methods: A 180-question exam was designed using Microsoft Bing. It was evaluated by medical educators in terms of relevance and distractor quality. After administering the exam to students, difficulty and discrimination indices were calculated. Results: Most questions were highly relevant, and the distractors were of high quality. The discrimination and difficulty indices were acceptable for the majority of the questions. Conclusion: Microsoft Bing (Copilot) could be used as a substitute for ChatGPT in designing MCQs, given the evidence of validity collected in the study.

This paper presents the performance evaluation of an amplify-and-forward (AF) relay-assisted multiuser multiple input-multiple output (MU-MIMO) downlink transmission system for correlated fading channels. The overall system performance was improved by incorporating a double-quadrature spatial modulation (DQSM) scheme. The bit error rate (BER) performance and detection complexity of the AF-MU-MIMO-DQSM system were analyzed and com-pared with those of a conventional AF-MU-MIMO system under the same conditions and parameters. The results showed that the correlated fading channel severely affected the performance of systems with higher spectral efficiency (SE). Considering an SE of 12 bpcu/user, the AF-MU-MIMO-DQSM system yielded a gain of up to 3 dB in BER performance compared with that of its conventional counterpart for the analyzed cases. In terms of detection com-plexity, the AF-MU-MIMO-DQSM system showed a reduction of up to 56 % compared with that of the conventional system for the optimal maximum likelihood detection criterion.

Abstract Effective treatment of breast cancer relies heavily on early detection. Routine annual mammography is a widely accepted screening technique that has resulted in significantly improving the survival rate. However, it suffers from low sensitivity resulting in high false positives from screening. To overcome this problem, adjunctive technologies such as ultrasound are employed on about 10% of women recalled for additional screening following mammography. These adjunctive techniques still result in a significant number of women, about 1.6%, who undergo biopsy while only 0.4% of women screened have cancers. The main reason for missing cancers during mammography screening arises from the masking effect of dense breast tissue. The presence of a tumor results in the alteration of temperature field in the breast, which is not influenced by the tissue density. In the present paper, the IRI-Numerical Engine is presented as an adjunct for detecting cancer from the surface temperature data. It uses a computerized inverse heat transfer approach based on Pennes’s bioheat transfer equations. Validation of this enhanced algorithm is conducted on twenty-three biopsy-proven breast cancer patients after obtaining informed consent under IRB protocol. The algorithm correctly predicted the size and location of cancerous tumors in twenty-four breasts, while twenty-two contralateral breasts were also correctly predicted to have no cancer (one woman had bilateral breast cancer). The tumors are seen as highly perfused and metabolically active heat sources that alter the surface temperatures that are used in heat transfer modeling. Furthermore, the results from this study with twenty-four biopsy-proven cancer cases indicate that the detection of breast cancer is not affected by breast density. This study indicates the potential of the IRI-Numerical Engine as an effective adjunct to mammography. A large scale clinical study in a statistically significant sample size is needed before integrating this approach in the current protocol.

Kaempferol, a flavonoid present in many food products, has chemical and cellular antioxidant properties that are beneficial for protection against the oxidative stress caused by reactive oxygen and nitrogen species. Kaempferol administration to model experimental animals can provide extensive protection against brain damage of the striatum and proximal cortical areas induced by transient brain cerebral ischemic stroke and by 3-nitropropionic acid. This article is an updated review of the molecular and cellular mechanisms of protection by kaempferol administration against brain damage induced by these insults, integrated with an overview of the contributions of the work performed in our laboratories during the past years. Kaempferol administration at doses that prevent neurological dysfunctions inhibit the critical molecular events that underlie the initial and delayed brain damage induced by ischemic stroke and by 3-nitropropionic acid. It is highlighted that the protection afforded by kaempferol against the initial mitochondrial dysfunction can largely account for its protection against the reported delayed spreading of brain damage, which can develop from many hours to several days. This allows us to conclude that kaempferol administration can be beneficial not only in preventive treatments, but also in post-insult therapeutic treatments.

Lipid membrane nanodomains or lipid rafts are 10–200 nm diameter size cholesterol- and sphingolipid-enriched domains of the plasma membrane, gathering many proteins with different roles. Isolation and characterization of plasma membrane proteins by differential centrifugation and proteomic studies have revealed a remarkable diversity of proteins in these domains. The limited size of the lipid membrane nanodomain challenges the simple possibility that all of them can coexist within the same lipid membrane domain. As caveolin-1, flotillin isoforms and gangliosides are currently used as neuronal lipid membrane nanodomain markers, we first analyzed the structural features of these components forming nanodomains at the plasma membrane since they are relevant for building supramolecular complexes constituted by these molecular signatures. Among the proteins associated with neuronal lipid membrane nanodomains, there are a large number of proteins that play major roles in calcium signaling, such as ionotropic and metabotropic receptors for neurotransmitters, calcium channels, and calcium pumps. This review highlights a large variation between the calcium signaling proteins that have been reported to be associated with isolated caveolin-1 and flotillin-lipid membrane nanodomains. Since these calcium signaling proteins are scattered in different locations of the neuronal plasma membrane, i.e., in presynapses, postsynapses, axonal or dendritic trees, or in the neuronal soma, our analysis suggests that different lipid membrane-domain subtypes should exist in neurons. Furthermore, we conclude that classification of lipid membrane domains by their content in calcium signaling proteins sheds light on the roles of these domains for neuronal activities that are dependent upon the intracellular calcium concentration. Some examples described in this review include the synaptic and metabolic activity, secretion of neurotransmitters and neuromodulators, neuronal excitability (long-term potentiation and long-term depression), axonal and dendritic growth but also neuronal cell survival and death.

Amyloid β (Aβ) oligomers are the most neurotoxic forms of Aβ, and Aβ(1–42) is the prevalent Aβ peptide found in the amyloid plaques of Alzheimer’s disease patients. Aβ(25–35) is the shortest peptide that retains the toxicity of Aβ(1–42). Aβ oligomers bind to calmodulin (CaM) and calbindin-D28k with dissociation constants in the nanomolar Aβ(1–42) concentration range. Aβ and histidine-rich proteins have a high affinity for transition metal ions Cu2+, Fe3+ and Zn2+. In this work, we show that the fluorescence of Aβ(1–42) HiLyteTM-Fluor555 can be used to monitor hexa-histidine peptide (His6) interaction with Aβ(1–42). The formation of His6/Aβ(1–42) complexes is also supported by docking results yielded by the MDockPeP Server. Also, we found that micromolar concentrations of His6 block the increase in the fluorescence of Aβ(1–42) HiLyteTM-Fluor555 produced by its interaction with the proteins CaM and calbindin-D28k. In addition, we found that the His6-tag provides a high-affinity site for the binding of Aβ(1–42) and Aβ(25–35) peptides to the human recombinant cytochrome b5 reductase, and sensitizes this enzyme to inhibition by these peptides. In conclusion, our results suggest that a His6-tag could provide a valuable new tool to experimentally direct the action of neurotoxic Aβ peptides toward selected cellular targets.

Highly neurotoxic A1-reactive astrocytes have been associated with several human neurodegenerative diseases. Complement protein C3 expression is strongly upregulated in A1 astrocytes, and this protein has been shown to be a specific biomarker of these astrocytes. Several cytokines released in neurodegenerative diseases have been shown to upregulate the production of amyloid β protein precursor (APP) and neurotoxic amyloid β (Aβ) peptides in reactive astrocytes. Also, aberrant Ca2+ signals have been proposed as a hallmark of astrocyte functional remodeling in Alzheimer’s disease mouse models. In this work, we induced the generation of A1-like reactive astrocytes after the co-treatment of U251 human astroglioma cells with a cocktail of the cytokines TNF-α, IL1-α and C1q. These A1-like astrocytes show increased production of APP and Aβ peptides compared to untreated U251 cells. Additionally, A1-like astrocytes show a (75 ± 10)% decrease in the Ca2+ stored in the endoplasmic reticulum (ER), (85 ± 10)% attenuation of Ca2+ entry after complete Ca2+ depletion of the ER, and three-fold upregulation of plasma membrane calcium pump expression, with respect to non-treated Control astrocytes. These altered intracellular Ca2+ dynamics allow A1-like astrocytes to efficiently counterbalance the enhanced release of Ca2+ from the ER, preventing a rise in the resting cytosolic Ca2+ concentration.

Abstract The purpose of this article is to evaluate the shear strength parameters of mixtures of sandy soil with high asphalt emulsion contents for their use in geotechnical structures, such as zoned earth dams, embankments, etc. The methodology adopted consisted of: collecting and characterizing samples of sandy soil to be laboratory tested; compacting the mixtures between soils and asphalt emulsion with contents varying between 13% and 28% in weight by using different compaction methodologies; and performing direct shear tests to evaluate the parameters governing the shear strength behavior of the manufactured mixtures. Results showed that the use of a high asphalt emulsion content contributed to greater homogeneity of the mixtures. It was also found that the presence of residual asphalt gave a bilinear behavior to the sandy soil for the failure envelopes obtained from direct shear tests. At normal stresses usually less than 100 kPa, the mixtures present a cohesive intercept due the existing residual binder, while for normal stresses higher than 200 kPa, the mixtures presented a friction angle equal to the matrix of sandy soil used.

Abstract Background The hemolysin (Hly) secretion system of E. coli allows the one-step translocation of hemolysin A (HlyA) from the bacterial cytoplasm to the extracellular medium, without a periplasmic intermediate. In this work, we investigate whether the Hly secretion system of E. coli is competent to secrete a repertoire of functional single-domain VHH antibodies (nanobodies, Nbs), facilitating direct screening of VHH libraries and the purification of selected Nb from the extracellular medium. Results We employed a phagemid library of VHHs obtained by immunization of a dromedary with three protein antigens from enterohemorrhagic E. coli (EHEC), namely, the extracellular secreted protein A (EspA), the extracellular C-terminal region of Intimin (Int280), and the translocated intimin receptor middle domain (TirM). VHH clones binding each antigen were enriched and amplified by biopanning, and subsequently fused to the C-terminal secretion signal of HlyA to be expressed and secreted in a E. coli strain carrying the Hly export machinery (HlyB, HlyD and TolC). Individual E. coli clones were grown and induced in 96-well microtiter plates, and the supernatants of the producing cultures directly used in ELISA for detection of Nbs binding EspA, Int280 and TirM. A set of Nb sequences specifically binding each of these antigens were identified, indicating that the Hly system is able to secrete a diversity of functional Nbs. We performed thiol alkylation assays demonstrating that Nbs are correctly oxidized upon secretion, forming disulphide bonds between cysteine pairs despite the absence of a periplasmic intermediate. In addition, we show that the secreted Nb-HlyA fusions can be directly purified from the supernatant of E. coli cultures, avoiding cell lysis and in a single affinity chromatography step. Conclusions Our data demonstrate the Hly secretion system of E. coli can be used as an expression platform for screening and purification of Nb binders from VHH repertories.

Las cardiopatías congénitas (CC) se definen como una anomalía estructural del corazón o de los grandes vasos intratorácicos. Constituyen la malformación congénita más frecuente al nacimiento. Al menos un tercio de los pacientes requieren algún tipo de intervención antes del año de edad. Las manifestaciones clínicas de las cardiopatías en la etapa neonatal se presentan con un amplio contexto clínico y se pueden confundir con problemas a nivel pulmonar o infeccioso, lo que dificulta su diagnóstico y con ello contribuyendo de forma importante a la mortalidad y morbilidad de estos pacientes, ya que se retrasa el diagnóstico y manejo oportuno. El monitoreo por oximetría de pulso en el periodo neonatal se utiliza actualmente como método diagnóstico para la detección de cardiopatías congénitas críticas; a pesar de que las detecta en forma temprana, en muchos países aún no se lleva a cabo. El objetivo de este artículo es ofrecer un panorama general de la presentación clínica, aspectos diagnósticos y manejo inicial de las CC en el primer año de edad que pueda ser de utilidad a los médicos de primer contacto para mejorar la atención en este grupo de pacientes.

In this work, we measured the effect of cytochrome c on the NADH-dependent superoxide anion production by synaptic plasma membrane vesicles from rat brain. In these membranes, the cytochrome c stimulated NADH-dependent superoxide anion production was inhibited by antibodies against cytochrome b5 reductase linking the production to this enzyme. Measurement of the superoxide anion radical generated by purified recombinant soluble and membrane cytochrome b5 reductase corroborates the production of the radical by different enzyme isoforms. In the presence of cytochrome c, a burst of superoxide anion as well as the reduction of cytochrome c by cytochrome b5 reductase was measured. Complex formation between both proteins suggests that cytochrome b5 reductase is one of the major partners of cytochrome c upon its release from mitochondria to the cytosol during apoptosis. Superoxide anion production and cytochrome c reduction are the consequences of the stimulated NADH consumption by cytochrome b5 reductase upon complex formation with cytochrome c and suggest a major role of this enzyme as an anti-apoptotic protein during cell death.

Plasma membrane calcium ATPases (PMCA) are key proteins in the maintenance of calcium (Ca2+) homeostasis. Dysregulation of PMCA function is associated with several human pathologies, including neurodegenerative diseases, and, therefore, these proteins are potential drug targets to counteract those diseases. Gold compounds, namely of Au(I), are well-known for their therapeutic use in rheumatoid arthritis and other diseases for centuries. Herein, we report the ability of dichloro(2-pyridinecarboxylate)gold(III) (1), chlorotrimethylphosphinegold(I) (2), 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidenegold(I) chloride (3), and chlorotriphenylphosphinegold(I) (4) compounds to interfere with the Ca2+-ATPase activity of pig brain purified PMCA and with membranes from SH-SY5Y neuroblastoma cell cultures. The Au(III) compound (1) inhibits PMCA activity with the IC50 value of 4.9 µM, while Au(I) compounds (2, 3, and 4) inhibit the protein activity with IC50 values of 2.8, 21, and 0.9 µM, respectively. Regarding the native substrate MgATP, gold compounds 1 and 4 showed a non-competitive type of inhibition, whereas compounds 2 and 3 showed a mixed type of inhibition. All gold complexes showed cytotoxic effects on human neuroblastoma SH-SY5Y cells, although compounds 1 and 3 were more cytotoxic than compounds 2 and 4. In summary, this work shows that both Au (I and III) compounds are high-affinity inhibitors of the Ca2+-ATPase activity in purified PMCA fractions and in membranes from SH-SY5Y human neuroblastoma cells. Additionally, they exert strong cytotoxic effects.

Los ensayos «Charlot o el histrionismo» y «Charlie Chaplin: el sospechoso», de María Zambrano y Hannah Arendt, respectivamente, dan origen a una reflexión sobre la condición del exiliado en el siglo XX, a partir del arte de Charles Chaplin. En él, las autoras hacen un análisis de la propuesta artística del actor, basada en el hombre marginado por la sociedad, pero reflejada en la suya propia. Charlot se convierte en objeto de la mirada para discutir sobre exilio, las razones del arte y el valor de la palabra frente al silencioPalabras clave: Exilio, clown, payaso, arte, Chaplin, silencio, palabra. AbstractIn the essays «Charlot or the histrionics» and «Charlie Chaplin: the suspect», Maria Zambrano and Hanna Arendt –respectively– reflect about exiled people condition in the 20th century, from the artistic poetics of Charles Chaplin. Both philosophers use art and clowning, to analyze outsider and marginalized social condition in their time, lived personally in their own experience as exiled people. Thus, Charlot becomes for them a privileged witness to discuss about exile, art and the value of the word and silence.Key words: Exile, outsider, clown, art, Chaplin, word, silence.

This paper presents a technique, based on the matrix pencil method (MPM), for the compression of underwater acoustic signals produced by boat engines. The compressed signal, represented by its complex resonance expansion, is intended to be sent over a low-bit-rate wireless communication channel. We demonstrate that the method can provide data compression greater than 60%, ensuring a correlation greater than 93% between the reconstructed and the original signal, at a sampling frequency of 2.2 kHz. Once the signal was reconstituted, a localization process was carried out with the time reversal method (TR) using information from four different sensors in a simulation environment. This process sought to achieve the identification of the position of the ship using only passive sensors, considering two different sensor arrangements.

Este artículo presenta los resultados del proceso de reconocimiento de huellas digitales acústicas utilizando características espectrales de la señal. El Análisis de Componentes Principales (PCA, por sus siglas en inglés) se aplica para reducir la dimensión de las características extraídas y luego se implementa un clasificador basado en el método de los k-vecinos más cercanos (KNN) para identificar el patrón de la señal de audio. Este clasificador se compara con una Red Neuronal Artificial (ANN, por sus siglas en inglés). Es necesario implementar un sistema de filtrado para las señales adquiridas para reducir el ruido de 60 Hz generadas por las imperfecciones en el sistema de adquisición. Los métodos descritos en este trabajo se utilizaron para el reconocimiento de embarcaciones marinas

The apoptosis of cerebellar granule neurons (CGN) induced by low-potassium in serum free medium in vitro has become a widely used model for neuronal apoptosis during in vivo brain development. In this review we shall summarize first the basic features of this model for neuronal apoptosis. Next, we shall focus on the L-type calcium channels (LTCC) inactivation as the primary pro-apoptotic signal in low K+-induced CGN death. This apoptotic process can be split into two major and sequential cellular signaling phases: one reversible phase that offers a temporal window for therapeutic interventions to prevent neuronal death, and an irreversible later phase. Therefore, we shall comment next the critical role of reactive oxygen species (ROS) production and major ROS sources triggering the entry of CGN in the irreversible stages of low K+-induced apoptosis. Then, we shall present the experimental evidences showing clustering of LTCC and ROS producing enzymes in plasma membrane lipid rafts of CGN matured in vitro, which have opened new perspectives for cell signaling in the early and reversible phase of this apoptosis. The role of lipid rafts nanodomains as fast response calcium/nitric oxide transducers of the switch of CGN to low K+ medium will be discussed next. The two major conclusions drawn from this review are: (1) deregulation of the pool of cytochrome b5 reductase associated to plasma membrane-lipid rafts, at least in part due to overexpression of cytochrome b5, can account for the critical superoxide anion overshot which triggers the entry in the irreversible phase of low K+ apoptosis of CGN, and (2) LTCC inactivation is rapidly transduced by lipid rafts nanodomains into a large drop of cytosolic calcium, a switch-off of nitric oxide production and subsequent inactivation of survival signaling pathways dependent on the activity of CaMKII, PKA and Akt/PKB kinases.

Objective. Characterize the follicular dynamics and luteal growth and regression pattern of multiparous (MB) and heifer (BH) Murrah buffaloes in Colombian tropical conditions. Material and methods. Ten MB and ten BH were synchronized with a progesterone-releasing intravaginal device. No artificial insemination was performed during the estrous and daily ultrasound examinations were performed 15 days later to determine the number and diameter of the structures present in both ovaries in the subsequent natural estrous cycle. The Student’s T test was used to evaluate differences between MB and BH. All data are presented as mean ± standard deviation. Results. The length of the estrous cycle was 22.00±4.50 days for MB and 22.00±2.70 days for BH. Follicular growth occurs in one (n=1; 5.89%), two (n=14; 82.35%) or three waves (n=2; 11.76%). The first wave initiated the day after ovulation with the recruitment of 8.33±2.06 and 10.00±2.72 follicles in MB and BH, while the second wave started on day 11.00±2.00 and 10.50±2.82, presenting 8.37±2.26 and 8.00±1.51 follicles. The third wave began on day 16.21±3.10 showing 6.50±1.70 follicles, only BM had three waves. The maximum luteal diameter was 19.58±4.16 mm and 17.74±3.32 mm respectively. There were no significant differences between the groups for these variables. Conclusions. These results show that the follicular development in buffaloes occurs in waves, where two waves is the most common pattern, as previously reported by other authors.

ABSTRACT The Gram-positive bacterium Lactococcus lactis, used for the production of cheeses and other fermented dairy products, falls victim frequently to fortuitous infection by tailed phages. The accompanying risk of dairy fermentation failures in industrial facilities has prompted in-depth investigations of these phages. Lactococcal phage Tuc2009 possesses extensive genomic homology to phage TP901-1. However, striking differences in the baseplate-encoding genes stimulated our interest in solving the structure of this host’s adhesion device. We report here the X-ray structures of phage Tuc2009 receptor binding protein (RBP) and of a “tripod” assembly of three baseplate components, BppU, BppA, and BppL (the RBP). These structures made it possible to generate a realistic atomic model of the complete Tuc2009 baseplate that consists of an 84-protein complex: 18 BppU, 12 BppA, and 54 BppL proteins. The RBP head domain possesses a different fold than those of phages p2, TP901-1, and 1358, while the so-called “stem” and “neck” domains share structural features with their equivalents in phage TP901-1. The BppA module interacts strongly with the BppU N-terminal domain. Unlike other characterized lactococcal phages, Tuc2009 baseplate harbors two different carbohydrate recognition sites: one in the bona fide RBP head domain and the other in BppA. These findings represent a major step forward in deciphering the molecular mechanism by which Tuc2009 recognizes its saccharidic receptor(s) on its host. IMPORTANCE Understanding how siphophages infect Lactococcus lactis is of commercial importance as they cause milk fermentation failures in the dairy industry. In addition, such knowledge is crucial in a general sense in order to understand how viruses recognize their host through protein-glycan interactions. We report here the lactococcal phage Tuc2009 receptor binding protein (RBP) structure as well as that of its baseplate. The RBP head domain has a different fold than those of phages p2, TP901-1, and 1358, while the so-called “stem” and “neck” share the fold characteristics also found in the equivalent baseplate proteins of phage TP901-1. The baseplate structure contains, in contrast to other characterized lactococcal phages, two different carbohydrate binding modules that may bind different motifs of the host’s surface polysaccharide.

Introduction Trypanosoma evansi was first identified in the Canary Islands in 1997, and is still present in a small area of the Archipelago. To date, the disease has exclusively affected camel herds, and has not been detected in any other animal hosts. However potential vectors of Trypanosoma evansi must be identified. Methods One Nzi trap was placed on a camel farm located in the infected area for a period of one year. Results Two thousand five hundred and five insects were trapped, of which Stomoxys calcitrans was the sole hematophagous vector captured. Conclusions Stomoxys calcitrans could be exclusively responsible for the transmission of Trypanosoma evansi among camels in the surveyed area, as other species do not seem to be infected by S. calcitrans in the presence of camels.

A multicentre, cross-sectional study was carried out in six centres across Canada to establish a national standard for pulmonary function tests using healthy, lifetime nonsmokers, with each centre aiming to test 10 men and 10 women from each decade from 20 to 80 years of age. Data from each centre were used to derive prediction equations for each centre, and pooled data from all centres (total: 327 women and 300 men) were used to derive Canadian predicted equations. The predictive models were compared with three widely used published models for selected tests. It was found that, in general, the equations modelled for each centre could be replaced by the models obtained when pooling all data (Canadian model). Comparisons with the published references showed good agreement and similar slopes for most tests. The results suggest that pulmonary function test results obtained from different centres in Canada were comparable and that standards currently used remain valid for Canadian Caucasians.

Screening of antibody (Ab) libraries by direct display on the surface of E. coli cells is hampered by the presence of the outer membrane (OM). In this work we demonstrate that the native β-domains of EhaA autotransporter and intimin, two proteins from enterohemorrhagic E. coli O157:H7 (EHEC) with opposite topologies in the OM, are effective systems for the display of immune libraries of single domain Abs (sdAbs) from camelids (nanobodies or VHH) on the surface of E. coli K-12 cells and for the selection of high affinity sdAbs using magnetic cell sorting (MACS). We analyzed the capacity of EhaA and intimin β-domains to display individual sdAbs and sdAb libraries obtained after immunization with the extracellular domain of the translocated intimin receptor from EHEC (TirM(EHEC)). We demonstrated that both systems displayed functional sdAbs on the surface of E. coli cells with little proteolysis and cellular toxicity, although E. coli cells displaying sdAbs with the β-domain of intimin showed higher antigen-binding capacity. Both E. coli display libraries were screened for TirM(EHEC) binding clones by MACS. High affinity binders were selected by both display systems, although more efficiently with the intimin β-domain. The specificity of the selected clones against TirM(EHEC) was demonstrated by flow cytometry of E. coli cells, along with ELISA and surface plasmon resonance with purified sdAbs. Finally, we employed the E. coli cell display systems to provide an estimation of the affinity of the selected sdAb by flow cytometry analysis under equilibrium conditions.

Three diamidines (DB 75, DB 867 and DB 1192) were selected and their ability to cure T. evansi experimentally infected goats was investigated. A toxicity assessment and pharmacokinetic analysis of these compounds were additionally carried out. Goats demonstrated no signs of acute toxicity, when treated with four doses of 1 mg/kg/day (total dose 4 mg/kg). Complete curative efficacy of experimentally infected goats was seen in the positive control group treated with diminazene at 5 mg/kg and in the DB 75 and DB 867 groups treated at 2.5 mg/kg. Drug treatment was administered once every second day for a total of seven days. Complete cure was also seen in the group of goats treated with DB 75 at 1.25 mg/kg. DB 1192 was incapable of curing goats at either four-times 2.5 mg/kg or 1.25 mg/kg. Pharmacokinetic analysis clearly demonstrated that the treatment failures of DB 1192 were due to sub-therapeutic compound levels in goat plasma, whilst compound levels for DB 75 and DB 867 remained well within the therapeutic window. In conclusion, two diamidine compounds (DB 75 and DB 867) presented comparable efficacy at lower doses than the standard drug diminazene and could be considered as potential clinical candidates against T. evansi infection.

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(parágrafo do texto) Este projeto toma como preocupação básica as tarefas de preservação e valorização do patrimônio cultural do país: a "memória nacional", isto é, o conhecimento de nossa identidade, de nossa vida social. E isto diz respeito diretamente, portanto, ao homem brasi-leiro na sua integralidade.

A palimpsest is a writing erased and replaced by another. Sometimes, perhaps all too often, our lives become incarnated palimpsests thanks to the prevailing biopolitics, which refers not only to the government of the living, but also to the multiple practices of dying and disappearing. Can art teach us to create new spaces of co-habitation with our essential ghosts, with those who refuse to abandon us despite everything? In this article we address the work entitled Palimpsesto, in which the Colombian artist Doris Salcedo (Bogotá, 1958), makes visible one of the most ignominious events in our recent history: the deaths of thousands of people in the Mediterranean due to indifference and, on occasions, the complicity—conscious or unconscious—of a desensitized European society, closed in on itself. In Palimpsesto, the artist creates a space where those absences are permanently present in absentia. However, Salcedo’s art goes beyond testimony and representation: the tears that flow from the earth itself, outlining on the ground the names of women and men who drowned while fleeing war, reveal not only the need to name those who are no longer with us, but could lay the foundations to erect a kind of divinology (Meillassoux, “Deuil à venir” 105) through which new ties and forms of dwelling would be built, beyond interested political use, between human beings and those harassing absences.