1,710 research outputs found
Nanocarriers based on interpolyelectrolyte complexation of Sulphated polysaccharide-b- PEG diblock copolymers and PLL
Publicado em "Journal of Tissue Engeneering and Regenerative Medicine", vol. 7, supp. 1 (2013)Glycosaminoglycans (GAGs) are integral part of the closest cellular
environment: they can be found on the cells surface and in the extracellular
matrix, where they interact with different proteins acting as local
regulator of their activity. The use of GAGs in the preparation of protein
delivery nanosystems is, therefore, prominent but so far, underexploited
mainly because of the heterogeneity (composition and molecular
weights) of natural glycans and the multistep procedures needed to
obtain GAGs’ synthetic analogues and diblock copolymers.1 Recently,
we have shown that oxime click reaction can be applied as a straightforward
methodology for the synthesis of poly(ethylene glycol) (PEG)-
hyaluronic acid (HA) diblock copolymers.2 These copolymers formed
nanosized interpolyelectrolyte complexes (45 to 150 nm) by interaction
with poly- L -lysine (PLL).3 Unfortunately, these complexes are not stable
at physiological ionic strength. Herein, we describe a strategy to
overcome this drawback; chondroitin sulphate-b-PEG diblock copolymers
(CS-b-PEG) were obtained using the same oxime click reaction.
The stronger negative charge of sulphate groups (versus the carboxilic
groups present in HA) resulted in the complexes with higher stability:
interpolyelectrolyte complexes between PLL and (CS-b-PEG) are stable
up to 260 mM ionic strenght. Because carbohydrates do not activate Tcells,
we believe that the reported herein complexes have an enormous
potential in both drug delivery and vaccination fields
Evaluation of immunomodulatory effects of lactic acid bacteria in turbot (Scophthalmus maximus)
7 pages, 4 figures.In the present work, the effects of several lactic acid bacteria on the immune response of turbot (Scophthalmus
maximus) macrophages have been studied both in vitro and in vivo. Out of six lactic acid bacterial strains
tested, only heat-killed Lactococcus lactis significantly increased the turbot head kidney macrophage chemiluminescent
(CL) response after 24 h of incubation. Nitric oxide (NO) was also significantly enhanced by this
bacterium after 72 h of incubation with either viable (103 and 106 cells/ml) or heat-killed (106 cells/ml) bacteria.
Viable Leuconostoc mesenteroides (106 cells/ml) was also capable of significantly increasing NO production.
Since L. lactis proved to be the strain with more effects on the host immune function, further in vivo and in vitro
experiments were conducted with this bacterium. The in vitro capacity of L. lactis to adhere to turbot intestinal
mucus was positively confirmed. When orally administered, L. lactis significantly increased the macrophage CL
response and the serum NO concentration after 7 days of daily administration. The antibacterial effect of the
extracellular products from the six LAB strains against the fish-pathogenic bacterium Vibrio anguillarum was
also demonstrated in vitro.This work was partially supported by the project 1FD97-0044-C03-03 from FEDER funds and a grant from Caixa Galicia (Spain). L. Villamil acknowledges the University of Vigo for a research fellowship. C. Tafalla acknowledges the Consejo Superior de Investigaciones
CientĂficas (CSIC) for a research fellowship.Peer reviewe
Continuous atom laser with Bose-Einstein condensates involving three-body interactions
We demonstrate, through numerical simulations, the emission of a coherent
continuous matter wave of constant amplitude from a Bose-Einstein Condensate in
a shallow optical dipole trap. The process is achieved by spatial control of
the variations of the scattering length along the trapping axis, including
elastic three body interactions due to dipole interactions. In our approach,
the outcoupling mechanism are atomic interactions and thus, the trap remains
unaltered. We calculate analytically the parameters for the experimental
implementation of this CW atom laser.Comment: 11 pages, 4 figure
Human Papillomavirus (HPV) Genotyping: Automation and Application in Routine Laboratory Testing
A large number of assays designed for genotyping human papillomaviruses (HPV) have been developed in the last years. They perform within a wide range of analytical sensitivity and specificity values for the different viral types, and are used either for diagnosis, epidemiological studies, evaluation of vaccines and implementing and monitoring of vaccination programs. Methods for specific genotyping of HPV-16 and HPV-18 are also useful for the prevention of cervical cancer in screening programs. Some commercial tests are, in addition, fully or partially automated. Automation of HPV genotyping presents advantages such as the simplicity of the testing procedure for the operator, the ability to process a large number of samples in a short time, and the reduction of human errors from manual operations, allowing a better quality assurance and a reduction of cost. The present review collects information about the current HPV genotyping tests, with special attention to practical aspects influencing their use in clinical laboratories
BN 52021 (a platelet activating factor-receptor antagonist) decreases alveolar macrophage-mediated lung injury in experimental extrinsic allergic alveolitis.
Several lines of research indirectly suggest that platelet activating factor (PAF) may intervene in the pathogenesis of extrinsic allergic alveolitis (EAA). The specific aim of our study was to evaluate the participation of PAF on macrophage activation during the acute phase of EAA in an experimental model of this disease developed in guinea pigs. Initially we measured the concentration of PAF in bronchoalvedar lavage fluid, blood and lung tissue. In a second phase we evaluate the participation of PAF on alveolar macrophage activation and parenchymal lung injury. The effect of PAF on parenchymal lung injury was evaluated by measuring several lung parenchymatous lesion indices (lung index, bronchoalvedar lavage fluid (BALF) lactic hydrogenase activity and BALF alkaline phosphatase activity) and parameters of systemic response to the challenge (acute phase reagents). We observed that induction of the experimental EAA gave rise to an increase in the concentration of PAF in blood and in lung tissue. The use of the PAF-receptor antagonist BN52021 decreases the release of lysosomal enzymes (beta-glucuronidase and tartrate-sensitive acid phosphatase) to the extracellular environment both in vivo and in vitro. Furthermore, antagonism of the PAF receptors notably decreases pulmonary parenchymatous lesion. These data suggest that lung lesions from acute EAA are partly mediated by local production of PAF
TACTICAL BLOCKCHAIN TO PROVIDE DATA PROVENANCE IN SUPPORT OF INTERNET OF BATTLEFIELD THINGS AND BIG DATA ANALYTICS
This capstone project evaluated the use of blockchain technology to address a number of challenges with increasing amounts of disparate sensor data and an information-rich landscape that can quickly overwhelm effective decision-making processes. The team explored how blockchain can be used in a variety of defense applications to verify users, validate sensor data fed into artificial intelligence models, limit access to data, and provide an audit trail across the data life cycle. The team developed a conceptual design for implementing blockchain for tactical data, artificial intelligence, and machine learning applications; identified challenges and limitations involved in implementing blockchain for the tactical domain; described the benefits of blockchain for these various applications; and evaluated this project’s findings to propose future research into a wider set of blockchain applications. The team did this through the development of three use cases. One use case demonstrated the use of blockchain at the tactical edge in a “data light” information environment. The second use case explored the use of blockchain in securing medical information in the electronic health record. The third use case studied blockchain’s application in the use of multiple sensors collecting data for chemical weapons defense to support measurement and signature intelligence analysis using artificial intelligence and machine learning.Civilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyApproved for public release. Distribution is unlimited
Influencia de las bacterias psicrĂłtrofas en la actividad proteolĂtica de la leche
La refrigeraciĂłn de la leche reduce el ritmo de multiplicaciĂłn y actividad de los microorganismos, pero ha generado nuevos problemas relacionados con el crecimiento y la actividad de los microorganismos psicrĂłtrofos, que son aquellos que crecen a temperaturas inferiores a 7 °C, independientemente de su temperatura Ăłptima. Estos microorganismos producen enzimas termoestables que degradan algunos componentes de la leche deteriorando su calidad y la de sus derivados, y disminuyendo los rendimientos queseros. Con el fin de evaluar la actividad proteolĂtica de las bacterias psicrĂłtrofas sobre las caseĂnas y su relaciĂłn con la temperatura y tiempo de almacenamiento de la leche, se inocularon diferentes lotes de leche con este tipo de bacterias, hasta obtener recuentos de 104 y 105 unidades formadoras de colonia por mililitro (ufc/ml); como control se utilizĂł leche que no recibiĂł inoculaciĂłn con recuento de psicrĂłtrofos de 103 ufc/ml. DespuĂ©s de almacenar la lechea4y7°Cdurante tres y seis dĂas, se evaluĂł la actividad proteolĂtica sobre las caseĂnas. Al almacenar leche durante tres dĂas a 4 y 7 °C, no se presentĂł actividad proteolĂtica cuando el recuento inicial de psicrĂłtrofos era del orden de 103 ufc/ml, mientras que cuando dicho recuento fue superior a 104 ufc/ml se observĂł actividad proteolĂtica, siendo más intensa a 7 °C que a 4 °C. Con almacenamiento de seis dĂas, solamente la leche conservada a 4 °C con recuento inicial de 103 ufc/ml no presentĂł actividad proteolĂtica, los demás tratamientos mostraron gran actividad proteolĂtica sobre la fracciĂłn de caseĂnas aumentando dicha actividad a medida que aumenta el grado de contaminaciĂłn
Tratamiento quirúrgico de las metástasis diafisarias de huesos largos en pacientes oncológicos estadio IV
La incidencia de enfermedad metastásica ósea se ha incrementado debido a la mayor supervivencia
de los pacientes con cáncer. El esqueleto es la tercera localización mas frecuente de metástasis procedentes de
tumores primarios. Se evalĂşan las indicaciones quirĂşrgicas para evitar la apariciĂłn de fracturas patolĂłgicas y
los resultados obtenidos en metástasis diafisarias de huesos largos. Cincuenta lesiones han sido tratadas en 48
pacientes. En todos los casos se estabilizĂł con un clavo intramedular. La supervivencia media fue de 11 meses (2
dĂas-48 meses). Al final del seguimiento la puntuaciĂłn media en la escala MSTS fue 25/30 y 27/30 para miembro
superior e inferior respectivamente. Debe considerarse la radioterapia postoperatoria para disminuir la progre
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sión de la enfermedad. Hay múltiples factores a tener en cuenta en el tratamiento de pacientes con metástasis
Ăłseas incluyendo comorbilidades, caracterĂsticas histolĂłgicas del tumor primario, la expectativa de vida y acti
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vidad del paciente y el dolor.The incidence of metastatic bone disease is increasing as patients with cancer living longer. The
skeleton is the third most common site for metastasis that originates from primary carcinomas. We evaluated the
indications for surgery to prevent pathological fractures and the results obtained in metastases of the diaphyseal
long bones. Fifty metastases bone lesion were treated in 48 patients. In all cases an intramedullary nail was in
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serted. The chance of surviving was 11 moths average (2 days-48 moths). At follow-up, the MSTS average was
25/30 and 27/30 for superior and inferior limb respectively. To minimize disease progression postoperative ex
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ternal-beam irradiation should be considered. There are multiples factors to consider in the treatment of patients
with bone metastasic, including comorbidities, the histological characteristics of the primary tumor, the expected
life span of the patient, the patient ?s activity level and pain
Soil biochemical alterations and microbial community responses under Acacia dealbata Link invasion.
A critical outcome of the invasive processes of exotic plants is the impact on soil microbial communities and chemical parameters. We studied the impact of Acacia dealbata on soils of mixed forests and
shrublands. We hypothesized that A. dealbata can alter soil microbial community function and soil chemical profile in invaded ecosystems. Two sampling dates were selected depending on the phonological stage of A. dealbata (vegetative vs. reproductive).
Soil chemical parameters were deeply modified in the invaded sites. Total C and N, P, K, Ca, Mg, NO3 and NH4Ăľ content and available P, were significantly higher in invaded soils of both mixed forests and
shrublands. Soil microbial community activities were affected by the sampling date, soil type and ecosystem. Enzymatic activities mainly varied in soils collected during the vegetative stage of A. dealbata
in mixed forests and during both vegetative and reproductive stages in shrublands. Soils invaded by A. dealbata showed increased acid phosphatase, b-glucosidase and N-acetyl glucosaminidase activities and the geometrical mean of these activities. Soil basal respiration was significantly reduced in invaded patches of mixed forests. Our results showed an alteration of soil chemistry and microbial community function related to A. dealbata presence, probably leading to acceleration in the decomposition and mineralization rates
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