1,721,068 research outputs found
Low level laser therapy as an antimicrobial and anti-biofilm technology and its relevance to wound healing
No full textThe biostimulative effect of low-level laser therapy (LLLT) in tissues has been noted in reference to the treatment of various diseases but little information exists on its effectiveness on chronic wounds and biofilm. The scope of this review was to identify literature reporting on LLLT alone, without photodynamic agents, as an antimicrobial/antibiofilm technology and determine its effects on wound healing. Overall the beneficial effects of LLLT in promoting wound healing in animal and human studies has been demonstrated. However, the lack of credible studies using reproducible models and light dosimetry restricts the analysis of current data. Efforts must be addressed to standardize phototherapy procedures as well as to develop suitable in vitro and in vivo biofilm models to test LLLT efficacy in promoting biofilm eradication and wound healing
Morphological changes in HAV-infected Frp/3 cells and immunolocalization of HAAg
No full textElectron and immunoelectron microscopic studies were carried out on HAV-infected Frp/3 cells. The infection led to a distinctive cytopathic effect (CPE) arising on day 3 up to the complete detachment of monolayers on day 7. Infected cells exhibited progressive modifications, beginning from the formation of long helical polyribosomes. Subsequently, hypertrophy, cisternal dilatation and degranulation of the RER could be observed. Furthermore, the formation of concentric membranous bodies (CMB), large myelin-like structures and annulate lamellae could be revealed at later times of infection. 24-27 nm virus-like particles were observed within cytoplasmic vesicles or outside extensively degenerated cells. Indirect immunoperoxidase staining were used to localize HAV antigen (HAAg) in thin sectioned infected Frp/3 cells. Vesicular inclusion bodies, often seen to contain electron-lucent particles, resulted darkly stained as well as tracts of the RER and myelin-like structures. Negatively stained preparations from cell lysates revealed small clusters of HAV particles which sometimes appeared to be still associated with residual membrane fragments. Our findings seem to suggest that HAV replication occurs in close association with cytoplasmic membranes and a direct involvement of the RER seems to be demonstrated
Assessing the Integration of Electrified On-Board Systems in an MDAO framework for a small transport aircraft
Full text linkThe integration of on-board systems design within the aircraft design process is often
considered only in the late part of the initial design. This is acceptable for civil aircraft using
standard technology systems. However, facing with MEA and AEA concepts and different
possible architectures, the systems design and the assessment of their effects on the overall
aircraft should be moved up in the usual design process. This paper deals with evaluation of
the effect of different on-board systems architecture, with a different electrification level, on
the overall aircraft design. These effects have been evaluated using three different MDA
workflows developed within the AGILE4.0 European research project. The workflows are
defined with an increasing number of disciplines to show how the effect of a proper selection
of a systems architecture is differently caught by each one. In this way it is possible to define
which disciplines should be included for the systems architecture assessment. The results show
a save of 1% of MTOM for the AEA applied to a small turboprop aircraft when only the OBS
mass is assessed. Increasing workflow complexity, adding performance and engine design the
save increase to 1.2%. Finally, the save increases to 1.3% when the effect on engine SFC is
also considered
The effectiveness of photodynamic therapy on planktonic cells and biofilms and its role in wound healing
No full textPhotodynamic therapy (PDT) is the application of a photoactive dye followed
by irradiation that leads to the death of microbial cells in the presence of oxygen. Its use for
controlling biofilms has been documented in many areas, particularly oral care. However,
the potential use of PDT in the treatment of chronic wound-associated microbial biofilms
has sparked much interest in the field of wound care. The aim of this article is to provide
an overview on the effectiveness of PDT on in vitro and in vivo biofilms, their potential
application in both the prevention and management of wound biofilm infections and their
prospective role in the enhancement of wound healing.Photodynamic therapy (PDT) is the application of a photoactive dye followed by irradiation that leads to the death of microbial cells in the presence of oxygen. Its use for controlling biofilms has been documented in many areas, particularly oral care. However, the potential use of PDT in the treatment of chronic wound-associated microbial biofilms has sparked much interest in the field of wound care. The aim of this article is to provide an overview on the effectiveness of PDT on in vitro and in vivo biofilms, their potential application in both the prevention and management of wound biofilm infections and their prospective role in the enhancement of wound healing
Poloxamer 338 affects cell adhesion and biofilm formation in escherichia coli: Potential applications in the management of catheter-associated urinary tract infections
Full text linkPoloxamers are nontoxic, amphiphilic copolymers used in different formulations. Due to its surfactant properties, Poloxamer 338 (P388) is herein proposed as a strategy to avoid biofilm formation often causing recalcitrant catheter-associated urinary tract infections (CAUTI). The aim is to evaluate the ability of P388 coatings to affect the adhesion of Ec5FSL and Ec9FSL Escherichia coli strains on silicone urinary catheters. Attenuated total reflection infrared spectroscopy, atomic force microscopy, and static water contact angle measurement were employed to characterize the P388-coated silicone catheter in terms of amount of P388 layered, coating thickness, homogeneity, and hydrophilicity. In static conditions, the antifouling power of P388 was defined by comparing the E. coli cells adherent on a hydrophilic P388-adsorbed catheter segment with those on an uncoated one. A P388-coated catheter, having a homogeneous coverage of 35 nm in thickness, reduced of 0.83 log10 and 0.51 log10 the biofilm of Ec5FSL and Ec9FSL, respectively. In dynamic conditions, the percentage of cell adhesion on P388-adsorbed silicone channels was investigated by a microfluidic system, simulating the in vivo conditions of catheterized patients. As a result, both E. coli isolates were undetected. The strong and stable antifouling property against E. coli biofilm lead us to consider P388 as a promising anti-biofilm agent for CAUTIs control
Searching the point of no return in Helicobacter pylori life: necrosis and/or programmed death.
No full textAims: Ultrastructural and molecular studies to support the hypothesis of programmed cell
death in Helicobacter pylori were conducted.
Methods and Results: Evidence of programmed death in H. pylori is provided through
electron microscopic detection and cytochemical labelling of electrondense bodies (EDB),
1 containing packaged DNA in coccoid cells, resembling micronuclei of apoptotic eukaryotic
cells. This morphological evidence is also supported by DNA cleavage in homogeneous
fragments of about 100 base pairs. Programmed cell death was observed in H. pylori cultures at
37 °C, with a maximum of 37á5% of EDB coccoid cells after 7 days. The non-permissive
temperature of 4 °C anticipated this process, with 40% of EDB coccoid forms within 3 days,
and it remained substantially unaffected during the observation time of 14 days.
Conclusion: In these experiments, deprivation of nutrients and a non-permissive temperature
acted as a powerful trigger for programmed cell death.
Significance and Impact of the Study: Helicobacter pylori bacterial populations, under
2 stressing stimuli, can respond with programmed cell suicide as a means of species preservation
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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