296 research outputs found
Xanthan gum as an alternative to replace fat for coating and flavoring the extruded snacks
Food industries adapt their products and processes
to the needs and desires of consumers. Extruded
snacks include 10β20% fat sprinkled to fix flavors, seasonings,
and salt. Considering the need to flavor snacks and
simultaneously reduce the intake of calories, a polysaccharide
is proposed in this study as a fat replacer. Impact of
aqueous xanthan gum (Xg) solutions (0.25, 0.5, 1.0%)
under two pH conditions (3.5 and 7.0) on structural and
sensory characteristics of extruded snacks was analyzed.
Rheological features of the coating solutions, as flow
behaviour and viscoelastic profile (storage and loss moduli),
were assessed. Texture analysis, to evaluate the snacks
firmness and moisture content, water activity, retraction,
and agglomeration index of the coated snacks, were also
evaluated. Results for the aqueous Xg coatings were very
encouraging showing good coating properties, not damaging
the texture of the extrudates or causing agglomeration.
Sensory analysis reflected a good overall acceptability of
these snacks, as compared to oil-coated snacks. Therefore,
xanthan gum should be used by the industry, to replace fat,
on extruded snacks flavor coating solutionsinfo:eu-repo/semantics/publishedVersio
Theory of Multidimensional Solitons
We review a number of topics germane to higher-dimensional solitons in
Bose-Einstein condensates. For dark solitons, we discuss dark band and planar
solitons; ring dark solitons and spherical shell solitons; solitary waves in
restricted geometries; vortex rings and rarefaction pulses; and multi-component
Bose-Einstein condensates. For bright solitons, we discuss instability,
stability, and metastability; bright soliton engineering, including pulsed atom
lasers; solitons in a thermal bath; soliton-soliton interactions; and bright
ring solitons and quantum vortices. A thorough reference list is included.Comment: review paper, to appear as Chapter 5a in "Emergent Nonlinear
Phenomena in Bose-Einstein Condensates: Theory and Experiment," edited by P.
G. Kevrekidis, D. J. Frantzeskakis, and R. Carretero-Gonzalez
(Springer-Verlag
Pain control after total knee arthroplasty: a randomized trial comparing local infiltration anesthesia and continuous femoral block
Local infiltration analgesia (LIA) is a new multimodal wound infiltration method. It
has attracted growing interest in recent years and is widely used all over the world for
treating postoperative pain after knee and hip arthroplasty. This method is based on
systematic infiltration of a mixture of ropivacaine, a long acting local anesthetic,
ketorolac, a cyclooxygenase inhibitor (NSAID), and adrenalin around all structures
subject to surgical trauma inknee and hip arthroplasty.
Two patient cohorts of 40 patients scheduled for elective total knee arthroplasty
(TKA) and 15 patients scheduled for total hip arthroplasty (THA) contributed to the
work presented in this thesis. In a randomized trial the efficacy of LIA in TKA with
regard to pain at rest and upon movement was compared to femoral block. Both
methods result in a high quality pain relief and similar morphine consumption, but
fewer patients in the LIA group reported pain of 7/10 on any occasion during the 24 h
monitoring period (paper I).
In the same patient cohort the maximal total plasma concentration of ropivacaine was
below the established toxic threshold for most patients although a few reached
potentially toxic concentrations of 1.4-1.7 mg/L. The time to maximal detected
plasma concentration was around 4-6 h after release of tourniquet in TKA (paper II).
All patients in the THA cohort were subjected to the routine LIA protocol. In these
patients both the total and unbound plasma concentration of ropivacaine was
determined. The concentration was below the established toxic threshold. As
ropivacaine binds to a-1 acid glycoprotein(AAG) we assessed the possibility that
increased AAG may decrease the unbound concentration of ropivacaine. A40 %
increase in AAG was detected during the first 24 h after surgery, however the
fraction of unbound ropivacaine remained the same. There was a trend towards
increased C max of ropivacaine with increasing age and decreasing creatinine
clearance but the statistical power was too low to draw any conclusion (paper III).
Administration of 30mg ketorolac according to the LIA protocol both in TKA and
THA resulted in a similar Cmax as previously reported after 10 mg intramuscular
ketorolac (paper II, paper IV). Neither age, nor body weight or BMI, nor creatinine
clearance, correlates to maximal ketorolac plasma concentration or total exposure to
ketorolac (AUC) (paper IV).
In conclusion, LIA provides good postoperative analgesia which is similar to femoral
block after total knee arthroplasty. The plasma concentration of ropivacaine seems to
be below toxic levels in most TKA patients. The unbound plasma concentration of
ropivcaine in THA seems to be below the toxic level.
The use of ketorolac in LIA may not be safer than other routes of administration, and
similar restrictions should be applied in patients at risk of developing side effects
The crystal structure of human Rogdi provides insight into the causes of Kohlschutter-Tonz Syndrome
Kohlschutter-Tönz syndrome (KTS) is a rare autosomal-recessive disorder of childhood onset characterized by global developmental delay, spasticity, epilepsy, and amelogenesis imperfecta. Rogdi, an essential protein, is highly conserved across metazoans, and mutations in Rogdi are linked to KTS. However, how certain mutations in Rogdi abolish its physiological functions and cause KTS is not known. In this study, we determined the crystal structure of human Rogdi protein at atomic resolution. Rogdi forms a novel elongated curved structure comprising the ?? domain, a leucine-zipper-like four-helix bundle, and a characteristic ??-sheet domain. Within the ?? domain, the N-terminal H1 helix (residues 19-45) pairs with the C-terminal H6 helix (residues 252-287) in an antiparallel manner, indicating that the integrity of the four-helix bundle requires both N- and C-terminal residues. The crystal structure, in conjunction with biochemical data, indicates that the ?? domain might undergo a conformational change and provide a structural platform for protein-protein interactions. Disruption of the four-helix bundle by mutation results in significant destabilization of the structure. This study provides structural insights into how certain mutations in Rogdi affect its structure and cause KTS, which has important implications for the development of pharmaceutical agents against this debilitating neurological disease
Hyperphosphorylated tau in young and middle-aged subjects
The brain tissue obtained from ninety-five cognitively unimpaired subjects, with ages ranging from 22 to 50Β years upon death, were immunohistochemically assessed for neurodegenerative changes, i.e., hyperphosphorylated tau (HPΟ) and Ξ²-amyloid (AΞ²) pathology in predilection neuroanatomical areas. HPΟ pathology was observed in the transentorhinal cortex and/or the locus coeruleus (LC) in 33% of the subjects, without any obvious risk factors known to alter the microtubule-associated protein. HPΟ pathology was noted in the LC in 25 out of 83 subjects (30%), lacking concomitant cortical AΞ² or transentorhinal HPΟ pathology. This observation was present even when assessing only one routine section of 7Β ΞΌm thickness. The recent suggestion of prion-like propagation of neurodegeneration and the finding of neurodegeneration being quite common in middle-aged persons is alarming. It is noteworthy, however, that a substantial number of neurologically unimpaired subjects even at a very old age display only sparse to modest extent of neurodegenerative pathology. Thus, only a subset of subjects with neurodegenerative changes early in life seem to progress to a symptomatic disease with ageing. This observation brings forth the notion that other, yet unknown modifying factors influence the progression of degeneration that leads to a symptomatic disorder. The known association between alterations in the LC and mood disorders, and the finding of the LC being frequently affected with HPΟ pathology suggest that clinicopathological studies on young subjects both with or without mood disorders are warranted
Acute increase of alpha-synuclein inhibits synaptic vesicle recycling evoked during intense stimulation
This work was supported by grants from the NIH/National Institute
of Neurological Disorder and Stroke RO1 NS078165 (to J.R.M.),
the Morton Cure Paralysis Fund (to J.R.M.), and the Branfman Family
Foundation (to J.M.G.) and by a Dorothea Bennett graduate
fellowship (to D.J.B.)
Inositol Hexakisphosphate-Induced Autoprocessing of Large Bacterial Protein Toxins
Large bacterial protein toxins autotranslocate functional effector domains to the eukaryotic cell cytosol, resulting in alterations to cellular functions that ultimately benefit the infecting pathogen. Among these toxins, the clostridial glucosylating toxins (CGTs) produced by Gram-positive bacteria and the multifunctional-autoprocessing RTX (MARTX) toxins of Gram-negative bacteria have distinct mechanisms for effector translocation, but a shared mechanism of post-translocation autoprocessing that releases these functional domains from the large holotoxins. These toxins carry an embedded cysteine protease domain (CPD) that is activated for autoprocessing by binding inositol hexakisphosphate (InsP6), a molecule found exclusively in eukaryotic cells. Thus, InsP6-induced autoprocessing represents a unique mechanism for toxin effector delivery specifically within the target cell. This review summarizes recent studies of the structural and molecular events for activation of autoprocessing for both CGT and MARTX toxins, demonstrating both similar and potentially distinct aspects of autoprocessing among the toxins that utilize this method of activation and effector delivery
The Bifidobacterium dentium Bd1 Genome Sequence Reflects Its Genetic Adaptation to the Human Oral Cavity
Bifidobacteria, one of the relatively dominant components of the human intestinal microbiota, are considered one of the key groups of beneficial intestinal bacteria (probiotic bacteria). However, in addition to health-promoting taxa, the genus Bifidobacterium also includes Bifidobacterium dentium, an opportunistic cariogenic pathogen. The genetic basis for the ability of B. dentium to survive in the oral cavity and contribute to caries development is not understood. The genome of B. dentium Bd1, a strain isolated from dental caries, was sequenced to completion to uncover a single circular 2,636,368 base pair chromosome with 2,143 predicted open reading frames. Annotation of the genome sequence revealed multiple ways in which B. dentium has adapted to the oral environment through specialized nutrient acquisition, defences against antimicrobials, and gene products that increase fitness and competitiveness within the oral niche. B. dentium Bd1 was shown to metabolize a wide variety of carbohydrates, consistent with genome-based predictions, while colonization and persistence factors implicated in tissue adhesion, acid tolerance, and the metabolism of human saliva-derived compounds were also identified. Global transcriptome analysis demonstrated that many of the genes encoding these predicted traits are highly expressed under relevant physiological conditions. This is the first report to identify, through various genomic approaches, specific genetic adaptations of a Bifidobacterium taxon, Bifidobacterium dentium Bd1, to a lifestyle as a cariogenic microorganism in the oral cavity. In silico analysis and comparative genomic hybridization experiments clearly reveal a high level of genome conservation among various B. dentium strains. The data indicate that the genome of this opportunistic cariogen has evolved through a very limited number of horizontal gene acquisition events, highlighting the narrow boundaries that separate commensals from opportunistic pathogens
Genome Stability of Lyme Disease Spirochetes: Comparative Genomics of Borrelia burgdorferi Plasmids
Lyme disease is the most common tick-borne human illness in North America. In order to understand the molecular pathogenesis, natural diversity, population structure and epizootic spread of the North American Lyme agent, Borrelia burgdorferi sensu stricto, a much better understanding of the natural diversity of its genome will be required. Towards this end we present a comparative analysis of the nucleotide sequences of the numerous plasmids of B. burgdorferi isolates B31, N40, JD1 and 297. These strains were chosen because they include the three most commonly studied laboratory strains, and because they represent different major genetic lineages and so are informative regarding the genetic diversity and evolution of this organism. A unique feature of Borrelia genomes is that they carry a large number of linear and circular plasmids, and this work shows that strains N40, JD1, 297 and B31 carry related but non-identical sets of 16, 20, 19 and 21 plasmids, respectively, that comprise 33β40% of their genomes. We deduce that there are at least 28 plasmid compatibility types among the four strains. The B. burgdorferi βΌ900 Kbp linear chromosomes are evolutionarily exceptionally stable, except for a short β€20 Kbp plasmid-like section at the right end. A few of the plasmids, including the linear lp54 and circular cp26, are also very stable. We show here that the other plasmids, especially the linear ones, are considerably more variable. Nearly all of the linear plasmids have undergone one or more substantial inter-plasmid rearrangements since their last common ancestor. In spite of these rearrangements and differences in plasmid contents, the overall gene complement of the different isolates has remained relatively constant
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