617 research outputs found
Cancer therapeutic potential of combinatorial immuno- and vaso-modulatory interventions
Currently, most of the basic mechanisms governing tumor-immune system
interactions, in combination with modulations of tumor-associated vasculature,
are far from being completely understood. Here, we propose a mathematical model
of vascularized tumor growth, where the main novelty is the modeling of the
interplay between functional tumor vasculature and effector cell recruitment
dynamics. Parameters are calibrated on the basis of different in vivo
immunocompromised Rag1-/- and wild-type (WT) BALB/c murine tumor growth
experiments. The model analysis supports that tumor vasculature normalization
can be a plausible and effective strategy to treat cancer when combined with
appropriate immuno-stimulations. We find that improved levels of functional
tumor vasculature, potentially mediated by normalization or stress alleviation
strategies, can provide beneficial outcomes in terms of tumor burden reduction
and growth control. Normalization of tumor blood vessels opens a therapeutic
window of opportunity to augment the antitumor immune responses, as well as to
reduce the intratumoral immunosuppression and induced-hypoxia due to vascular
abnormalities. The potential success of normalizing tumor-associated
vasculature closely depends on the effector cell recruitment dynamics and tumor
sizes. Furthermore, an arbitrary increase of initial effector cell
concentration does not necessarily imply a better tumor control. We evidence
the existence of an optimal concentration range of effector cells for tumor
shrinkage. Based on these findings, we suggest a theory-driven therapeutic
proposal that optimally combines immuno- and vaso-modulatory interventions
Answer to the Letter to the Editor of C. Brembilla et al. concerning “Dynamic cervical myelopathy in young adults” by Hattou L, Morandi X, Le Reste PJ, et al: Eur Spine J 2014, 23:1515–22
The strictly conserved Cys76 plays a crucial role in the conformational stability of reduced Px III
Spectrometric Monitoring of Atmospheric Carbon Tetrafluoride (CF4) Above the Jungfraujoch Station Since 1989: Evidence of Continued Increase But at a Slowing Rate
The long-term evolution of the vertical column abundance of carbon tetrafluoride (CF4) above the high-altitude Jungfraujoch station (Swiss Alps, 46.5 ° N, 8.0 ° E, 3580 ma.s.l.) has been derived from the spectrometric analysis of Fourier transform infrared solar spectra recorded at that site between 1989 and 2012. The investigation is based on a multi-microwindow approach, two encompassing pairs of absorption lines belonging to the R-branch of the strong ν3 band of CF4 centered at 1283 cm-1, and two additional ones to optimally account for weak but overlapping HNO3 interferences. The analysis reveals a steady accumulation of the very long-lived CF4 above the Jungfraujoch at mean rates of (1.38 ± 0.11) x 1013 molec cm-2 yr-1 from 1989 to 1997, and (0.98 +/- 0.02) x 1013 molec cm-2 yr-1 from 1998 to 2012, which correspond to linear growth rates of 1.71 ± 0.14 and 1.04 ± 0.02% yr-1 respectively referenced to 1989 and 1998. Related global CF4 anthropogenic emissions required to sustain these mean increases correspond to 15.8 ±1.3 and 11.1 ± 0.2 Gg yr-1 over the above specified time intervals. Findings reported here are compared and discussed with respect to relevant northern mid-latitude results obtained remotely from space and balloons as well as in situ at the ground, including new gas chromatography mass spectrometry measurements performed at the Jungfraujoch since 2010
Management of swallowing disorders in ICU patients - A multinational expert opinion.
BACKGROUND
Dysphagia is common in intensive care unit (ICU) patients, yet it remains underrecognized and often unmanaged despite being associated with life-threatening complications, prolonged ICU stays and hospitalization.
PURPOSE
To propose an expert opinion for the diagnosis and management of dysphagia developed from evidence-based clinical recommendations and practitioner insights.
METHODS
A multinational group of dysphagia and critical care experts conducted a literature review using a modified ACCORD methodology. Based on a fusion of the available evidence and the panel's clinical experience, an expert opinion on best practice management was developed.
RESULTS
The panel recommends adopting clinical algorithms intended to promote standardized, high-quality care that triggers timely systematic dysphagia screening, assessment, and treatment of extubated and tracheostomized patients in the ICU.
CONCLUSIONS
Given the lack of robust scientific evidence, two clinical management algorithms are proposed for use by multidisciplinary teams to improve early systematic detection and effective management of dysphagia in ICU patients. Additionally, emerging therapeutic options such as neurostimulation have the potential to improve the quality of ICU dysphagia care
Association Study of TRPC4 as a Candidate Gene for Generalized Epilepsy with Photosensitivity
Photoparoxysmal response (PPR) is characterized by abnormal visual sensitivity of the brain to photic stimulation. Frequently associated with idiopathic generalized epilepsies (IGEs), it might be an endophenotype for cortical excitability. Transient receptor potential cation (TRPC) channels are involved in the generation of epileptiform discharges, and TRPC4 constitutes the main TRPC channel in the central nervous system. The present study investigated an association of PPR with sequence variations of the TRPC4 gene. Thirty-five single nucleotide polymorphisms (SNP) within TRPC4 were genotyped in 273 PPR probands and 599 population controls. Association analyses were performed for the broad PPR endophenotype (PPR types I-IV; n = 273), a narrow model of affectedness (PPR types III and IV; n = 214) and PPR associated with IGE (PPR/IGE; n = 106) for each SNP and for corresponding haplotypes. Association was found between the intron 5 SNP rs10507456 and PPR/IGE both for single markers (P = 0.005) and haplotype level (P = 0.01). Three additional SNPs (rs1535775, rs10161932 and rs7338118) within the same haplotype block were associated with PPR/IGE at P < 0.05 (uncorrected) as well as two more markers (rs10507457, rs7329459) located in intron 3. Again, the corresponding haplotype also showed association with PPR/IGE. Results were not significant following correction for multiple comparisons by permutation analysis for single markers and Bonferroni-Holm for haplotypes. No association was found between variants in TRPC4 and other phenotypes. Our results showed a trend toward association of TRPC4 variants and PPR/IGE. Further studies including larger samples of photosensitive probands are required to clarify the relevance of TRPC4 for PPR and IGE
Helical stability of the GnTV transmembrane domain impacts on SPPL3 dependent cleavage
Signal-Peptide Peptidase Like-3 (SPPL3) is an intramembrane cleaving aspartyl protease that causes secretion of extracellular domains from type-II transmembrane proteins. Numerous Golgi-localized glycosidases and glucosyltransferases have been identified as physiological SPPL3 substrates. By SPPL3 dependent processing, glycan-transferring enzymes are deactivated inside the cell, as their active site-containing domain is cleaved and secreted. Thus, SPPL3 impacts on glycan patterns of many cellular and secreted proteins and can regulate protein glycosylation. However, the characteristics that make a substrate a favourable candidate for SPPL3-dependent cleavage remain unknown. To gain insights into substrate requirements, we investigated the function of a GxxxG motif located in the transmembrane domain of N-acetylglucosaminyltransferase V (GnTV), a well-known SPPL3 substrate. SPPL3-dependent secretion of the substrate’s ectodomain was affected by mutations disrupting the GxxxG motif. Using deuterium/hydrogen exchange and NMR spectroscopy, we studied the effect of these mutations on the helix flexibility of the GnTV transmembrane domain and observed that increased flexibility facilitates SPPL3-dependent shedding and vice versa. This study provides first insights into the characteristics of SPPL3 substrates, combining molecular biology, biochemistry, and biophysical techniques and its results will provide the basis for better understanding the characteristics of SPPL3 substrates with implications for the substrates of other intramembrane proteases
Structural investigations of the heterotetrameric E5/PDGF-receptor β complex by oriented circular dichroism and solid state NMR
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