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In vitro and in vivo modification of Neisseria gonorrhoeae lipooligosaccharide epitope structure by sialylation.
After growth of gonococci in the presence of cytidine monophospho-N-acetyl-neuraminic acid (CMP-NANA), their 4.5-kD lipooligosaccharide (LOS) component was increased by approximately 400 daltons, whereas the LOS of strains lacking the 4.5-kD component were unaffected. Expression of mAb-defined epitopes on the 4.5-kD component was decreased on LOS of strains grown in CMP-NANA, and treatment of the LOS with neuraminidase reversed this affect. Gonococci incubated with human PMNs also had decreased expression of the 4.5-kD+ epitopes. A detergent extract of gonococci incorporated radiolabeled NANA in the LOS, suggesting the presence of a sialyltransferase in gonococci. Exogenous sialyltransferases also could use LOS as an acceptor
Evolution of tetraspanin antigens in the zoonotic Asian blood fluke Schistosoma japonicum
BACKGROUND: Despite successful control efforts in China over the past 60Â years, zoonotic schistosomiasis caused by Schistosoma japonicum remains a threat with transmission ongoing and the risk of localised resurgences prompting calls for a novel integrated control strategy, with an anti-schistosome vaccine as a core element. Anti-schistosome vaccine development and immunisation attempts in non-human mammalian host species, intended to interrupt transmission, and utilising various antigen targets, have yielded mixed success, with some studies highlighting variation in schistosome antigen coding genes (ACGs) as possible confounders of vaccine efficacy. Thus, robust selection of target ACGs, including assessment of their genetic diversity and antigenic variability, is paramount. Tetraspanins (TSPs), a family of tegument-surface antigens in schistosomes, interact directly with the host's immune system and are promising vaccine candidates. Here, for the first time to our knowledge, diversity in S. japonicum TSPs (SjTSPs) and the impact of diversifying selection and sequence variation on immunogenicity in these protiens were evaluated. METHODS: SjTSP sequences, representing parasite populations from seven provinces across China, were gathered by baiting published short-read NGS data and were analysed using in silico methods to measure sequence variation and selection pressures and predict the impact of selection on variation in antigen protein structure, function and antigenic propensity. RESULTS: Here, 27 SjTSPs were identified across three subfamilies, highlighting the diversity of TSPs in S. japonicum. Considerable variation was demonstrated for several SjTSPs between geographical regions/provinces, revealing that episodic, diversifying positive selection pressures promote amino acid variation/variability in the large extracellular loop (LEL) domain of certain SjTSPs. Accumulating polymorphisms in the LEL domain of SjTSP-2, -8 and -23 led to altered structural, functional and antibody binding characteristics, which are predicted to impact antibody recognition and possibly blunt the host's ability to respond to infection. Such changes, therefore, appear to represent a mechanism utilised by S. japonicum to evade the host's immune system. CONCLUSION: Whilst the genetic and antigenic geographic variability observed amongst certain SjTSPs could present challenges to vaccine development, here we demonstrate conservation amongst SjTSP-1, -13 and -14, revealing their likely improved utility as efficacious vaccine candidates. Importantly, our data highlight that robust evaluation of vaccine target variability in natural parasite populations should be a prerequisite for anti-schistosome vaccine development
Soil particle tracing using RFID tags for elucidating the behavior of radiocesium on bare soil surfaces in Fukushima
Australian Plate Subduction is Responsible for Northward Motion of the IndiaâAsia Collision Zone and âŒ1,000 km Lateral Migration of the Indian Slab
Health care experiences of Black cancer survivors: A qualitative study exploring drivers of low and high Consumer Assessment of Healthcare Providers and Systems global ratings of care
Background: The purpose of this study was to understand the experiences of Black patients with cancer in health care by comparing drivers of high and low ratings. / Methods: Semistructured in-depth interviews were conducted with 18 Black patients with cancer recruited from cancer survivorship support groups and Facebook between May 2019 and March 2020. Interviews were coded across all transcripts by using a thematic analysis approach before comparing low- and high-rating groups. / Results: There were three major themes that influenced whether patients rated their care as low or high, which included the patientâprovider relationship, health care staff interactions, and cancer care coordination. For example, the high-rating group described good communication with the health care team as physicians listening to their needs, being responsive to their concerns, and providing recommendations on how to address side effects. In contrast, the low-rating group described poor communication with their health care team as their needs being dismissed and being excluded from decision-making processes. Additionally, there were two distinct themes that influenced patientsâ low ratings: insurance and financial toxicity issues and experiences of health care discrimination. / Conclusions: In an effort to promote equitable cancer care experiences for Black patients, it is important that health systems work to prioritize patient interactions with health care providers and staff, comprehensive care management for patients with cancer, and reductions in the financial burden of caring for cancer
The importance of simulating changes in topography in process-based soil erosion modelling: Implications for landscape evolution modelling
Integrating novel field, laboratory and modelling techniques to upscale estimates of soil erosion
Structureâproperties relationships in fibre drawing of bioactive phosphate glasses
New bioactive phosphate glasses suitable for continuous fibre production are investigated in this work. The structure of both bulk and fibres from Na2OâCaOâMgOâP2O5 glasses has been studied by means of Raman and 31P and 23Na nuclear magnetic resonance spectroscopies, and the structural results have been correlated with the mechanical properties of the fibres and the dissolution rate of the bulk glasses. It has been observed that the mechanical properties of the phosphate glass fibres are influenced by the glass network connectivity, while the dissolution rates are governed by the Qi speciation of the PO4 units. As seen in previous studies, molar volume seems to play an important role in the fragility behaviour of phosphate glasses. Here, a lower molar volume resulting from the increase in the oxygen packing density hinders the cooperative flow of the PO4 units throughout the glass network and, therefore, causes a reduction in the kinetic fragility
Statistical analysis of human boy movement and group interactions in response to music
Quantification of time series that relate to physiological data is challenging for empirical music research. Up to now, most studies have focused on time-dependent responses of individual subjects in controlled environments. However, little is known about time-dependent responses of between-subject interactions in an ecological context. This paper provides new findings on the statistical analysis of group synchronicity in response to musical stimuli. Different statistical techniques were applied to time-dependent data obtained from an experiment on embodied listening in individual and group settings. Analysis of inter group synchronicity are described. Dynamic Time Warping (DTW) and Cross Correlation Function (CCF) were found to be valid methods to estimate group coherence of the resulting movements. It was found that synchronicity of movements between individuals (human human interactions) increases significantly in the social context. Moreover, Analysis of Variance (ANOVA) revealed that the type of music is the predominant factor in both the individual and the social context
Extended structures of polyiodide salts of transition metal macrocyclic complexes
The structures of five polyiodide salts, [Co([9]aneS3)2]I11 (1),
[Ni([9]aneS3)2]I6 (2), [Ni([9]aneS3)2]I10 (3), [Pd([12]aneS4)]I6
(4) and [Pd([14]aneS4)]I10#1;MeCN (5), containing the template
cations [Co([9]aneS3)2]3+, [Ni([9]aneS3)2]2+, [Pd([12]aneS4)]2+
and [Pd([14]aneS4)]2+ ([9]aneS3 = 1,4,7-trithiacyclononane,
[12]aneS4 = 1,4,7,10-tetrathiacyclododecane, [14]aneS4 =
1,4,8,11-tetrathiacyclotetradecane) exhibit a range of polyiodide
and polyanionic framework structures. In (1) the charge
on the CoIII cation is balanced by three I#2;
3 anions, which along
with a neutral di-iodine molecule form I3#2;
11 rings in an
extended structure comprising undulating chains of alternating
I3#2;
11 rings and complex cations. In (2) the complex cation
is linked to two tri-iodide anions by S#1; #1; #1;I interactions into well
separated sheets of cations and anions, while in (3), I#2;
5 anions
are linked by I#1; #1; #1;I interactions into helices which are crosslinked
by S#1; #1; #1;I contacts to form sheets. Rather longer I#1; #1; #1;I
contacts in (4) assemble I#2;
3 ions into 2 #3; 2 rods, which are
linked into a three-dimensional network by S#1; #1; #1;I contacts. In
(5) the N atom of the acetonitrile solvent molecule forms an
array of four weak CâH#1; #1; #1;N hydrogen bonds to the
macrocycle. The extended structure comprises corrugated
zigzag chains of polyiodide rings formed by linked I#2;
5 units; the
complex cations are attached to the polyiodide network by
S...I contacts, which link the chains to form layers
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