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Xylella fastidiosa (Xf) is the causative agent of Pierce's disease in a variety of commercially important plants such as citrus, coffee, and grapes. By blocking the xylem, Xf disrupts water and nutrient transport. Xf is a gram-negative phytopathogen that can form biofilms. Twelve genes have been identified in Xf that can regulate exopolysaccharides, a major component of biofilms, including aconitase, which responds to intracellular iron levels. We have employed a quantitative assay for biofilm formation referred to as minimal biofilm elimination concentration (MBEC) assay that is amenable for high-throughput screening. Biofilm formation by Xf (Napa, CA) can be blocked using iron chelators such as lactoferrin (LF), ethylenediaminetetraacetic acid (EDTA), and S,S' -ethylenediaminedisuccinic acid (EDDS). Incubation of Xf in the presence of LF at 1000 microg/mL for 3.5 days showed inhibition of biofilm formation (42%) as well as inhibition (32%) of planktonic growth (liquid-phase bacteria). EDTA at a concentration of 15mg/mL inhibited 99.7% of biofilm formation and 98.9% of planktonic growth in a 24h incubation. In contrast, EDDS at a concentration of 38.2mg/mL showed 64.7% inhibition of biofilm formation and 33.6% inhibition of planktonic growth. Iron deprivation could serve as a first step toward eradication of Pierce's disease via blockage of biofilm formation. [ABSTRACT FROM AUTHOR]

Stratified coatings are used to provide properties at a surface, such as hardness or refractive index, which are different from underlying layers. Although time-savings are offered by self-assembly approaches, there have been no methods yet reported to offer stratification on demand. Here, we demonstrate a strategy to create self-assembled stratified coatings, which can be switched to homogeneous structures when required. We use blends of large and small colloidal polymer particle dispersions in water that self-assemble during drying because of an osmotic pressure gradient that leads to a downward velocity of larger particles. Our confocal fluorescent microscopy images reveal a distinct surface layer created by the small particles. When the pH of the initial dispersion is raised, the hydrophilic shells of the small particles swell substantially, and the stratification is switched off. Brownian dynamics simulations explain the suppression of stratification when the small particles are swollen as a result of reduced particle mobility, a drop in the pressure gradient, and less time available before particle jamming. Our strategy paves the way for applications in antireflection films and protective coatings in which the required surface composition can be achieved on demand, simply by adjusting the pH prior to deposition.

We present a fundamental study into the self-assembly of (cyclic peptide)-polymer conjugates as a versatile supramolecular motif to engineer nanotubes with defined structure and dimensions, as characterised in solution using small-angle neutron scattering (SANS). This work demonstrates the ability of the grafted polymer to stabilise and/or promote the formation of unaggregated nanotubes by the direct comparison to the unconjugated cyclic peptide precursor. This ideal case permitted a further study into the growth mechanism of self-assembling cyclic peptides, allowing an estimation of the cooperativity. Furthermore, we show the dependency of the nanostructure on the polymer and peptide chemical functionality in solvent mixtures that vary in the ability to compete with the intermolecular associations between cyclic peptides and ability to solvate the polymer shell., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background and Objectives: Salivary biomarkers may enhance diagnostic sensitivity for peri-implant disease assessment. This study aimed to investigate the association of salivary periodontopathogen count and salivary interleukin-1beta (IL-1β) level with the peri-implant crevicular fluid IL-1β response at peri-implant mucositis (PM) sites among subjects with differing periodontal disease susceptibility., Materials and Methods: Eighty-seven partially edentulous subjects having at least one implant with peri-implant mucositis were included: 40 with history of chronic periodontitis (P) and 47 with no history of periodontitis (NP). Salivary IL-1β, peri-implant crevicular fluid (PICF) IL-1β, and salivary red complex pathogen counts were recorded. Subjects were scored according to a threshold salivary pathogen level of more than 5log (10) counts and assigned a "red complex score." Quartiles of salivary and PICF IL-1β levels were also scored. Area under receiver operating curve (AUC) was computed to predict the highest PICF IL-1β score using salivary biomarker as predictors and age-adjusted logistic regression performed for the significant predictors., Results: In the NP group, red complex score (AUC = 0.758 P = 0.010) (odds ratio = 1.377) and salivary IL-1β (AUC = 0.708 P = 0.038) (odds ratio = 2.506) were significant predictors of highest PICF IL-1β quartile score. In the P group, no significant associations were noted., Conclusions: Salivary biomarkers could distinguish the "high" pro-inflammatory responders at PM sites only in subjects without inherent periodontal disease susceptibility. Periodontal susceptibility may impact the immuno-inflammatory response in sub-peri-implant niches of those with peri-implant mucositis., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

We report the synthesis and assembly of (N-methylated cyclic peptide)-polymer conjugates for which the cyclic peptide is attached to either the α- or both α- and ω- end groups of a polymer. A combination of chromatographic, spectroscopic, and scattering techniques reveals that the assembly of the conjugates follows a two-level hierarchy, initially driven by H-bond formation between two N-methylated cyclic peptides, followed by unspecific, noncovalent aggregation of this peptide into small domains that behave as branching points and lead to the formation of branched supramolecular polymers.

β-Sheet forming self assembling cyclic peptides offer a versatile scaffold for the construction and control of hydrogen-bonded nanotube assemblies. These structures have major advantages over other nanoscale tubular structures, including sub-nanometer control over the internal diameter, and the ability to control internal and external chemical functionality. This Tutorial Review presents an overview of nanotubes derived from this class of cyclic peptides. The design rationale for functional nanotubes based on cyclic peptide ring size and chemical functionality is discussed. Additionally, we highlight the recent expansion of the nanotube toolbox through conjugation of (macro)molecules to the cyclic peptides. These provide additional functionality and control nanotube dimensions that could potentially prove beneficial in future applications.

Breakthrough pain (BKP) is a transitory flare of pain that occurs on a background of relatively well controlled baseline pain. Previous surveys have found that BKP is highly prevalent among patients with cancer pain and predicts more severe pain, pain-related distress and functional impairment, and relatively poor quality of life. An international group of investigators assembled by a task force of the International Association for the Study of Pain (IASP) evaluated the prevalence and characteristics of BKP as part of a prospective, cross-sectional survey of cancer pain. Fifty-eight clinicians in 24 countries evaluated a total of 1095 patients with cancer pain using patient-rated items from the Brief Pain Inventory (BPI) and observer-rated measures. The observer-rated information included demographic and tumor-related data, the occurrence of BKP, and responses on checklists of pain syndromes and pathophysiologies. The clinicians reported BKP in 64.8% of patients. Physicians from English-speaking countries were significantly more likely to report BKP than other physicians. BKP was associated with higher pain scores and functional interference on the BPI. Multivariate analysis showed an independent association of BKP with the presence of more than one pain, a vertebral pain syndrome, pain due to plexopathy, and English-speaking country. These data confirm the high prevalence of BKP, its association with more severe pain and functional impairment, and its relationship to specific cancer pain syndromes. Further studies are needed to characterize subtypes of BKP. The uneven distribution of BKP reporting across pain specialists from different countries suggests that more standardized methods for diagnosing BKP are needed.

A pregnant woman was comatose after a motor vehicle accident at 13 weeks' gestation. The nutritional needs of the patient were supported by tube feedings after percutaneous endoscopic gastrostomy. Clinical management was required for nutrition support, infection, and fetal development. At 37 weeks' gestation, a normal 3640-g male infant was delivered by cesarean section. This represents the first case report of a successful pregnancy outcome after percutaneous endoscopic gastrostomy for enteral nutrition support of a pregnant comatose patient.

The purpose of this article is to discuss and analyze the controversial treatment protocols that are currently recommended in the management of frontal sinus fractures. Embryology, anatomy, and diagnostic radiology of the frontal sinus are also discussed.

Dyskeratosis congenita is reported in two male Singaporean Chinese cousins. The family pedigree is presented. Lichen planus or lichenoid lesions, instead of leukoplakia, was the manifestation in the oral cavity. The mode of inheritance and the differential diagnosis of Fanconi's anaemia are discussed. Dental findings are emphasised as such information is lacking in previously reported cases. One of the subjects expired of aplastic anaemia, which together with oral malignancy, is one fatal complication of this disease.