Burkholderia multivorans survival and trafficking within macrophages

Cystic fibrosis (CF) patients are at great risk of opportunistic lung infection, particularly by members of the Burkholderia cepacia complex (Bcc). This group of bacteria can cause damage to the lung tissue of infected patients and are very difficult to eradicate due to their high levels of antibiotic resistance. Though the highly virulent B. cenocepacia has been the focus of virulence research for the past decade, B. multivorans is emerging as the most prevalent Bcc species infecting CF patients in North America. Despite several studies detailing the intramacrophage trafficking and survival of B. cenocepacia, no such data exists for B. multivorans. Our results demonstrated that clinical CF isolates, C5568 and C0514, and an environmental B. multivorans isolate, ATCC17616, were able to replicate and survive within murine macrophages in a manner similar to B. cenocepacia K56-2. These strains were also able to survive but were unable to replicate within human THP-1 macrophages. Differences in macrophage uptake were observed among all three B. multivorans strains; these variances were attributed to major differences in O-antigen production. Unlike B. cenocepacia-containing vacuoles, which delay phagosomal maturation in murine macrophages by 6 h, all B. multivorans containing vacuoles co-localized with late endosome/lysosomal marker LAMP-1 and the lysosomal marker dextran within 2 h of uptake. Together, these results indicate that while both Bcc species are able to survive and replicate within macrophages, they utilize different intramacrophage survival strategies. To observe differences in virulence the strains were compared using the Galleria mellonella model. When compared to the B. multivorans strains tested, B. cenocepacia K56-2 is highly virulent in this model and killed all worms within 24 h when injected at 107 CFU. B. multivorans clinical isolates C5568 and C0514 were significantly more virulent than the soil isolate ATCC17616, which was avirulent, even when worms were injected with 107 CFU. These results suggest strain differences in the virulence of B. multivorans isolates.

Evidence for a non-replicative intracellular stage of nontypable Haemophilus influenzae in epithelial cells

Nontypable Haemophilus influenzae (NTHi) is a Gram-negative, non-capsulated human bacterial pathogen, a major cause of a repertoire of respiratory infections, and intimately associated with persistent lung bacterial colonization in patients suffering from chronic obstructive pulmonary disease (COPD). Despite its medical relevance, relatively little is known about its mechanisms of pathogenicity. In this study, we found that NTHi invades the airway epithelium by a distinct mechanism, requiring microtubule assembly, lipid rafts integrity, and activation of phosphatidylinositol 3-kinase (PI3K) signalling. We found that the majority of intracellular bacteria are located inside an acidic subcellular compartment, in a metabolically active and non-proliferative state. This NTHi-containing vacuole (NTHi-CV) is endowed with late endosome features, co-localizing with LysoTracker, lamp-1, lamp-2, CD63 and Rab7. The NTHi-CV does not acquire Golgi- or autophagy-related markers. These observations were extended to immortalized and primary human airway epithelial cells. By using NTHi clinical isolates expressing different amounts of phosphocholine (PCho), a major modification of NTHi lipooligosaccharide, on their surfaces, and an isogenic lic1BC mutant strain lacking PCho, we showed that PCho is not responsible for NTHi intracellular location. In sum, this study indicates that NTHi can survive inside airway epithelial cells.

Primary cysts of the iris pigment epithelium. Clinical features and natural course in 234 patients

Objective: To describe the clinical characteristics, natural course, and complications of a large group of patients with primary iris pigment epithelium (IPE) cysts. Design: Observational case series. Participants: Two hundred thirty-four patients with primary IPE cysts participated. Results: Primary IPE cysts were classified as central in 6 patients (3%), midzonal in 50 patients (21%), peripheral in 170 patients (73%), and dislodged in 8 patients (3%). Central (pupillary) IPE cysts were found only in males, peripheral IPE cysts were found most often in females (69%), and no gender predilection was detected for midzonal and dislodged IPE cysts. Central and peripheral IPE cysts occurred in young patients (mean age, 20 and 33 years, respectively), whereas midzonal and dislodged IPE cysts were seen in slightly older patients (mean age, 52 and 45 years, respectively). Central IPE cysts were visible when the pupil was not dilated and appeared most often as a round or collapsed brown lesion arising from the pupillary margin, most commonly superonasally. Midzonal IPE cysts were brown and fusiform, best visualized after pupillary dilation. Peripheral IPE cysts produced a characteristic bulging in the iris stroma near the iris root, but they were directly visible in only 78% of cases. After wide dilation and patient and slit-lamp positioning, they appeared as a round clear lesion behind the iris, most often in the inferotemporal quadrant. Finally, dislodged IPE cysts appeared as a brown oval lesion, free floating in the anterior chamber (12%) or in the vitreous (12%), or fixed in the anterior chamber angle (75%). One hundred twenty-four patients (53%) were followed for a mean of 35 months (range, 3 months-19 years). In these patients, complications associated with IPE cysts included lens subluxation in one case (1%), iritis in one case (1%), focal cataract in two cases (2%), glaucoma in two cases (2%), and corneal touch in five cases (4%). Conclusion: Primary IPE cysts have characteristic clinical features that serve to differentiate them from intraocular malignancies. Most cysts have a benign clinical course, and treatment is rarely necessary.

Diabetic-like loss of corneal sensitivity in the 50% galactose fed rat is ameliorated with topical administration of an aldose reductase inhibitor

Purpose: To investigate the temporal course of corneal sensitivity loss & the role of aldose reductase inhibitors (ARI) in an animal model of diabetic ocular complications. Methods: Weanling male S-D rats were randomly grouped to received ad libitum water & diet consisting of Purina (#5001) w/ either: 50% starch (CON,n=15) or 50% D-galactose (GAL,n=30). Half the galactosemic rats (ARI,n=15) received topical 0.25% CT-112 (3x daily, 20µl, Senju Pharmaceutical Co., Japan). Control & remaining half of the galactosemic animals received equivalent doses of saline eyedrops. Rats were restrained w/o medication during sensitivity measurements conducted w/ a Cochet-Bonnet Aesthesiometer mounted on a micromanipulator. The end of the filament (0.012mm dia.), which applied a mean pressure of 0.96 g/mm perpendicular to the corneal surface at center, was in the plane of focus of a slit-lamp biomicroscope. Measurements were conducted by two investigators which were masked to the treatment group. The average blink-responses from 10 consecutive stimuli to each cornea were expressed as a percent. Results: Mean (±SD) baseline corneal sensitivity in all groups were similar (CON 73%±11, GAL 71%±15, ARI 74%±16). Corneal sensitivity in the galactosemic rat was decreased (p

Autologous limbal transplantation in patients with unilateral corneal stem cell deficiency

Aim - To describe a surgical technique for autologous limbal stem cell transplantation and the outcome of a series of patients with unilateral stem cell deficiency. Methods - A report of six consecutive patients who underwent autologous limbal stem cell transplantation is presented. The primary diagnosis included alkali burn (n = 3), conjunctival intraepithelial neoplasia (CIN) (n = 1), recurrent pterygium (n = 1), and contact lens induced keratopathy (n = 1). The autologous transplanted tissue consisted of peripheral cornea, limbus, and conjunctiva obtained from the contralateral eye. Three of the above patients underwent penetrating keratoplasty in association with autolimbal transplantation. A significant modification to established techniques was the close monitoring of conjunctival epithelial migration in the immediate postoperative period. If conjunctival epithelium threatened to migrate on to the corneal surface, it was mechanically removed at the slit lamp and prevented from crossing the limbus. This was required in three patients. Results - The mean follow up was 18.8 months. The outcome was satisfactory in all cases: a stable corneal surface was restored and there was a substantial improvement in vision and symptoms. One patient had a primary failure of the corneal allograft associated with glaucoma, and 6 months later developed a retinal detachment. No complications were noted in the donor eye with the exception of one patient who developed filamentary keratitis along the edge of the donor site. Conclusion - Autologous limbal transplantation with corneal, limbal, and conjunctival carriers was found to be useful for ocular surface reconstruction, over a mid-term follow up, in patients with unilateral stem cell deficiency. Close monitoring of the migration of conjunctival epithelium in the immediate postoperative period, and preventing it from crossing the limbus, ensured that the corneal surface was re-epithelialised exclusively from epithelial cells derived from the transplanted limbal tissue. This approach should improve the success of this procedure.

Agreement between clinical and ultrasound biomicroscopy findings in different types of glaucoma

Purpose. To evaluate agreement between clinical examination (slit lamp examination and gonioscopy) and ultrasound biomicroscopy (UBM) in characterizing various features of the anterior chamber angle and adjacent structures. Methods. Twenty-eight patients (51 eyes) with open angle glaucoma (14), closed angle glaucoma (4), narrow angle and/or plateau iris (10), who had undergone UBM between March 94 and September 95 were studied. Evaluated parameters included angle width, iris configuration and presence of angle closure. The UBMs were reviewed in a masked fashion. Results. In 87.8% of cases there was agreement (within 10 degrees) between gonioscopic and UBM estimates of angle width. In all cases with greater than 10 degrees difference (12.2%) the angle size estimated by UBM was less than that estimated clinically. Iris configuration was graded identically in 51% of cases; the majority of disagreements (76.1%) occurred in cases graded as "regular" by gonioscopy and as "steep" by UBM. Angle closure was judged to be present more frequently by UBM. Conclusions. UBM and gonioscopy do not necessarily yield identical values for angle width, iris configuration, and presence of angle closure.

Impact of Testing Procedure on Permeability of Compacted Soils

The commonly used British Standard constant head triaxial permeability (BS) test, for permeability testing of fine grained soils, is known to have a relatively long test duration. Consequently, a reduction in the required time for permeability test provides potential cost savings, to the construction industry (specifically, for use during Construction Quality Control (CQA) of landfill mineral liners). The purpose of this article is to investigate and evaluate alternative short duration testing methods for the measurement of the permeability of fine grained soils.

As part of the investigation the feasibility of an existing method of short duration permeability test, known as the Accelerated Permeability (AP) test was assessed and compared with permeability measured using British Standard method (BS) and Ramp Accelerated Permeability (RAP). Four different fine grained materials, of a variety of physical properties were compacted at various moisture contents to produced analogous samples for testing using three the three different methodologies. Fabric analysis was carried out on specimens derived from post-test samples using Mercury Intrusion Porosimetry (MIP) and Scanning Electron Microscope (SEM) to assess the effects of testing methodology on soil structure. Results showed that AP testing in general under predicts permeability values derived from the BS test due to large changes in structure of the soil caused by AP test methodology, which is also validated using MIP and SEM observations. RAP testing, in general provides an improvement to the AP test but still under-predicts permeability values. The potential savings in test duration are shown to be relatively minimal for both the AP and RAP tests.

Process for removing metals from hydrocarbons

The present invention relates to a process for the removal of mercury from a mercury- containing hydrocarbon fluid feed using specifically selected ionic liquids comprising, contacting the mercury-containing hydrocarbon fluid feed with an ionic liquid having the formula[Cat+][M+][X-] and separating from the ionic liquid a hydrocarbon fluid product having a reduced mercury content compared to the mercury-containing fluid feed.

Tailoring Plasmonic Metamaterials for DNA Molecular Logic Gates

Structural and functional information encoded in DNA combined with unique properties of nanomaterials could be of use for the construction of novel biocomputational circuits and intelligent biomedical nanodevices. However, at present their practical applications are still limited by either low reproducibility of fabrication, modest sensitivity, or complicated handling procedures. Here, we demonstrate the construction of label-free and switchable molecular logic gates that use specific conformation modulation of a guanine- and thymine- rich DNA, while the optical readout is enabled by the tunable alphabetical metamaterials, which serve as a substrate for surface enhanced Raman spectroscopy (MetaSERS). By computational and experimental investigations, we present a comprehensive solution to tailor the plasmonic responses of MetaSERS with respect to the metamaterial geometry, excitation energy, and polarization. Our tunable MetaSERS-based DNA logic is simple to operate, highly reproducible, and can be stimulated by ultra-low concentration of the external inputs, enabling an extremely sensitive detection of mercury ions.

Trimethylphenylammonium trichloromercurate(II), (Me3PhN)[HgCl3]

The crystal structure of (Me3PhN)[HgCl3] contains [(CH3)(3)(C6H5)N](+) cations and chains of distorted vertex-sharing [HgCl4](2-) tetrahedra running parallel to [100]. The tetrahedra around mercury(II) are distorted, exhibiting a [2+2] coordination. Apart from one of the Cl atoms, which is located on a twofold rotation axis, and a pair of symmetry-related methyl C atoms, which are located in general positions, all non H-atoms lie on mirror planes.

Bis(tetraethylammonium) octabromo-trimercurate(II), (Et4N)(2)[Hg3Br8]

The structure of (Et4N)(2)[Hg3Br8] contains isolated dinuclear [Hg2Br6](2-) anions and neutral HgBr2 molecules. Charge balance is achieved by ordered [Et4N](+) cations. The formula may therefore be written as (Et4N)(2)[Hg2Br6][HgBr2]. The N atoms of the (Et4N)(+) ions lie on a (4) over bar axis along [001] and, whereas one of the mercury(II) ions is placed on a mirror plane perpendicular to the c axis, the second one is located on a special position of site symmetry 2/m.

Arsenic Contents in Spanish Infant Rice, Pureed Infant Foods, and Rice

It seems there is a positive correlation between rice content and arsenic level in foods. This is of extraordinary importance for infants below 1 y of age because their diet is very limited and in some cases is highly dependent on rice-based products; this is particularly true for infants with the celiac disease because they have no other option than consume gluten-free products, such as rice or corn. Arsenic contents were significantly higher (P <0.001) in gluten-free infant rice (0.057 mg kg-1) than in products with gluten, based on a mixture of cereals (0.024 mg kg-1). Besides, especial precaution must be taken when preparing rice-based products at home, because arsenic content in Spanish rice was high, with levels being above 0.3 mg kg-1 in some cases.

Trace Element Abundance and Renal Disease

This research investigates the relationship between elevated trace elements in soils, stream sediments and stream water and the prevalence of Chronic Kidney Disease (CKD). The study uses a collaboration of datasets provided from the UK Renal Registry Report (UKRR) on patients with renal diseases requiring treatment including Renal Replacement Therapy (RRT), the soil geochemical dataset for Northern Ireland provided by the Tellus Survey, Geological Survey of Northern Ireland (GSNI) and the bioaccessibility of Potentially Toxic Elements (PTEs) from soil samples which were obtained from the Unified Barge Method (UBM). The relationship between these factors derives from the UKRR report which highlights incidence rates of renal impaired patients showing regional variation with cases of unknown aetiology. Studies suggest a potential cause of the large variation and uncertain aetiology is associated with underlying environmental factors such as the oral bioaccessibility of trace elements in the gastrointestinal tract.
As previous research indicates that long term exposure is related to environmental factors, Northern Ireland is ideally placed for this research as people traditionally live in the same location for long periods of time. Exploratory data analysis and multivariate analyses are used to examine the soil, stream sediments and stream water geochemistry data for a range of key elements including arsenic, lead, cadmium and mercury identified from a review of previous renal disease literature. The spatial prevalence of patients with long term CKD is analysed on an area basis. Further work includes cluster analysis to detect areas of low or high incidences of CKD that are significantly correlated in space, Geographical Weighted Regression (GWR) and Poisson kriging to examine locally varying relationship between elevated concentrations of PTEs and the prevalence of CKD.

Optical coherence tomography for the diagnosis of neovascular age-related macular degeneration: a systematic review

The purpose is to study the diagnostic performance of optical coherence tomography (OCT) and alternative diagnostic tests for neovascular age-related macular degeneration (nAMD). Methods employed are as follows:systematic review and meta-analysis; Index test: OCT including time-domain (TD-OCT) and the most recently developed spectral domain (SD-OCT); comparator tests: visual acuity, clinical evaluation (slit lamp), Amsler chart, colour fundus photographs, infra-red reflectance, red-free images/blue reflectance, fundus autofluorescence imaging (FAF), indocyanine green angiography (ICGA), preferential hyperacuity perimetry (PHP), and microperimetry; reference standard: fundus fluorescein angiography. Databases searched included MEDLINE, MEDLINE In Process, EMBASE, Biosis, SCI, the Cochrane Library, DARE, MEDION, and HTA database. Last literature searches: March 2013. Risk of bias assessed using QUADAS-2. Meta-analysis models were fitted using hierarchical summary receiver operating characteristic (HSROC) curves. Twenty-two studies (2 abstracts and 20 articles) enrolling 2124 participants were identified, reporting TD-OCT (12 studies), SD-OCT (1 study), ICGA (8 studies), PHP (3 studies), Amsler grid, colour fundus photography and FAF (1 study each). Most studies were considered to have a high risk of bias in the patient selection (55%, 11/20), and flow and timing (40%, 8/20) domains. In a meta-analysis of TD-OCT studies, sensitivity and specificity (95% CI) were 88% (46–98%) and 78% (64–88%), respectively. There was insufficient information to undertake meta-analysis for other tests. TD-OCT is a sensitive test for detecting nAMD, although specificity was only moderate. Data on SD-OCT are sparse. Diagnosis of nAMD should not rely solely on OCT.

Advanced Modelling and Optimization of Infared Oven in Injection Stretch Blow-moulding for Energy Saving

In the production process of polyethylene terephthalate (PET) bottles, the initial temperature of preforms plays a central role on the final thickness, intensity and other structural properties of the bottles. Also, the difference between inside and outside temperature profiles could make a significant impact on the final product quality. The preforms are preheated by infrared heating oven system which is often an open loop system and relies heavily on trial and error approach to adjust the lamp power settings. In this paper, a radial basis function (RBF) neural network model, optimized by a two-stage selection (TSS) algorithm combined with partial swarm optimization (PSO), is developed to model the nonlinear relations between the lamp power settings and the output temperature profile of PET bottles. Then an improved PSO method for lamp setting adjustment using the above model is presented. Simulation results based on experimental data confirm the effectiveness of the modelling and optimization method.