Bladder Calculus Following an Unusual Vesical Foreign Body

Bladder calculus following vesical foreign bodies is uncommon. The usual presentation is presence of lower urinary symptoms. Most of these foreign bodies are either left inadvertently after open bladder operations or migrate from adjacent structures. This is a case report of an unusual self inserted foreign body in a female presenting with bladder calculus and diverticulum. Self inserted foreign body, particularly in females, is one of the important causes of bladder stones. Foreign body in the bladder should be suspected in a female patient with chronic lower urinary tract symptoms even in the absence of trauma or intervention Key Words: Urinary Bladder, Calculus, Foreign bod

Asymptotic behaviour of estimators of the parameters of nearly unstable INAR(1) models

A sequence of first-order integer-valued autoregressive type (INAR(1)) processes is investigated, where the autoregressive type coefficients converge to 1. It is shown that the limiting distribution of the joint conditional least squares estimators for this coefficient and for the mean of the innovation is normal. Consequences for sequences of Galton{Watson branching processes with unobservable immigration, where the mean of the offspring distribution converges to 1 (which is the critical value), are discussed

Calcite surface structure and reactivity: molecular dynamics simulations and macroscopic surface modelling of the calcite-water interface

Calcite–water interactions are important not only in carbon sequestration and the global carbon cycle, but also in contaminant behaviour in calcite-bearing host rock and in many industrial applications. Here we quantify the effect of variations in surface structure on calcite surface reactivity. Firstly, we employ classical Molecular Dynamics simulations of calcite surfaces containing an etch pit and a growth terrace, to show that the local environment in water around structurally different surface sites is distinct. In addition to observing the expected formation of more calcium–water interactions and hydrogen-bonds at lower-coordinated sites, we also observed subtle differences in hydrogen bonding around acute versus obtuse edges and corners. We subsequently used this information to refine the protonation constants for the calcite surface sites, according to the Charge Distribution MUltiSite Ion Complexation (CD-MUSIC) approach. The subtle differences in hydrogen bonding translate into markedly different charging behaviour versus pH, in particular for acute versus obtuse corner sites. The results show quantitatively that calcite surface reactivity is directly related to surface topography. The information obtained in this study is not only crucial for the improvement of existing macroscopic surface models of the reactivity of calcite towards contaminants, but also improves our atomic-level understanding of mineral–water interactions

A computational study of the interaction of organic surfactants with goethite alpha-FeO(OH) surfaces

We have studied the adsorption of three organic molecules onto different surfaces of goethite α-FeO(OH) using atomistic simulation techniques. New interatomic potentials for the interaction between goethite and the organic molecules were developed. In the majority of cases the organic molecules were found to be capable of forming a coordinate bond via their carbonyl oxygen atom with a surface iron ion. In addition, weaker hydrogen bonds were formed between the organic molecules and the surfaces. The largest adsorption energies were obtained for the modes of adsorption where the organic molecules bridged or spanned the periodic grooves or dips present on the goethite surfaces, thus forming several interactions between the molecule and the surface. Among all adsorbates studied, the hydroxamic acid molecule in the eclipsed conformation releases the largest adsorption energy when it interacts with goethite surfaces, followed by the staggered conformations of hydroxyethanal and methanoic acid molecules. The adsorption energies are in the range of −60.0 to −186.4 kJ mol−1. Due to the surface structure, as well as the flexibility and size of hydroxamic acid and hydroxyethanal, in most cases these adsorbate molecules lose their planarity with respect to the structure of the isolated molecules. We found that the replacement of pre-adsorbed water by the organic adsorbates is an exothermic process on all the goethite surfaces studied. The removal by sorption onto iron particles of humic and fulvic acids, the major substituents of natural organic matter (NOM) that pollutes aquifers and soils, is corroborated by our calculations of the adsorption of surfactants with the same functional groups as the surfaces of oxidised iron particles

Retrospective harm benefit analysis of pre-clinical animal research for six treatment interventions

The harm benefit analysis (HBA) is the cornerstone of animal research regulation and is considered to be a key ethical safeguard for animals. The HBA involves weighing the anticipated benefits of animal research against its predicted harms to animals but there are doubts about how objective and accountable this process is.i. To explore the harms to animals involved in pre-clinical animal studies and to assess these against the benefits for humans accruing from these studies; ii. To test the feasibility of conducting this type of retrospective HBA.Data on harms were systematically extracted from a sample of pre-clinical animal studies whose clinical relevance had already been investigated by comparing systematic reviews of the animal studies with systematic reviews of human studies for the same interventions (antifibrinolytics for haemorrhage, bisphosphonates for osteoporosis, corticosteroids for brain injury, Tirilazad for stroke, antenatal corticosteroids for neonatal respiratory distress and thrombolytics for stroke). Clinical relevance was also explored in terms of current clinical practice. Harms were categorised for severity using an expert panel. The quality of the research and its impact were considered. Bateson's Cube was used to conduct the HBA.The most common assessment of animal harms by the expert panel was 'severe'. Reported use of analgesia was rare and some animals (including most neonates) endured significant procedures with no, or only light, anaesthesia reported. Some animals suffered iatrogenic harms. Many were kept alive for long periods post-experimentally but only 1% of studies reported post-operative care. A third of studies reported that some animals died prior to endpoints. All the studies were of poor quality. Having weighed the actual harms to animals against the actual clinical benefits accruing from these studies, and taking into account the quality of the research and its impact, less than 7% of the studies were permissible according to Bateson's Cube: only the moderate bisphosphonate studies appeared to minimise harms to animals whilst being associated with benefit for humans.This is the first time the accountability of the HBA has been systematically explored across a range of pre-clinical animal studies. The regulatory systems in place when these studies were conducted failed to safeguard animals from severe suffering or to ensure that only beneficial, scientifically rigorous research was conducted. Our findings indicate a pressing need to: i. review regulations, particularly those that permit animals to suffer severe harms; ii. reform the processes of prospectively assessing pre-clinical animal studies to make them fit for purpose; and iii. systematically evaluate the benefits of pre-clinical animal research to permit a more realistic assessment of its likely future benefits

Effects of hydraulic retention time and bioflocculant addition on membrane fouling in a sponge-submerged membrane bioreactor

© 2016 Elsevier Ltd. The characteristics of activated sludge and membrane fouling were evaluated in a sponge-submerged membrane bioreactor (SSMBR) at different hydraulic retention times (HRTs) (6.67, 5.33 and 4.00 h). At shorter HRT, more obvious membrane fouling was caused by exacerbated cake layer formation and aggravated pore blocking. Activated sludge possessed more extracellular polymeric substances (EPS) due to excessive growth of biomass and lower protein to polysaccharide ratio in soluble microbial products (SMP). The cake layer resistance was aggravated by increased sludge viscosity together with the accumulated EPS and biopolymer clusters (BPC) on membrane surface. However, SMP showed marginal effect on membrane fouling when SSMBRs were operated at all HRTs. The SSMBR with Gemfloc® addition at the optimum HRT of 6.67 h demonstrated superior sludge characteristics such as larger floc size, less SMP in mixed liquor with higher protein/polysaccharide ratio, less SMP and BPC in cake layer, thereby further preventing membrane fouling

Thiol-capped gold nanoparticles swell-encapsulated into polyurethane as powerful antibacterial surfaces under dark and light conditions

A simple procedure to develop antibacterial surfaces using thiol-capped gold nanoparticles (AuNPs) is shown, which effectively kill bacteria under dark and light conditions. The effect of AuNP size and concentration on photo-activated antibacterial surfaces is reported and we show significant size effects, as well as bactericidal activity with crystal violet (CV) coated polyurethane. These materials have been proven to be powerful antibacterial surfaces against both Gram-positive and Gram-negative bacteria. AuNPs of 2, 3 or 5 nm diameter were swell-encapsulated into PU before a coating of CV was applied (known as PU-AuNPs-CV). The antibacterial activity of PU-AuNPs-CV samples was tested against Staphylococcus aureus and Escherichia coli as representative Gram-positive and Gram-negative bacteria under dark and light conditions. All light conditions in this study simulated a typical white-light hospital environment. This work demonstrates that the antibacterial activity of PU-AuNPs-CV samples and the synergistic enhancement of photoactivity of triarylmethane type dyes is highly dependent on nanoparticle size and concentration. The most powerful PU-AuNPs-CV antibacterial surfaces were achieved using 1.0 mg mL−1 swell encapsulation concentrations of 2 nm AuNPs. After two hours, Gram-positive and Gram-negative bacteria were reduced to below the detection limit (>4 log) under dark and light conditions

The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin motifs) family

The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin motifs) enzymes are secreted, multi-domain matrix-associated zinc metalloendopeptidases that have diverse roles in tissue morphogenesis and patho-physiological remodeling, in inflammation and in vascular biology. The human family includes 19 members that can be sub-grouped on the basis of their known substrates, namely the aggrecanases or proteoglycanases (ADAMTS1, 4, 5, 8, 9, 15 and 20), the procollagen N-propeptidases (ADAMTS2, 3 and 14), the cartilage oligomeric matrix protein-cleaving enzymes (ADAMTS7 and 12), the von-Willebrand Factor proteinase (ADAMTS13) and a group of orphan enzymes (ADAMTS6, 10, 16, 17, 18 and 19). Control of the structure and function of the extracellular matrix (ECM) is a central theme of the biology of the ADAMTS, as exemplified by the actions of the procollagen-N-propeptidases in collagen fibril assembly and of the aggrecanases in the cleavage or modification of ECM proteoglycans. Defects in certain family members give rise to inherited genetic disorders, while the aberrant expression or function of others is associated with arthritis, cancer and cardiovascular disease. In particular, ADAMTS4 and 5 have emerged as therapeutic targets in arthritis. Multiple ADAMTSs from different sub-groupings exert either positive or negative effects on tumorigenesis and metastasis, with both metalloproteinase-dependent and -independent actions known to occur. The basic ADAMTS structure comprises a metalloproteinase catalytic domain and a carboxy-terminal ancillary domain, the latter determining substrate specificity and the localization of the protease and its interaction partners; ancillary domains probably also have independent biological functions. Focusing primarily on the aggrecanases and proteoglycanases, this review provides a perspective on the evolution of the ADAMTS family, their links with developmental and disease mechanisms, and key questions for the future