Aerodynamic and Electrostatic Properties of Model Dry Powder Aerosols: a Comprehensive Study of Formulation Factors

The impact of formulation variables on aerodynamic and electrostatic properties of dry powder aerosol particles is of great importance to the development of efficient and reproducible inhaler products. Systematic evaluation requires a well-designed series of experiments using appropriate methods. A factorial experimental design was employed. In broad terms, the conditions considered were two drugs, albuterol and budesonide, in combination with different excipients, drug concentrations, delivered doses, and metering system (capsule composition) and sampled under different flow conditions using standard entrainment tubes. Samples were collected in an electrical low-pressure impactor, to evaluate distribution of electrostatic properties, and an Andersen eight-stage nonviable cascade impactor, to estimate aerodynamic particle size distribution, concurrently. The deposition studies allowed calculation of approximate per particle charge levels for drug. The results showed very high particle charge levels, often in the 1,000–10,000 of elementary charges per particle range, orders of magnitude higher than charge levels predicted by the Boltzmann charge distribution. The charge levels are considerably higher than had previously been estimated (200e per particle).KEY WORDS: aerodynamics, aerosol(s), electrostatics, experimental design, formulation factors     

Characterization of a plant-produced recombinant human secretory IgA with broad neutralizing activity against HIV

Recombinant Secretory IgA (SIgA) complexes have the potential to improve antibody-based passive immunotherapeutic approaches to combat many mucosal pathogens. In this report, we describe the expression, purification and characterization of a human SIgA format of the broadly neutralizing anti-HIV monoclonal antibody (mAb) 2G12, using both transgenic tobacco plants and transient expression in Nicotiana benthamiana as expression hosts (P2G12 SIgA). The resulting heterodecameric complexes accumulated in intracellular compartments in leaf tissue, including the vacuole. SIgA complexes could not be detected in the apoplast. Maximum yields of antibody were 15.2 μg/g leaf fresh mass (LFM) in transgenic tobacco and 25 μg/g LFM after transient expression, and assembly of SIgA complexes was superior in transgenic tobacco. Protein L purified antibody specifically bound HIV gp140 and neutralised tier 2 and tier 3 HIV isolates. Glycoanalysis revealed predominantly high mannose structures present on most N-glycosylation sites, with limited evidence for complex glycosylation or processing to paucimannosidic forms. O-glycan structures were not identified. Functionally, P2G12 SIgA, but not IgG, effectively aggregated HIV virions. Binding of P2G12 SIgA was observed to CD209 / DC-SIGN, but not to CD89 / FcalphaR on a monocyte cell line. Furthermore, P2G12 SIgA demonstrated enhanced stability in mucosal secretions in comparison to P2G12 IgG mAb.     

The British antibiotic and silver-impregnated catheters for ventriculoperitoneal shunts multi-centre randomised controlled trial (the BASICS trial): study protocol

Background

Insertion of a ventriculoperitoneal shunt (VPS) for the treatment of hydrocephalus is one of the most common neurosurgical procedures in the UK, but failures caused by infection occur in approximately 8% of primary cases. VPS infection is associated with considerable morbidity and mortality and its management results in substantial cost to the health service. Antibiotic-impregnated (rifampicin and clindamycin) and silver-impregnated VPS have been developed to reduce infection rates. Whilst there is some evidence showing that such devices may lead to a reduction in VPS infection, there are no randomised controlled trials (RCTs) to support their routine use.

Methods/design

Overall, 1,200 patients will be recruited from 17 regional neurosurgical units in the UK and Ireland. Patients of any age undergoing insertion of their first VPS are eligible. Patients with previous indwelling VPS, active and on-going cerebrospinal fluid (CSF) or peritoneal infection, multiloculated hydrocephalus requiring multiple VPS or neuroendoscopy, and ventriculoatrial or ventriculopleural shunt planned will be excluded. Patients will be randomised 1:1:1 to either standard silicone (comparator), antibiotic-impregnated, or silver-impregnated VPS. The primary outcome measure is time to VPS infection. Secondary outcome measures include time to VPS failure of any cause, reason for VPS failure (infection, mechanical failure, or patient failure), types of bacterial VPS infection (organism type and antibiotic resistance), and incremental cost per VPS failure averted.

Discussion

The British antibiotic and silver-impregnated catheters for ventriculoperitoneal shunts multi-centre randomised controlled trial (the BASICS trial) is the first multi-centre RCT designed to determine whether antibiotic or silver-impregnated VPS reduce early shunt infection compared to standard silicone VPS. The results of this study will be used to inform current neurosurgical practice and may potentially benefit patients undergoing shunt surgery in the future.

Trial registration

International Standard Randomised Controlled Trial Number: ISRCTN49474281.     

Thermal plasticity of skeletal muscle mitochondrial activity and whole animal respiration in a common intertidal triplefin fish,Forsterygion lapillum (Family: Tripterygiidae)

Oxygen demand generally increases in ectotherms as temperature rises in order to sustain oxidative phosphorylation by mitochondria. The thermal plasticity of ectotherm metabolism, such as that of fishes, dictates a species survival and is of importance to understand within an era of warming climates. Within this study the whole animal O₂ consumption rate of a common New Zealand intertidal triplefin fish, Forsterygion lapillum, was investigated at different acclimation temperatures (15, 18, 21, 24 or 25 °C) as a commonly used indicator of metabolic performance. In addition, the mitochondria within permeabilised skeletal muscle fibres of fish acclimated to a moderate temperature (18 °C Cool acclimation group—CA) and a warm temperature (24 °C. Warm acclimation group—WA) were also tested at 18, 24 and 25 °C in different states of coupling and with different substrates. These two levels of analysis were carried out to test whether any peak in whole animal metabolism reflected the respiratory performance of mitochondria from skeletal muscle representing the bulk of metabolic tissue. While standard metabolic rate (SMR- an indicator of total maintenance metabolism) and maximal metabolic rate ( \(\dot{M}\) O_{2 max}) both generally increased with temperature, aerobic metabolic scope (AMS) was maximal at 24 °C, giving the impression that whole animal (metabolic) performance was optimised at a surprisingly high temperature. Mitochondrial oxygen flux also increased with increasing assay temperature but WA fish showed a lowered response to temperature in high flux states, such as those of oxidative phosphorylation and in chemically uncoupled states of respiration. The thermal stability of mitochondria from WA fish was also noticeably greater than CA fish at 25 °C. However, the predicted contribution of respirational flux to ATP synthesis remained the same in both groups and WA fish showed higher anaerobic activity as a result of high muscle lactate loads in both rested and exhausted states. CA fish had a comparably lower level of resting lactate and took 30 % longer to fatigue than WA fish. Despite some apparent acclimation capacity of skeletal muscle mitochondria, the ATP synthesis capacity of this species is constrained at high temperatures, and that a greater fraction of metabolism in skeletal muscle appears to be supported anaerobically at higher temperatures. The AMS peak at 24 °C does not therefore represent utilisation efficiency of oxygen but, rather, the temperature where scope for oxygen flow is greatest.     

Systematics,Taxonomy, and the New Flora of the Bahamian Archipelago

A history of botanical exploration in the Bahama Archipelago is given, and is presented in three sections. The first section begins with the earliest botanical collections in 1700 by Thomas Walker and describes, in chronological order, botanical collections made up to 1920, when Britton and Millspaugh published the first Bahama flora. The second section chronicles botanical research in the archipelago after 1920, up until the publication by Correll and Correll of the Flora of the Bahama Archipelago in 1982. The third section describes plant research in the archipelago between 1982 and the present day. Following a brief rationale for the need for a new flora, the present research toward the flora is discussed, and an example of changes in the flora since 1982 is presented, with changes in the fern flora tabulated.     

Substituted 2H-isoquinolin-1-ones as potent Rho-kinase inhibitors: Part 2, optimization for blood pressure reduction in spontaneously hypertensive rats

Phenylglycine substituted isoquinolones 1 and 2 have previously been described as potent dual ROCK1/ROCK2 inhibitors. Here we describe the further SAR of this series to improve metabolic stability and rat oral exposure. Piperidine analog 20 which demonstrates sustained blood pressure normalization in an SHR blood pressure reduction model was identified through this effort.     

Polymorphisms in the glucocorticoid receptor gene that modulate glucocorticoid sensitivity are associated with rheumatoid arthritis

Introduction  

The glucocorticoid receptor (GR) plays an important regulatory role in the immune system. Four polymorphisms in the GR gene are associated with differences in glucocorticoid (GC) sensitivity; the minor alleles of the polymorphisms N363 S and BclI are associated with relative hypersensitivity to GCs, while those of the polymorphisms ER22/23EK and 9β are associated with relative GC resistance. Because differences in GC sensitivity may influence immune effector functions, we examined whether these polymorphisms are associated with the susceptibility to develop Rheumatoid Arthritis (RA) and RA disease severity.     

Illuminating the molecular basis of diabetic arteriopathy: A proteomic comparison of aortic tissue from diabetic and healthy rats

Arterial disease is a major diabetic complication, yet the component molecular mechanisms of diabetic arteriopathy remain poorly understood. In order to identify major proteins/pathways implicated in diabetic arteriopathy, we studied the effect of 16‐wk untreated streptozotocin‐induced diabetes on the rat aortic proteome. Specific protein levels in isolated aortas were compared in six discrete, pair‐wise (streptozotocin‐diabetic and non‐diabetic age‐matched controls) experiments in which individual proteins were identified and quantified by iTRAQ combined with LC‐MS/MS. A total of 398 unique non‐redundant proteins were identified in at least one experiment and 208 were detected in three or more. Between‐group comparisons revealed significant changes or trends towards changes in relative abundance of 51 proteins (25 increased, 26 decreased). Differences in levels of selected proteins were supported by Western blotting and/or enzyme assays. The most prominent diabetes‐associated changes were in groups of proteins linked to oxidative stress responses and the structure/function of myofibrils and microfilaments. Indexes of mitochondrial content were measurably lower in aortic tissue from diabetic animals. Functional cluster analysis also showed decreased levels of glycolytic enzymes and mitochondrial electron transport system‐complex components. These findings newly implicate several proteins/functional pathways in the pathogenesis of arteriosclerosis/diabetic arteriopathy.     

Serum proteome profiles identifies parathyroid hormone physiologic response

Parathyroid hormone (amino acids 1-34) (PTH) regulates bone and calcium homeostasis. The magnitude of the effects of PTH on bone varies in osteoporosis patients. We employed ProteinChip technology to generate protein profiles from sera of mice treated once daily with PTH or vehicle for 3 or 11 days. Data analyses on selected arrays indicated significant increases in serum proteins or peptides in PTH-treated groups, compared to vehicle-controls. The magnitude of change increased with duration of treatment. Anion-exchange fractionation of sera prior to profiling on array surfaces increased the number of proteins detected that were regulated by PTH. The optimized purification conditions developed "on-chip" for subsets of proteins, reflected corresponding behavior with process-compatible chromatographic resins under elution chromatography. We have identified and evaluated subsets of serum proteins regulated by PTH treatment, using a combination of ProteinChip technology, column chromatography, PAGE and LC-MS/MS. Our data demonstrate the feasibility of using a panel of serum proteins to detect PTH responsiveness in humans.     

Animal regeneration: ancestral character or evolutionary novelty?

An old question about regeneration is whether it is an ancestral character which is a general property of living matter, or whether it represents a set of specific adaptations to the different circumstances faced by different types of animal. In this review, some recent results on regeneration are assessed to see if they can throw any new light on this question. Evidence in favour of an ancestral character comes from the role of Wnt and bone morphogenetic protein signalling in controlling the pattern of whole‐body regeneration in acoels, which are a basal group of bilaterian animals. On the other hand, there is some evidence for adaptive acquisition or maintenance of the regeneration of appendages based on the occurrence of severe non‐lethal predation, the existence of some novel genes in regenerating organisms, and differences at the molecular level between apparently similar forms of regeneration. It is tentatively concluded that whole‐body regeneration is an ancestral character although has been lost from most animal lineages. Appendage regeneration is more likely to represent a derived character resulting from many specific adaptations.