The Why and How of Ultrasmall Nanoparticles

ConspectusIn this Account, we describe our research into ultrasmall nanoparticles, including their unique properties, and outline some of the new opportunities they offer. We will summarize our perspective on the current state of the field and highlight what we see as key questions that remain to be solved. First, there are several nanostructure size-scale regimes, with qualitatively distinct functional biological attributes. Broadly generalized, larger particles (e.g., larger than 300 nm) tend to be more efficiently swept away by the first line of the immune system (for example macrophages). In the "middle-sized" regime (20-300 nm), nanoparticle surfaces and shapes can be recognized by energy-dependent cellular reorganizations, then organized locally in a spatial and temporally coherent way. That energy is gated and made available by specific cellular recognition processes. The relationship between particle surface design, endogenously derived nonspecific biomolecular corona, and architectural features recognized by the cell is complex and only purposefully and very precisely designed nanoparticle architectures are able to navigate to specific targets. At sufficiently small sizes (<10 nm including the ligand shell, associated with a core diameter of a few nm at most) we enter the "quasi-molecular regime" in which the endogenous biomolecular environment exchanges so rapidly with the ultrasmall particle surface that larger scale cellular and immune recognition events are often greatly simplified. As an example, ultrasmall particles can penetrate cellular and biological barriers within tissue architectures via passive diffusion, in much the same way as small molecule drugs do. An intriguing question arises: what happens at the interface of cellular recognition and ultrasmall quasi-molecular size regimes? Succinctly put, ultrasmall conjugates can evade defense mechanisms driven by larger scale cellular nanoscale recognition, enabling them to flexibly exploit molecular interaction motifs to interact with specific targets. Numerous advances in control of architecture that take advantage of these phenomena have taken place or are underway. For instance, syntheses can now be sufficiently controlled that it is possible to make nanoparticles of a few hundreds of atoms or metalloid clusters of several tens of atoms that can be characterized by single crystal X-ray structure analysis. While the synthesis of atomically precise clusters in organic solvents presents challenges, water-based syntheses of ultrasmall nanoparticles can be upscaled and lead to well-defined particle populations. The surface of ultrasmall nanoparticles can be covalently modified with a wide variety of ligands to control the interactions of these particles with biosystems, as well as drugs and fluorophores. And, in contrast to larger particles, many advanced molecular analytical and separation tools can be applied to understand their structure. For example, NMR spectroscopy allows us to obtain a detailed image of the particle surface and the attached ligands. These are considerable advantages that allow further elaboration of the level of architectural control and characterization of the ultrasmall structures required to access novel functional regimes and outcomes. The ultrasmall nanoparticle regime has a unique status and provides a potentially very interesting direction for development.

How safe are gloves and masks used for protection against Legionella longbeachae infection when gardening?

Legionella longbeachae has been frequently identified in composted plant material and can cause Legionnaires' disease (LD). We wanted to determine how frequently L. longbeachae DNA was present on gardeners' gloves, and how long L. longbeachae could persist on inoculated gloves and masks. Volunteers completed a survey of gardening practices and their gardening gloves were tested for L. longbeachae DNA by qPCR. The persistence of viable L. longbeachae was assessed by timed subcultures after inoculation of gardening gloves and masks. Gloves but not masks were used regularly. L. longbeachae was detected on 11 (14%; 95% CI 8-24%) gloves. Viable organisms were recovered from 25-50% of inoculated cotton, leather and PU coated gloves but not rubber gloves after 8 h incubation. There was a difference in dose-response curve slopes by glove material (P = 0·001) and time to 50% sterility (P = 0·036). There were differences in persistence of L. longbeachae between mask types from analysis of the slopes and 50% sterility on the decay curves (P = 0·042, P < 0·001 respectively). Gardening gloves and masks may act as a vector for transmission of L. longbeachae during gardening. Washing gardening gloves and prompt disposal of masks could reduce risk of LD.

Adaptation of the Problem Management Plus programme for Syrian, Eritrean and Afghan refugee youth

Background

Common mental health problems are prevalent among refugee minors and impair their daily functioning. Due to various barriers such as lack of culturally appropriate treatments, waiting lists, and stigma they have limited access to care. Problem Management Plus (PM+) was developed by the World Health Organization to address these barriers. PM+ is transdiagnostic, delivered by non-professional helpers, and consists of 5 sessions of problem-solving skills, behavioural activation and stress management. PM+ is effective in reducing adults' distress and improve functioning. We aimed to adapt PM+ for refugee minors and add an emotional processing module to target symptoms of posttraumatic stress disorder.

Methods

We culturally and contextually adapted PM+ for use in Syrian, Eritrean and Afghan refugee minors (age 16-18 years). Data were collected through: 1) free list interviews with Syrian, Eritrean and Afghan refugee minors (n = 30), 2) key informant interviews with knowledgeable refugees (n = 6), professionals (n = 6), policy makers (n = 6) and 3) focus group discussions (n = 24). Data were analysed in ATLAS.ti through inductive and deductive framework analysis.

Results

The interviews with youth revealed daily life problems around the following themes: language, family and peers, and substance use. The overall results suggested the need for culture- and age-specific adaptations of 1) the PM+ manual content (language, metaphors, illustrations) and 2) intervention delivery (modality, content and presentation of the trauma processing module, and duration).

Conclusions

This study led to specific adaptations of PM+ for refugee adolescents to be used in two randomized controlled trials in the Netherlands and Sweden.

Key message

Refugee minors face numerous barriers reaching mental health care. Scalable, culturally adapted psychological interventions should be developed and evaluated to address common mental disorders in refugee youth.

Localising evidence for decision-making: participatory approach to inform schistosomiasis control

Background

The linear theories of change which ground many interventions do not account for the complex processes and systems in which they are implemented. This reductionist approach prioritises statistical methods which do not accommodate the stochastic, non-linear, dynamic interactions between humans and their environment. The inclusion of practitioners in the process of evidence development and utilisation of complex systems methods mitigates these issues and results in locally relevant, timely evidence for decision-making.

Methods

The aim of this work was to develop localised evidence for decision-making for schistosomiasis control in Uganda, Malawi, and Tanzania. Workshops were conducted with practitioners from the Ministries of Health at various levels and partner organisations to identify evidence needs for their decision-making processes and perceptions of disease transmission and control activities. Participatory systems mapping was used to identify factors directly and indirectly related to transmission. The maps were synthesised to a master complex systems map, which served as the blueprint for a generalised spatial agent-based model and specific ABMs tailored to the evidence needs of decision-makers.

Results

There was a gap in available evidence for practitioners to advocate for resources within the MoH and government budgets, as well as intervention efficacy and resource allocation. The adaptable and data-inclusive characteristics of the AMBs made them well-suited to produce localised outputs. Converted to NetLogo with a tailored user interface, these models were appropriate and responsive to the needs of decision-makers from village to national levels and across country contexts.

Conclusions

Used together, participatory and agent-based modelling resulted in the development of responsive and relevant evidence for practitioner decision-making. This process is generalisable and transferable to other diseases and locations outside of those in this study.

Key messages

The use of participatory systems mapping to develop agent-based models resulted in relevant and timely evidence for practitioner decision-making. The approach used here is transferable and generalisable outside schistosomiasis control and the contexts in this study.

Malignant rhabdoid tumor arising in a mixed epithelial, stromal tumor of kidney: report of a male case, review of the literature

Mixed epithelial and stromal tumor (MEST) of the kidney is a rare biphasic tumor composed of both stromal and epithelial components, the latter showing a variable proportion of solid to cystic areas. These tumors show a marked female predominance, commonly occur in perimenopausal age groups, and often have an ovarian-type stroma with ER and PR positivity, suggesting steroids may play a role in pathogenesis. Although typically benign, rare cases showing malignant transformation have been reported. We present a case of a 42-year-old man with a 10 cm right kidney mass located in the renal pelvis. Histologically, the majority of the tumor was composed of a diffuse, sheet-like growth of malignant cells demonstrating a rhabdoid morphology with large nuclei, prominent nucleoli, and eosinophilic eccentric cytoplasm. Brisk mitotic activity and coagulative type necrosis was also noted. Intimately associated with this malignant rhabdoid component was a much smaller portion of tumor featuring variably sized bland epithelial tubules embedded within a stroma composed of bland spindle cells and areas of hyalinization, diagnostic of MEST. By immunohistochemistry, the malignant rhabdoid tumor portion of the neoplasm showed complete loss of nuclear INI-1, while the MEST component retained nuclear expression of this antigen. With these features taken together, our case represents a malignant rhabdoid tumor arising in a background of MEST. To our knowledge, this case represents the first case of a MEST showing malignant transformation in the form of malignant rhabdoid tumor in a male patient in the English language literature.

Evaluating feasibility and acceptability of a group WHO trans-diagnostic intervention for women with common mental disorders in rural Pakistan: a cluster randomised controlled feasibility trial

AIMS

The aim of this feasibility trial was to evaluate the feasibility and acceptability of the locally adapted Group Problem Management Plus (PM+) intervention for women in the conflict affected settings in Swat, Pakistan.

METHODS

This mixed-methods study incorporated a quantitative component consisting of a two arm cluster randomised controlled feasibility trial, and qualitative evaluation of the acceptability of the Group PM+ to a range of stakeholder groups. For the quantitative component, on average from each of the 20 Lady Health Workers (LHWs) catchment area (20 clusters), six women were screened and recruited for the trial with score of >2 on the General Health Questionnaire and score of >16 on the WHO Disability Assessment Schedule. These LHW clusters were randomised on a 1 : 1 allocation ratio using a computer-based software through a simple randomisation method to the Group PM+ intervention or Enhanced Usual Care. The Group PM+ intervention consisted of five weekly sessions of 2 h duration delivered by local non-specialist females under supervision. The primary outcome was individual psychological distress, measured by levels of anxiety and depression on the Hospital Anxiety and Depression Scale at 7th week after baseline. Secondary outcomes include symptoms of depression, post-traumatic stress disorder (PTSD), general psychological profile, levels of functioning and generalised psychological distress. Intervention acceptability was explored through in-depth interviews.

RESULTS

The results show that lay-helpers with no prior mental health experience can be trained to achieve the desired competency to successfully deliver the intervention in community settings under supervision. There was a good intervention uptake, with Group PM+ considered useful by participants, their families and lay-helpers. The outcome evaluation, which was not based on a large enough study to identify statistically significant results, indicated statistically significant improvements in depression, anxiety, general psychological profile and functioning. The PTSD symptoms and depressive disorder scores showed a trend in favour of the intervention.

CONCLUSION

This trial showed robust acceptance in the local settings with delivery by non-specialists under supervision by local trained females. The trial paves the way for further adaptation and exploration of the outcomes through larger-scale implementation and definitive randomised controlled trials in the local settings.

Impact of cationic polystyrene nanoparticles (PS-NH2) on early embryo development of Mytilus galloprovincialis: Effects on shell formation

The potential release of nanoparticles (NPs) into aquatic environments represents a growing concern for their possible impact on aquatic organisms. In this light, exposure studies during early life stages, which can be highly sensitive to environmental perturbations, would greatly help identifying potential adverse effects of NPs. Although in the marine bivalve Mytilus spp. the effects of different types of NPs have been widely investigated, little is known on the effects of NPs on the developing embryo. In M. galloprovincialis, emerging contaminants were shown to affect gene expression profiles during early embryo development (from trocophorae-24 hpf to D-veligers-48 hpf). In this work, the effects of amino-modified polystyrene NPs (PS-NH₂) on mussel embryos were investigated. PS-NH₂ affected the development of normal D-shaped larvae at 48 hpf (EC₅₀ = 0.142 mg/L). Higher concentrations (5-20 mg/L) resulted in high embryotoxicity/developmental arrest. At concentrations ≅ EC₅₀, PS-NH₂ affected shell formation, as shown by optical and polarized light microscopy. In these conditions, transcription of 12 genes involved in different biological processes were evaluated. PS-NH₂ induced dysregulation of transcription of genes involved in early shell formation (Chitin synthase, Carbonic anhydrase, Extrapallial Protein) at both 24 and 48 hpf. Decreased mRNA levels for ABC transporter p-glycoprotein-ABCB and Lysozyme were also observed at 48 hpf. SEM observations confirmed developmental toxicity at higher concentrations (5 mg/L). These data underline the sensitivity of Mytilus early embryos to PS-NH₂ and support the hypothesis that calcifying larvae of marine species are particularly vulnerable to abiotic stressors, including exposure to selected types of NPs.

Interactions of cationic polystyrene nanoparticles with marine bivalve hemocytes in a physiological environment: Role of soluble hemolymph proteins

The bivalve Mytilus galloprovincialis has proven as a suitable model invertebrate for evaluating the potential impact of nanoparticles (NPs) in the marine environment. In particular, in mussels, the immune system represents a sensitive target for different types of NPs. In environmental conditions, both NP intrinsic properties and those of the receiving medium will affect particle behavior and consequent bioavailability/uptake/toxicity. However, the evaluation of the biological effects of NPs requires additional understanding of how, once within the organism, NPs interact at the molecular level with cells in a physiological environment. In mammalian systems, different NPs associate with serum soluble components, organized into a "protein corona", which affects particle interactions with target cells. However, no information is available so far on the interactions of NPs with biological fluids of aquatic organisms. In this work, the influence of hemolymph serum (HS) on the in vitro effects of amino modified polystyrene NPs (PS-NH2) on Mytilus hemocytes was investigated. Hemocytes were incubated with PS-NH2 suspensions in HS (1, 5 and 50µg/mL) and the results were compared with those obtained in ASW medium. Cell functional parameters (lysosomal membrane stability, oxyradical production, phagocytosis) were evaluated, and morphological changes were investigated by TEM. The activation state of the signalling components involved in Mytilus immune response (p38 MAPK and PKC) was determined. The results show that in the presence of HS, PS-NH2 increased cellular damage and ROS production with respect to ASW medium. The effects were apparently mediated by disregulation of p38 MAPK signalling. The formation of a PS-NH2-protein corona in HS was investigated by centrifugation, and 1D- gel electrophoresis and nano-HPLC-ESI-MS/MS. The results identified the Putative C1q domain containing protein (MgC1q6) as the only component of the PS-NH2 hard protein corona in Mytilus hemolymph. These data represent the first evidence for the formation of a NP bio-corona in aquatic organisms and underline the importance of the recognizable biological identity of NPs in physiological exposure medium when testing their potential impact environmental model organisms. Although the results obtained in vitro do not entirely reflect a realistic exposure scenario and the more complex formation of a bio-corona that is likely to occur in vivo, these data will contribute to a better understanding of the effects of NPs in marine invertebrates.

Neutral red retention time assay in determination of toxicity of nanoparticles

The neutral red retention time (NRRT) assay is useful for detecting decreased lysosomal membrane stability in haemocytes sampled from bivalves, a phenomenon often associated with exposure to environmental pollutants including nanomaterials. Bivalves are popular sentinel species in ecotoxicology and use of NRRT in study of species in the genus Mytilus is widespread in environmental monitoring. The NRRT assay has been used as an in vivo test for toxicity of carbon nanoparticles (Moore MN, Readman JAJ, Readman JW, Lowe DM, Frickers PE, Beesley A. 2009. Lysosomal cytotoxicity of carbon nanoparticles in cells of the molluscan immune system: An in vivo study. Nanotoxicology. 3 (1), 40-45). We here report application of this assay adapted to a microtitre plate format to a panel of metal and metal oxide nanoparticles (2 ppm). This showed that copper, chromium and cobalt nanoparticles are toxic by this criterion while gold and titanium nanoparticles are not. As the former three nanoparticles are often reported to be cytotoxic while the latter two are thought to be non-cytotoxic, these data support use of NRRT as a general in vitro assay in nanotoxicology.

In Vivo Biomolecule Corona around Blood-Circulating, Clinically Used and Antibody-Targeted Lipid Bilayer Nanoscale Vesicles

The adsorption of proteins and their layering onto nanoparticle surfaces has been called the "protein corona". This dynamic process of protein adsorption has been extensively studied following in vitro incubation of many different nanoparticles with plasma proteins. However, the formation of protein corona under dynamic, in vivo conditions remains largely unexplored. Extrapolation of in vitro formed protein coronas to predict the fate and possible toxicological burden from nanoparticles in vivo is of great interest. However, complete lack of such direct comparisons for clinically used nanoparticles makes the study of in vitro and in vivo formed protein coronas of great importance. Our aim was to study the in vivo protein corona formed onto intravenously injected, clinically used liposomes, based on the composition of the PEGylated liposomal formulation that constitutes the anticancer agent Doxil. The formation of in vivo protein corona was determined after the recovery of the liposomes from the blood circulation of CD-1 mice 10 min postinjection. In comparison, in vitro protein corona was formed by the incubation of liposomes in CD-1 mouse plasma. In vivo and in vitro formed protein coronas were compared in terms of morphology, composition and cellular internalization. The protein coronas on bare (non-PEGylated) and monoclonal antibody (IgG) targeted liposomes of the same lipid composition were also comparatively investigated. A network of linear fibrillary structures constituted the in vitro formed protein corona, whereas the in vivo corona had a different morphology but did not appear to coat the liposome surface entirely. Even though the total amount of protein attached on circulating liposomes correlated with that observed from in vitro incubations, the variety of molecular species in the in vivo corona were considerably wider. Both in vitro and in vivo formed protein coronas were found to significantly reduce receptor binding and cellular internalization of antibody-conjugated liposomes; however, the in vivo corona formation did not lead to complete ablation of their targeting capability.

Effect of an immunomodulatory feed additive on markers of immunity in pasture-fed dairy cows

BACKGROUND

Infectious diseases in dairy cows often follow a time of nutritional or physiological stress and the subsequent altered immune system function. This study aimed to determine if the immunomodulatory effects of a feed additive previously observed in experimental animals and housed cattle fed total mixed rations could be reproduced in pasture-fed dairy cattle under Australian conditions.

METHODS

The study included 34 pasture-fed dairy cattle given the treatment (n = 17) or placebo (bentonite, n = 17) for an acclimation period of 15 days followed by 60 days of supplementation. Blood tests were taken pre-trial and then 30, 60 and 90 days after acclimation. Blood samples were extracted and preserved in Trizol and analysed for immune markers.

RESULTS

Pasture-fed dairy cows in the treatment group had significantly higher levels of the immune markers interleukin-8R and L-selectin in comparison with placebo-fed cows at 60 days after the start of supplementation.

CONCLUSION

The immunomodulatory effects of the additive observed in the current study and the associated enhanced neutrophil function demonstrated by other studies suggest a role in decreasing the rates of mastitis and other infectious diseases of dairy cattle, particularly during times of nutritional or physiological stress.

Abstract B56: Transfer of senescent signals in a hypoxic tumor microenvironment: A mechanism of tumor cell survival mediated by exosomes

Triple Negative Breast Cancers (TNBCs) are a histological subtype of breast tumors which are innately hypoxic; a tumor microenvironment integral to chemoresistance and aggressive tumor behaviour. Importantly, hypoxia can drive viable cellular fate mechanisms rendering cancer cells capable of by-passing apoptotic cell death when chemotherapeutically challenged. Moreover, exosomes (nanovesicles 40-150nm of endocytic origin) preferentially released in the hypoxic environment can potentially be trafficked into neighbouring cells thereby mediating communication and propagating chemoresistance. The objective of this study was to establish if exosomes released from the TNBC cell line MDA-MB-231 (MSL) grown in a hypoxic environment, can mediate the transfer of viable cellular fate signatures (senescent and autophagic) to non-hypoxic cells rendering them non-apoptotic and chemoresistant.

Experimentally, MDA-MB-231 (MSL) TNBC cells were cultured in hypoxia (1%) for 0-96 hours. Senescent, autophagic and cell cycle markers (LC3, p21, HDAC6, TSG101 and MAD2) were analysed by Western Blot. Nanoparticle Tracking Analysis (NTA), performed on the Nanosight LM10 microscope, allowed the enumeration and characterisation of harvested exosomes, while Dil labelled fluorescent imaging confirmed exosomal uptake in vitro.

Hypoxic exposure (1%) of the MDA-MB-231 (MSL) confirmed by an increase in HIF1a, demonstrated that cellular senescence (p21), autophagy (LC3II), HDAC6 and the tumor susceptibility gene 101 (TSG101) markers increased in prolonged hypoxic exposure. Prolonged hypoxic exposure was also shown to result in an increase in the number of exosomes released from MDA-MB-231 (MSL) cells. siRNA knockdown of TSG101, a component of the ESCRT pathway involved in exosome release, resulted in a decrease in the amount of exosomes released from MDA-MB-231 (MSL) cells.

In summary, it is well established in the literature that TNBCs are more hypoxic and chemoresistant than non-TNBC histological subtypes. The fact that both senescence and autophagy are induced in this environment underlies the ability of cancer cells to maintain viability. Moreover, exosomal release is enhanced in hypoxia thereby facilitating signalling between cancer cells with the potential to propagate chemoresistance. We suggest that targeting TSG101 thereby impeding exosomal release has the potential to cessate communication between cells in hypoxia thereby promoting apoptotic cell death in cells that are chemotherapeutically challenged.

Funding: The Mater Surgical Oncology Research Appeal, and Mater Breast Health Research

Citation Format: Luke Gubbins, Karolina Weiner-Gorzel, Shiva Sharma, Laura Cooke, Anna Salvati, Jeremy Simpson, Kenneth Dawson, Malcolm Kell, Amanda McCann. Transfer of senescent signals in a hypoxic tumor microenvironment: A mechanism of tumor cell survival mediated by exosomes. [abstract]. In: Abstracts: AACR Special Conference on Cellular Heterogeneity in the Tumor Microenvironment; 2014 Feb 26-Mar 1; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(1 Suppl):Abstract nr B56. doi:10.1158/1538-7445.CHTME14-B56

Unusual presentation of Sjögren's syndrome

We present a case of a 67-year-old woman admitted from the neurology clinic for further investigations of progressive ataxia and sensory symptoms. Neurological examination showed reduced pinprick and absent vibration sensations in the lower limbs. Motor system examination was normal. Her antinuclear antibodies titre was 1:100 with positive Ro antibodies. Her initial nerve conduction studies were normal. However, the lower limb somatosensory-evoked potentials (SSEP) demonstrated impairment of central sensory conduction pathway. Rheumatology review revealed a history of fatigue and Sicca symptoms and her Schirmer's test was strongly positive. This lead to the diagnosis of ganglionopathy associated to Sjögren's syndrome. She had an excellent response to intravenous methylprednisolone followed by oral prednisolone and intravenous cyclophosphamide infusions. This case highlights that dorsal column involvement can precede the diagnosis of primary Sjögren's syndrome.

Examination of the follicular lymphoma international prognostic index (FLIPI) in the National LymphoCare study (NLCS): a prospective US patient cohort treated predominantly in community practices

BACKGROUND

Because follicular lymphoma (FL) patients have heterogeneous outcomes, the FL international prognostic index (FLIPI) was developed to risk-stratify patients and to predict survival. However, limited data exist regarding the role of FLIPI in the era of routine first-line rituximab (R) and R-chemotherapy regimens and in the setting of community oncology practices.

PATIENTS AND METHODS

We evaluated the outcome data from the National LymphoCare Study (NLCS), a prospective, observational cohort study, which collects data on patients with FL in the United States (US) community practices.

RESULTS

Among 1068 male and 1124 female patients with FLIPI data, most were treated in US community practices (79%); 35% were FLIPI good risk, 30% intermediate risk, and 35% poor risk. FLIPI risk groups were significant predictors of overall survival (OS) and progression-free survival (PFS) for patients who undergo watchful waiting (WW), and those who receive non-R-containing regimens, R-alone, and R-chemotherapy combinations.

CONCLUSIONS

In the setting of contemporary practice with routine R use, stratifying patients into good, intermediate, and poor FLIPI risk groups predicts distinct outcomes in terms of OS and PFS. FLIPI remains an important prognostic index in the R era and should be used in clinical practices to support discussions about prognosis.

Animal-level factors affecting ovarian function in Bos indicus heifers treated to synchronize ovulation with intravaginal progesterone-releasing devices and oestradiol benzoate

The primary objective of this study was to investigate the impact of animal-level factors including energy balance and environmental/management stress, on the ovarian function of Bos indicus heifers treated to synchronize ovulation. Two-year-old Brahman (BN) (n = 30) and BN-cross (n = 34) heifers were randomly allocated to three intravaginal progesterone-releasing device (IPRD) treatment groups: (i) standard-dose IPRD [Cue-Mate(®) (CM) 1.56 g; n = 17]; (ii) half-dose IPRD [0.78 g progesterone (P(4)); CM 0.78 g; n = 15]; (iii) half-dose IPRD + 300 IU equine chorionic gonadotrophin at IPRD removal (CM 0.78 g + G; n = 14); (iv) and a control group, 2× PGF(2α) [500 μg prostaglandin F(2α) (PGF(2α))] on Day -16 and -2 (n = 18). Intravaginal progesterone-releasing device-treated heifers received 250 μg PGF(2α) at IPRD insertion (Day -10) and IPRD removal (Day -2) and 1 mg oestradiol benzoate on Day -10 and -1. Heifers were managed in a small feedlot and fed a defined ration. Ovarian function was evaluated by ultrasonography and plasma P(4) throughout the synchronized and return cycles. Energy balance was evaluated using plasma insulin-like growth factor 1 (IGF-I) and glucose concentrations. The impact of environmental stressors was evaluated using plasma cortisol concentration. Heifers that had normal ovarian function had significantly higher IGF-I concentrations at commencement of the experiment (p = 0.008) and significantly higher plasma glucose concentrations at Day -2 (p = 0.040) and Day 4 (p = 0.043), than heifers with abnormal ovarian function. There was no difference between the mean pre-ovulatory cortisol concentrations of heifers that ovulated or did not ovulate. However, heifers that ovulated had higher cortisol concentrations at Day 4 (p = 0.056) and 6 (p = 0.026) after ovulation than heifers that did not ovulate.

The evolution of the protein corona around nanoparticles: a test study

The importance of the protein corona formed around nanoparticles upon entering a biological fluid has recently been highlighted. This corona is, when sufficiently long-lived, thought to govern the particles' biological fate. However, even this long-lived "hard" corona evolves and re-equilibrates as particles pass from one biological fluid to another, and may be an important feature for long-term fate. Here we show the evolution of the protein corona as a result of transfer of nanoparticles from one biological fluid (plasma) into another (cytosolic fluid), a simple illustrative model for the uptake of nanoparticles into cells. While no direct comparison can be made to what would happen in, for example, the uptake pathway, the results confirm that significant evolution of the corona occurs in the second biological solution, but that the final corona contains a "fingerprint" of its history. This could be evolved to map the transport pathways utilized by nanoparticles, and eventually to predict nanoparticle fate and behavior.

Activation of stress-related signalling pathway in human cells upon SiO2 nanoparticles exposure as an early indicator of cytotoxicity

BACKGROUND

Nanomaterials such as SiO2 nanoparticles (SiO2NP) are finding increasing applications in the biomedical and biotechnological fields such as disease diagnostics, imaging, drug delivery, food, cosmetics and biosensors development. Thus, a mechanistic and systematic evaluation of the potential biological and toxic effects of SiO2NP becomes crucial in order to assess their complete safe applicability limits.

RESULTS

In this study, human monocytic leukemia cell line THP-1 and human alveolar epithelial cell line A549 were exposed to a range of amorphous SiO2NP of various sizes and concentrations (0.01, 0.1 and 0.5 mg/ml). Key biological indicators of cellular functions including cell population density, cellular morphology, membrane permeability, lysosomal mass/pH and activation of transcription factor-2 (ATF-2) were evaluated utilizing quantitative high content screening (HCS) approach and biochemical techniques. Despite the use of extremely high nanoparticle concentrations, our findings showed a low degree of cytotoxicity within the panel of SiO2NP investigated. However, at these concentrations, we observed the onset of stress-related cellular response induced by SiO2NP. Interestingly, cells exposed to alumina-coated SiO2NP showed low level, and in some cases complete absence, of stress response and this was consistent up to the highest dose of 0.5 mg/ml.

CONCLUSIONS

The present study demonstrates and highlights the importance of subtle biological changes downstream of primary membrane and endocytosis-associated phenomena resulting from high dose SiO2NP exposure. Increased activation of transcription factors, such as ATF-2, was quantitatively assessed as a function of i) human cell line specific stress-response, ii) SiO2NP size and iii) concentration. Despite the low level of cytotoxicity detected for the amorphous SiO2NP investigated, these findings prompt an in-depth focus for future SiO2NP-cell/tissue investigations based on the combined analysis of more subtle signalling pathways associated with accumulation mechanisms, which is essential for establishing the bio-safety of existing and new nanomaterials.

Exposure assessment: recommendations for nanotechnology-based pesticides

Given the development of nanotechnology within numerous scientific disciplines, it is likely that nanoscale products have been and will be used for agricultural, vector, and urban pest control prior to a complete evaluation of exposure and risk. Significant differences may exist between nanotechnology-based pesticides (NBPs) and conventional pesticides, primarily due to size and surface characteristics. These differences may result in changes in bioavailability, sensitivity, dosimetry, and pharmacokinetics. This paper considers the role of exposure assessment in the regulation of NBPs. While the existing regulatory infrastructure for pesticides is well established, several issues specific to NBP exposure are discussed, including: (1) disclosures of nanoparticle characteristics in product formulations; (2) additional uncertainty factors for NBPs with inadequate data; (3) route-specific approaches for assessing exposure; (4) testing with the commercial form of NBPs; (5) initiation of a health surveillance program; and (6) development of educational programs.

A randomised controlled trial of cognitive behaviour therapy for psychosis in a routine clinical service

OBJECTIVE

To evaluate cognitive behaviour therapy for psychosis (CBTp) delivered by non-expert therapists, using CBT relevant measures.

METHOD

Participants (N = 74) were randomised into immediate therapy or waiting list control groups. The therapy group was offered 6 months of therapy and followed up 3 months later. The waiting list group received therapy after waiting 9 months (becoming the delayed therapy group).

RESULTS

Depression improved in the combined therapy group at both the end of therapy and follow-up. Other significant effects were found in only one of the two therapy groups (positive symptoms; cognitive flexibility; uncontrollability of thoughts) or one of the two time points (end of therapy: general symptoms, anxiety, suicidal ideation, social functioning, resistance to voices; follow-up: power beliefs about voices, negative symptoms). There was no difference in costs between the groups.

CONCLUSION

The only robust improvement was in depression. Nevertheless, there were further encouraging but modest improvements in both emotional and cognitive variables, in addition to psychotic symptoms.

Intramuscular interferon beta-1a in chronic inflammatory demyelinating polyradiculoneuropathy

OBJECTIVE

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) shares immunologic features with multiple sclerosis (MS). Because IM interferon beta-1a (IM IFNbeta-1a) is an effective and safe treatment for MS, we conducted a dose-ranging efficacy study of IFNbeta-1a in patients with CIDP.

METHODS

Adults with IV immunoglobulin (IVIg)-dependent CIDP (n = 67) were enrolled in this 32-week double-blind trial and randomized to IM IFNbeta-1a. Patients received 30 microg once weekly plus placebo (n = 12), IM IFNbeta-1a 60 microg once weekly plus placebo (n = 11), IM IFNbeta-1a 30 microg twice weekly (n = 11), IM IFNbeta-1a 60 microg twice weekly (n = 11), or placebo twice weekly (n = 22). Participants were maintained on IVIg through week 16, when IVIg was discontinued. Patients who worsened were restarted on IVIg. The primary outcome was total IVIg dose (g/kg) administered from week 16 to 32.

RESULTS

There was no difference in total IVIg dose administered after week 16 for patients treated with IFNbeta-1a (1.20 g/kg) compared with placebo (1.34 g/kg; p = 0.75). However, exploratory analyses suggested IFNbeta-1a significantly reduced total dose of IVIg compared with placebo for participants who required either high-dose IVIg (>0.95 g/kg per month) or had greater weakness at baseline (Medical Research Council sum score <51). Adverse events included flu-like symptoms, headache, and fatigue in the IFNbeta-1a groups.

CONCLUSIONS

Interferon beta-1a (IFNbeta-1a) therapy did not provide significant benefit over IV immunoglobulin (IVIg) therapy alone for patients with chronic inflammatory demyelinating polyradiculoneuropathy. However, IFNbeta-1a might be beneficial for patients with more severe disability or those needing high doses of IVIg.

LEVEL OF EVIDENCE

This study was designed to provide Class I evidence for the safety and efficacy of IM IFNbeta-1a in the treatment of CIDP but has been subsequently classified as Class II due to a >20% patient dropout rate. Thus, this randomized, controlled clinical trial provides Class II evidence of no effect on primary and secondary endpoints of 4 dosage regimens of IM IFNbeta-1a added to IVIg in persons with CIDP.

Determinants of survival in behavioral variant frontotemporal dementia

BACKGROUND

Behavioral variant frontotemporal dementia (bvFTD) is a common cause of younger onset dementia. Little is known about its rate of progression but a recently identified subgroup seems to have an excellent prognosis. Other determinants of survival are unclear.

METHODS

We analyzed survival in a large group of clinically diagnosed bvFTD patients (n = 91) with particular attention to demographic and clinical features at presentation. Of the 91 cases, 50 have died, with pathologic confirmation in 28.

RESULTS

Median survival in the whole group was 9.0 years from symptom onset, and 5.4 years from diagnosis. After the exclusion of 24 "phenocopy" cases, the analysis was repeated in a subgroup of 67 patients. The mean age at symptom onset of the pathologic group was 58.5 years and 16% had a positive family history. Their median survival was 7.6 years (95% confidence interval [CI] 6.6-8.6) from symptom onset and 4.2 years (95% CI 3.4-5.0) from diagnosis. The only factor associated with shorter survival was the presence of language impairment at diagnosis.

CONCLUSIONS

Patients with definite frontotemporal dementia have a poor prognosis which is worse if language deficits are also present. This contrasts with the extremely good outcome in those with the phenocopy syndrome: of our 24 patients only 1 has died (of coincident pathology) despite, in some cases, many years of follow-up.