Quantifying engineered nanomaterial toxicity: comparison of common cytotoxicity and gene expression measurements

BACKGROUND: When evaluating the toxicity of engineered nanomaterials (ENMS) it is important to use multiple bioassays based on different mechanisms of action. In this regard we evaluated the use of gene expression and common cytotoxicity measurements using as test materials, two selected nanoparticles with known differences in toxicity, 5 nm mercaptoundecanoic acid (MUA)-capped InP and CdSe quantum dots (QDs). We tested the effects of these QDs at concentrations ranging from 0.5 to 160 µg/mL on cultured normal human bronchial epithelial (NHBE) cells using four common cytotoxicity assays: the dichlorofluorescein assay for reactive oxygen species (ROS), the lactate dehydrogenase assay for membrane viability (LDH), the mitochondrial dehydrogenase assay for mitochondrial function, and the Comet assay for DNA strand breaks. RESULTS: The cytotoxicity assays showed similar trends when exposed to nanoparticles for 24 h at 80 µg/mL with a threefold increase in ROS with exposure to CdSe QDs compared to an insignificant change in ROS levels after exposure to InP QDs, a twofold increase in the LDH necrosis assay in NHBE cells with exposure to CdSe QDs compared to a 50% decrease for InP QDs, a 60% decrease in the mitochondrial function assay upon exposure to CdSe QDs compared to a minimal increase in the case of InP and significant DNA strand breaks after exposure to CdSe QDs compared to no significant DNA strand breaks with InP. High-throughput quantitative real-time polymerase chain reaction (qRT-PCR) data for cells exposed for 6 h at a concentration of 80 µg/mL were consistent with the cytotoxicity assays showing major differences in DNA damage, DNA repair and mitochondrial function gene regulatory responses to the CdSe and InP QDs. The BRCA2, CYP1A1, CYP1B1, CDK1, SFN and VEGFA genes were observed to be upregulated specifically from increased CdSe exposure and suggests their possible utility as biomarkers for toxicity. CONCLUSIONS: This study can serve as a model for comparing traditional cytotoxicity assays and gene expression measurements and to determine candidate biomarkers for assessing the biocompatibility of ENMs.1R01GM84702-01 - National Institute of General Medical Science

Orthogonal and complementary measurements of properties of drug products containing nanomaterials

Quality control of pharmaceutical and biopharmaceutical products, and verification of their safety and efficacy, depends on reliable measurements of critical quality attributes (CQAs). The task becomes particularly challenging for drug products and vaccines containing nanomaterials, where multiple complex CQAs must be identified and monitored. To reduce (i) the risk of measurement bias and (ii) the uncertainty in decision-making during product development, the combination of orthogonal and complementary analytical techniques are generally recommended by regulators. However, despite frequent reference to “orthogonal” and “complementary” in guidance documents, neither term is clearly defined. How does one determine if two analytical methods are orthogonal or complementary to one another? Definitions are needed to design a robust characterization strategy aligned to regulatory needs. Definitions for “orthogonal” and “complementary” are proposed that are compatible with existing metrological terminology and are applicable to complex measurement problems. Orthogonal methods target the quantitative evaluation of the true value of a product attribute to address unknown bias or interference. Complementary measurements include a broader scope of methods that reinforce each other to support a common decision. Examples of the application of these terms are presented, with a focus on measurement of physical properties of nano-enabled drug products, including liposomes and polymeric nanoparticles for cancer treatment, lipid-based nanoparticles (LNPs) and virus-like particles for nucleic acid delivery. The proposed framework represents a first step in advancing the assessment of the orthogonality and complementarity of two measurements and it can potentially serve as the basis for a future international standard. This framework may help product developers to implement more efficient product characterization strategies, accelerate the introduction of novel medicines to the clinic and be applicable to other therapeutics beyond nanomaterial-containing pharmaceuticals.publishedVersio

Treatments for hyperemesis gravidarum and nausea and vomiting in pregnancy: a systematic review and economic assessment

Background: Nausea and vomiting in pregnancy (NVP) affects up to 85% of all women during pregnancy, but for the majority self-management suffices. For the remainder, symptoms are more severe and the most severe form of NVP - hyperemesis gravidarum (HG) - affects 0.3-1.0% of pregnant women. There is no widely accepted point at which NVP becomes HG.Objectives: This study aimed to determine the relative clinical effectiveness and cost-effectiveness of treatments for NVP and HG.Data sources: MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, PsycINFO, Commonwealth Agricultural Bureaux (CAB) Abstracts, Latin American and Caribbean Health Sciences Literature, Allied and Complementary Medicine Database, British Nursing Index, Science Citation Index, Social Sciences Citation Index, Scopus, Conference Proceedings Index, NHS Economic Evaluation Database, Health Economic Evaluations Database, China National Knowledge Infrastructure, Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effects were searched from inception to September 2014. References from studies and literature reviews identified were also examined. Obstetric Medicine was hand-searched, as were websites of relevant organisations. Costs came from NHS sources.Review methods: A systematic review of randomised and non-randomised controlled trials (RCTs) for effectiveness, and population-based case series for adverse events and fetal outcomes. Treatments: vitamins B6 and B12, ginger, acupressure/acupuncture, hypnotherapy, antiemetics, dopamine antagonists, 5-hydroxytryptamine receptor antagonists, intravenous (i.v.) fluids, corticosteroids, enteral and parenteral feeding or other novel treatment. Two reviewers extracted data and quality assessed studies. Results were narratively synthesised; planned meta-analysis was not possible due to heterogeneity and incomplete reporting. A simple economic evaluation considered the implied values of treatments.Results: Seventy-three studies (75 reports) met the inclusion criteria. For RCTs, 33 and 11 studies had a low and high risk of bias respectively. For the remainder (n = 20) it was unclear. The non-randomised studies (n = 9) were low quality. There were 33 separate comparators. The most common were acupressure versus placebo (n = 12); steroid versus usual treatment (n = 7); ginger versus placebo (n = 6); ginger versus vitamin B6 (n = 6); and vitamin B6 versus placebo (n = 4). There was evidence that ginger, antihistamines, metoclopramide (mild disease) and vitamin B6 (mild to severe disease) are better than placebo. Diclectin (R) [Duchesnay Inc.; doxylamine succinate (10 mg) plus pyridoxine hydrochloride (10 mg) slow release tablet] is more effective than placebo and ondansetron is more effective at reducing nausea than pyridoxine plus doxylamine. Diclectin before symptoms of NVP begin for women at high risk of severe NVP recurrence reduces risk of moderate/severe NVP compared with taking Diclectin once symptoms begin. Promethazine is as, and ondansetron is more, effective than metoclopramide for severe NVP/HG. I.v. fluids help correct dehydration and improve symptoms. Dextrose saline may be more effective at reducing nausea than normal saline. Transdermal clonidine patches may be effective for severe HG. Enteral feeding is effective but extreme method treatment for very severe symptoms. Day case management for moderate/severe symptoms is feasible, acceptable and as effective as inpatient care. For all other interventions and comparisons, evidence is unclear. The economic analysis was limited by lack of effectiveness data, but comparison of costs between treatments highlights the implications of different choices.Limitations: The main limitations were the quantity and quality of the data available.Conclusion: There was evidence of some improvement in symptoms for some treatments, but these data may not be transferable across disease se

Treatments for hyperemesis gravidarum and nausea and vomiting in pregnancy:A systematic review and economic assessment

Background: Nausea and vomiting in pregnancy (NVP) affects up to 85% of all women during pregnancy, but for the majority self-management suffices. For the remainder, symptoms are more severe and the most severe form of NVP – hyperemesis gravidarum (HG) – affects 0.3–1.0% of pregnant women. There is no widely accepted point at which NVP becomes HG. Objectives: This study aimed to determine the relative clinical effectiveness and cost-effectiveness of treatments for NVP and HG. Data sources: MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, PsycINFO, Commonwealth Agricultural Bureaux (CAB) Abstracts, Latin American and Caribbean Health Sciences Literature, Allied and Complementary Medicine Database, British Nursing Index, Science Citation Index, Social Sciences Citation Index, Scopus, Conference Proceedings Index, NHS Economic Evaluation Database, Health Economic Evaluations Database, China National Knowledge Infrastructure, Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effects were searched from inception to September 2014. References from studies and literature reviews identified were also examined. Obstetric Medicine was hand-searched, as were websites of relevant organisations. Costs came from NHS sources. Review methods: A systematic review of randomised and non-randomised controlled trials (RCTs) for effectiveness, and population-based case series for adverse events and fetal outcomes. Treatments: vitamins B6 and B12, ginger, acupressure/acupuncture, hypnotherapy, antiemetics, dopamine antagonists, 5-hydroxytryptamine receptor antagonists, intravenous (i.v.) fluids, corticosteroids, enteral and parenteral feeding or other novel treatment. Two reviewers extracted data and quality assessed studies. Results were narratively synthesised; planned meta-analysis was not possible due to heterogeneity and incomplete reporting. A simple economic evaluation considered the implied values of treatments. Results: Seventy-three studies (75 reports) met the inclusion criteria. For RCTs, 33 and 11 studies had a low and high risk of bias respectively. For the remainder (n = 20) it was unclear. The non-randomised studies (n = 9) were low quality. There were 33 separate comparators. The most common were acupressure versus placebo (n = 12); steroid versus usual treatment (n = 7); ginger versus placebo (n = 6); ginger versus vitamin B6 (n = 6); and vitamin B6 versus placebo (n = 4). There was evidence that ginger, antihistamines, metoclopramide (mild disease) and vitamin B6 (mild to severe disease) are better than placebo. Diclectin® [Duchesnay Inc.; doxylamine succinate (10 mg) plus pyridoxine hydrochloride (10 mg) slow release tablet] is more effective than placebo and ondansetron is more effective at reducing nausea than pyridoxine plus doxylamine. Diclectin before symptoms of NVP begin for women at high risk of severe NVP recurrence reduces risk of moderate/severe NVP compared with taking Diclectin once symptoms begin. Promethazine is as, and ondansetron is more, effective than metoclopramide for severe NVP/HG. I.v. fluids help correct dehydration and improve symptoms. Dextrose saline may be more effective at reducing nausea than normal saline. Transdermal clonidine patches may be effective for severe HG. Enteral feeding is effective but extreme method treatment for very severe symptoms. Day case management for moderate/severe symptoms is feasible, acceptable and as effective as inpatient care. For all other interventions and comparisons, evidence is unclear. The economic analysis was limited by lack of effectiveness data, but comparison of costs between treatments highlights the implications of different choices. Limitations: The main limitations were the quantity and quality of the data available. Conclusion: There was evidence of some improvement in symptoms for some treatments, but these data may not be transferable across disease severities. Methodologically sound and larger trials of the main therapies considered within the UK NHS are needed. Study registration: This study is registered as PROSPERO CRD42013006642. Funding: The National Institute for Health Research Health Technology Assessment programme

Cellulolytic Bacteria in the foregut of the dromedary camel (Camelus dromedarius)

Foregut digesta from five feral dromedary camels were inoculated into three different enrichment media: cotton thread, filter paper, and neutral detergent fiber. A total of 283 16S rRNA gene sequences were assigned to 33 operational taxonomic units by using 99% species-level identity. LIBSHUFF revealed significant differences in the community composition across all three libraries

Treatments for Hyperemesis Gravidarum and Nausea and Vomiting in Pregnancy

Importance Nausea and vomiting affects approximately 85% of pregnant women. The most severe form, hyperemesis gravidarum, affects up to 3% of women and can have significant adverse physical and psychological sequelae.Objective To summarize current evidence on effective treatments for nausea and vomiting in pregnancy and hyperemesis gravidarum.Evidence Review Databases were searched to June 8, 2016. Relevant websites and bibliographies were also searched. Titles and abstracts were assessed independently by 2 reviewers. Results were narratively synthesized; planned meta-analysis was not possible because of heterogeneity and incomplete reporting of findings.Findings Seventy-eight studies (n  = 8930 participants) were included: 67 randomized clinical trials (RCTs) and 11 nonrandomized studies. Evidence from 35 RCTs at low risk of bias indicated that ginger, vitamin B6, antihistamines, metoclopramide (for mild symptoms), pyridoxine-doxylamine, and ondansetron (for moderate symptoms) were associated with improved symptoms compared with placebo. One RCT (n = 86) reported greater improvements in moderate symptoms following psychotherapy (change in Rhodes score [range, 0 {no symptoms} to 40 {worst possible symptoms}], 18.76 [SD, 5.48] to 7.06 [SD, 5.79] for intervention vs 19.18 [SD, 5.63] to 12.81 [SD, 6.88] for comparator [P < .001]). For moderate-severe symptoms, 1 RCT (n = 60) suggested that pyridoxine-doxylamine combination taken preemptively reduced risk of recurrence of moderate-severe symptoms compared with treatment once symptoms begin (15.4% vs 39.1% [P < .04]). One RCT (n = 83) found that ondansetron was associated with lower nausea scores on day 4 than metoclopramide (mean visual analog scale [VAS] score, 4.1 [SD, 2.9] for ondansetron vs 5.7 [SD, 2.3] for metoclopramide [P = .023]) but not episodes of emesis (5.0 [SD, 3.1] vs 3.3 [SD, 3], respectively [P = .013]). Although there was no difference in trend in nausea scores over the 14-day study period, trend in vomiting scores was better in the ondansetron group (P = .042). One RCT (n = 159) found no difference between metoclopramide and promethazine after 24 hours (episodes of vomiting, 1 [IQR, 0-5] for metoclopramide vs 2 [IQR, 0-3] for promethazine [P = .81], VAS [0-10 scale] for nausea, 2 [IQR, 1-5] vs 2 [IQR, 1-4], respectively [P = .99]). Three RCTs compared corticosteroids with placebo or promethazine or metoclopramide in women with severe symptoms. Improvements were seen in all corticosteroid groups, but only a significant difference between corticosteroids vs metoclopramide was reported (emesis reduction, 40.9% vs 16.5% at day 2; 71.6% vs 51.2% at day 3; 95.8% vs 76.6% at day 7 [n = 40, P < .001]). For other interventions, evidence was limited.Conclusions and Relevance For mild symptoms of nausea and emesis of pregnancy, ginger, pyridoxine, antihistamines, and metoclopramide were associated with greater benefit than placebo. For moderate symptoms, pyridoxine-doxylamine, promethazine, and metoclopramide were associated with greater benefit than placebo. Ondansetron was associated with improvement for a range of symptom severity. Corticosteroids may be associated with benefit in severe cases. Overall the quality of evidence was low

A new search for distant radio galaxies in the Southern hemisphere -- III. Optical spectroscopy and analysis of the MRCR--SUMSS sample

We have compiled a sample of 234 ultra-steep-spectrum(USS)-selected radio sources in order to find high-redshift radio galaxies (HzRGs). The sample is in the southern sky at -40 deg < DEC < -30 deg which is the overlap region of the 408-MHz Revised Molonglo Reference Catalogue, 843-MHz Sydney University Molonglo Sky Survey (the MRCR--SUMSS sample) and the 1400-MHz NRAO VLA Sky Survey. This is the third in a series of papers on the MRCR--SUMSS sample. Here we present optical spectra from the ANU 2.3-m telescope, ESO New Technology Telescope and ESO Very Large Telescope for 52 of the identifications from Bryant et al. (2009, Paper II), yielding redshifts for 36 galaxies, 13 of which have z>2. We analyse the K-z distribution and compare 4-arcsec-aperture magnitudes with 64-kpc aperture magnitudes in several surveys from the literature; the MRCR--SUMSS sample is found to be consistent with models for 10^{11}-10^{12} solar mass galaxies. Dispersions about the fits in the K-z plot support passive evolution of radio galaxy hosts since z>3. By comparing USS-selected samples in the literature, we find that the resultant median redshift of the samples shown is not dependent on the flux density distribution or selection frequency of each sample. In addition, our finding that the majority of the radio spectral energy distributions remain straight over a wide frequency range suggests that a k-correction is not responsible for the success of USS-selection in identifying high redshift radio galaxies and therefore the steep radio spectra may be intrinsic to the source or a product of the environment. Two galaxies have been found to have both compact radio structures and strong self-absorption in the Ly-alpha line, suggesting they are surrounded by a dense medium...abridged.Comment: Accepted for MNRAS. 25 page

Renormalization approach for quantum-dot structures under strong alternating fields

We develop a renormalization method for calculating the electronic structure of single and double quantum dots under intense ac fields. The nanostructures are emulated by lattice models with a clear continuum limit of the effective-mass and single-particle approximations. The coupling to the ac field is treated non-perturbatively by means of the Floquet Hamiltonian. The renormalization approach allows the study of dressed states of the nanoscopic system with realistic geometries as well arbitrary strong ac fields. We give examples of a single quantum dot, emphasizing the analysis of the effective-mass limit for lattice models, and double-dot structures, where we discuss the limit of the well used two-level approximation.Comment: 6 pages, 7 figure

A fresh look at the evolution and diversification of photochemical reaction centers

In this review, I reexamine the origin and diversification of photochemical reaction centers based on the known phylogenetic relations of the core subunits, and with the aid of sequence and structural alignments. I show, for example, that the protein folds at the C-terminus of the D1 and D2 subunits of Photosystem II, which are essential for the coordination of the water-oxidizing complex, were already in place in the most ancestral Type II reaction center subunit. I then evaluate the evolution of reaction centers in the context of the rise and expansion of the different groups of bacteria based on recent large-scale phylogenetic analyses. I find that the Heliobacteriaceae family of Firmicutes appears to be the earliest branching of the known groups of phototrophic bacteria; however, the origin of photochemical reaction centers and chlorophyll synthesis cannot be placed in this group. Moreover, it becomes evident that the Acidobacteria and the Proteobacteria shared a more recent common phototrophic ancestor, and this is also likely for the Chloroflexi and the Cyanobacteria. Finally, I argue that the discrepancies among the phylogenies of the reaction center proteins, chlorophyll synthesis enzymes, and the species tree of bacteria are best explained if both types of photochemical reaction centers evolved before the diversification of the known phyla of phototrophic bacteria. The primordial phototrophic ancestor must have had both Type I and Type II reaction centers