Early postnatal injections of whole vaccines compared to placebo controls: Differential behavioural outcomes in mice.

The present study was designed to evaluate the possible effects of the paediatric vaccination schedule in the United States on the central nervous system in a murine model. We compared the impact of treatment with the whole vaccines versus true placebo control. Seventy-six pups were divided into three groups: two vaccinated groups and unvaccinated control. The two vaccinated groups were treated between 7 and 21 post-natal days either with one or three times of the vaccine doses per body weight as used in children between newborn and eighteen months of age. The post-vaccination development, neuromotor behaviours and neurobehavioural abnormalities (NBAs) were evaluated in all mouse groups during the 67 post-natal weeks of mouse age. Mouse body weight was affected only in the vaccinated females compared to males and control. Some NBAs such as decreased sociability, increased anxiety-like behaviours, and alteration of visual-spatial learning and memory were observed in vaccinated male and female mice compared to controls. The present study also shows a slower acquisition of some neonatal reflexes in vaccinated female mice compared to vaccinated males and controls. The observed neurodevelopmental alterations did not show a linear relationship with vaccine dose, suggesting that the single dose gave a saturated response. The outcomes seemed to be sex-dependent and transient with age.

Season's Effects on Some Clinical, Hematological Parameters and Blood Cortisol Level in Sedated Arabian Horses With Xylazine.

Influence of heat or cold stress in sedated animals is unclear and requires further investigations. The present study aimed to evaluate the season's effects on some clinical, hematological parameters and blood cortisol level in sedated Arabian horses with xylazine. Therefore, seven Arabian horses were used to investigate heart and respiratory rates, and capillary refill time and serum cortisol level were recorded before (0) and at 5, 15, 60, and 180 minutes postsedation. Heparinized venous samples were collected before (0) and 3 hours postsedation for analysis of hematological analysis. Arterial blood samples were collected before and 1 hour postsedation for arterial blood gases and electrolytes analysis. Repeated analysis of variance was performed (P < .05). Significant decreases have been observed in heart and respiratory rates at 5, 15, and 60 minutes postsedation in summer and only at 5 minutes postsedation in winter. Arterial oxygen pressure and arterial carbon dioxide pressure showed a significant decrease and increase, respectively at 1 hour postsedation in summer and winter. The serum cortisol levels were significantly higher in summer than in winter at 5, 15, and 60 minutes postsedation. In summer, the postsedation concentrations of cortisol did not change significantly than its values before sedation. However, in winter, the cortisol concentration decreased significantly at 5, 15, and 60 minutes postsedation compared with their value before sedation. The present study suggests that these season's effects on the sedated Arabian horses could take into consideration in xylazine-sedated Arabian horses.

Physical and chemical characterization of McIntyre Powder: An aluminum dust inhaled by miners to combat silicosis.

McIntyre Powder (MP) is a finely ground aluminum powder that was used between 1943 and 1979 as a prophylaxis for silicosis. Silicosis is a chronic lung disease caused by the inhalation of crystalline silica dust and was prevalent in the Canadian mining industry during this time period. The McIntyre Research Foundation developed, patented, and produced the MP and distributed it to licensees in Canada, the United States, Mexico, Chile, Belgian Congo, and Western Australia. In the province of Ontario, Canada it is estimated that at least 27,500 miners between 1943 and 1979 were exposed to MP. The present study was undertaken to examine the chemical and physical characteristics of two variations of MP (light grey and black). Chemical analyses (using X-ray Fluorescence and Inductively Coupled Plasma approaches) indicate that the black MP contains significantly higher concentrations of aluminum and metal impurities than the light grey MP (p < 0.001). X-ray diffractometry shows that while aluminum hydroxide dominates the aluminum speciation in both variations, the higher total aluminum content in the black MP is attributable to a greater proportion of elemental aluminum. Physical characterization (using electron microscopy, light microscopy, and dynamic light scattering) indicates that the light grey MP consists of particles ranging from 5 nm to 5 µm in diameter. Atomic Force Microscopy shows that the light grey MP particles in the nanoparticle range (<100 nm) have a mode between 5 and 10 nm. Consequently, it is possible that inhaled smaller MP nanoparticles may be transported via blood and lymph fluid circulation to many different organs including the brain. It is also possible for inhaled larger MP particles to deposit onto lung tissue and for potential health effects to arise from inflammatory responses through immune activation. This MP characterization will provide crucial data to help inform future toxicological, epidemiological, and biological studies of any long-term effects related to the inhalation of aluminum dust and nanomaterials.

Loading Amlodipine on Diamond Nanoparticles: A Novel Drug Delivery System.

BACKGROUND: Diamond nanoparticles (Nanodiamond) are biocompatible drug delivery platforms with outstanding surface properties. Their passage into the brain has been confirmed previously. Thus, nanodiamond could provide a drug delivery system to shuttle several drugs through the blood-brain barrier (BBB) which represents a real challenge for the effective delivery of several drugs into the brain. Amlodipine is a calcium channel blocker that cannot pass through BBB and may elicit neuroprotective effects to reverse calcium-induced excitotoxicity and mitochondrial dysfunction that underlie several neurologic disorders including Alzheimer's disease and stroke. AIM: The study aimed to investigate the loading of amlodipine on nanodiamond particles. METHODS: Nanodiamond particles were oxidized in a strong oxidizing acidic mixture of sulfuric and nitric acids. Adsorption of amlodipine on nanodiamond particles was achieved in alkaline pH using various concentrations of sodium hydroxide. The loaded amlodipine was determined by high-performance liquid chromatography and confirmed by Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy. RESULTS: The highest percentage (41%) of loaded amlodipine onto nanodiamond particles was achieved in alkaline medium using 2 mM NaOH at a corresponding pH of 8.5. Also, characteristic FTIR bands of amlodipine and nanodiamond were shown obviously in the nanodiamond-amlodipine conjugates. Moreover, the successful loading of amlodipine on diamond nanoparticles was confirmed by transmission electron microscopy. CONCLUSION: The present study demonstrates the successful loading of amlodipine onto nanodiamond particles. These findings offer a potential for applying diamond nanoparticles as a drug delivery system to shuttle amlodipine into the brain and open the door to deliver other similar drugs into the brain.

Vitamin D deficiency in elderly: Risk factors and drugs impact on vitamin D status.

INTRODUCTION: Vitamin D (VD) deficiency is a major public health problem worldwide. In spite of its high prevalence, particularly among elderly people, VD deficiency is still underestimated by many physicians. Increasingly, VD deficiency is associated with several known geriatric syndromes. METHODS: The study sample consisted of 125 patients, aged 75 years and older, admitted to the acute geriatric unit. The plausible association between the serum 25-hydroxyvitamin D [25(OH)D] level and patient age, sex, body mass index, renal function, cholecystectomy history, and the prescribed drugs had been investigated. The Fisher's exact test was used to conduct the statistical analysis of data. RESULTS: Surprisingly, furosemide treatment was correlated with normal 25(OH)D levels and an increased incidence of secondary hyperparathyroidism. Unlike the other four parameters mentioned above, our data showed that only the patient sex exhibited a significant association with 25(OH)D level as elderly males suffered from a serious VD deficiency as compared to elderly females. CONCLUSION: Old age is an independent risk factor for VD deficiency. The supplementary dose of VD should be precisely defined to achieve the optimal serum 25(OH)D level in elderly people. The definition of the normal serum 25(OH)D threshold in elderly furosemide-treated patients is worth of further studies.

Neuroprotective Effect of Nanodiamond in Alzheimer's Disease Rat Model: a Pivotal Role for Modulating NF-κB and STAT3 Signaling.

Current therapeutic approaches of Alzheimer's disease (AD) are symptomatic and of modest efficacy, and there is no available effective cure or prevention of AD; hence, the need arise to search for neuroprotective agents to combat AD. The current study aimed at investigating the neuroprotective effect of nanodiamond (ND), adamantine-based nanoparticles, in aluminum-induced cognitive impairment in rats, an experimental model of AD. AD was induced by aluminum chloride (17 mg/kg, p.o. for 6 weeks) and confirmed by Morris water maze and Y-maze behavioral tests. Biochemical and histological analyses of the hippocampus were also performed. Aluminum-treated rats showed behavioral, biochemical, and histological changes similar to those associated with AD. ND improved learning and memory and reversed histological alterations. At the molecular levels, ND mitigated the increase of hippocampal beta-amyloid (Aß42) and beta-site amyloid precursor protein cleaving enzyme-1 (BACE1) together with down-regulation of phosphorylated tau protein. It also modulated the excitatory glutamate neurotransmitter level. Furthermore, ND boosted the brain-derived neurotrophic factor (BDNF) and mitochondrial transcription factor-A (TFAM), suppressed the proinflammatory cytokine tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and curbed oxidative stress by hampering of inducible nitric oxide synthase (iNOS). Moreover, ND augmented the hippocampal levels of phosphorylated signal transducer and activator of transcription-3 (p-STAT3) and B cell leukemia/lymphoma-2 (Bcl-2) anti-apoptotic protein while diminished nuclear factor-kappaB (NF-κB) and caspase-3 (casp-3) expression. These findings indicate the protective effect of ND against memory deficits and AD-like pathological aberrations probably via modulating NF-kB and STAT3 signaling, effects mediated likely by modulating N-methyl-D-aspartate (NMDA) receptors.

Non-linear dose-response of aluminium hydroxide adjuvant particles: Selective low dose neurotoxicity.

Aluminium (Al) oxyhydroxide (Alhydrogel®), the main adjuvant licensed for human and animal vaccines, consists of primary nanoparticles that spontaneously agglomerate. Concerns about its safety emerged following recognition of its unexpectedly long-lasting biopersistence within immune cells in some individuals, and reports of chronic fatigue syndrome, cognitive dysfunction, myalgia, dysautonomia and autoimmune/inflammatory features temporally linked to multiple Al-containing vaccine administrations. Mouse experiments have documented its capture and slow transportation by monocyte-lineage cells from the injected muscle to lymphoid organs and eventually the brain. The present study aimed at evaluating mouse brain function and Al concentration 180days after injection of various doses of Alhydrogel® (200, 400 and 800µg Al/kg of body weight) in the tibialis anterior muscle in adult female CD1 mice. Cognitive and motor performances were assessed by 8 validated tests, microglial activation by Iba-1 immunohistochemistry, and Al level by graphite furnace atomic absorption spectroscopy. An unusual neuro-toxicological pattern limited to a low dose of Alhydrogel® was observed. Neurobehavioural changes, including decreased activity levels and altered anxiety-like behaviour, were observed compared to controls in animals exposed to 200µg Al/kg but not at 400 and 800µg Al/kg. Consistently, microglial number appeared increased in the ventral forebrain of the 200µg Al/kg group. Cerebral Al levels were selectively increased in animals exposed to the lowest dose, while muscle granulomas had almost completely disappeared at 6 months in these animals. We conclude that Alhydrogel® injected at low dose in mouse muscle may selectively induce long-term Al cerebral accumulation and neurotoxic effects. To explain this unexpected result, an avenue that could be explored in the future relates to the adjuvant size since the injected suspensions corresponding to the lowest dose, but not to the highest doses, exclusively contained small agglomerates in the bacteria-size range known to favour capture and, presumably, transportation by monocyte-lineage cells. In any event, the view that Alhydrogel® neurotoxicity obeys "the dose makes the poison" rule of classical chemical toxicity appears overly simplistic.

Highly delayed systemic translocation of aluminum-based adjuvant in CD1 mice following intramuscular injections.

Concerns regarding vaccine safety have emerged following reports of potential adverse events in both humans and animals. In the present study, alum, alum-containing vaccine and alum adjuvant tagged with fluorescent nanodiamonds were used to evaluate i) the persistence time at the injection site, ii) the translocation of alum from the injection site to lymphoid organs, and iii) the behavior of adult CD1 mice following intramuscular injection of alum (400 µg Al/kg). Results showed for the first time a strikingly delayed systemic translocation of adjuvant particles. Alum-induced granuloma remained for a very long time in the injected muscle despite progressive shrinkage from day 45 to day 270. Concomitantly, a markedly delayed translocation of alum to the draining lymph nodes, major at day 270 endpoint, was observed. Translocation to the spleen was similarly delayed (highest number of particles at day 270). In contrast to C57BL/6J mice, no brain translocation of alum was observed by day 270 in CD1 mice. Consistently neither increase of Al cerebral content, nor behavioral changes were observed. On the basis of previous reports showing alum neurotoxic effects in CD1 mice, an additional experiment was done, and showed early brain translocation at day 45 of alum injected subcutaneously at 200 µg Al/kg. This study confirms the striking biopersistence of alum. It points out an unexpectedly delayed diffusion of the adjuvant in lymph nodes and spleen of CD1 mice, and suggests the importance of mouse strain, route of administration, and doses, for future studies focusing on the potential toxic effects of aluminum-based adjuvants.

Fluorescent nanodiamonds as a relevant tag for the assessment of alum adjuvant particle biodisposition.

BACKGROUND: Aluminum oxyhydroxide (alum) is a crystalline compound widely used as an immunologic adjuvant of vaccines. Concerns linked to alum particles have emerged following recognition of their causative role in the so-called macrophagic myofasciitis (MMF) lesion in patients with myalgic encephalomyelitis, revealing an unexpectedly long-lasting biopersistence of alum within immune cells and a fundamental misconception of its biodisposition. Evidence that aluminum-coated particles phagocytozed in the injected muscle and its draining lymph nodes can disseminate within phagocytes throughout the body and slowly accumulate in the brain further suggested that alum safety should be evaluated in the long term. However, lack of specific staining makes difficult the assessment of low quantities of bona fide alum adjuvant particles in tissues. METHODS: We explored the feasibility of using fluorescent functionalized nanodiamonds (mfNDs) as a permanent label of alum (Alhydrogel(®)). mfNDs have a specific and perfectly photostable fluorescence based on the presence within the diamond lattice of nitrogen-vacancy centers (NV centers). As the NV center does not bleach, it allows the microspectrometric detection of mfNDs at very low levels and in the long-term. We thus developed fluorescent nanodiamonds functionalized by hyperbranched polyglycerol (mfNDs) allowing good coupling and stability of alum:mfNDs (AluDia) complexes. Specificities of AluDia complexes were comparable to the whole reference vaccine (anti-hepatitis B vaccine) in terms of particle size and zeta potential. RESULTS: In vivo, AluDia injection was followed by prompt phagocytosis and AluDia particles remained easily detectable by the specific signal of the fND particles in the injected muscle, draining lymph nodes, spleen, liver and brain. In vitro, mfNDs had low toxicity on THP-1 cells and AluDia showed cell toxicity similar to alum alone. Expectedly, AluDia elicited autophagy, and allowed highly specific detection of small amounts of alum in autophagosomes. CONCLUSIONS: The fluorescent nanodiamond technology is able to overcome the limitations of previously used organic fluorophores, thus appearing as a choice methodology for studying distribution, persistence and long-term neurotoxicity of alum adjuvants and beyond of other types of nanoparticles.

Biopersistence and brain translocation of aluminum adjuvants of vaccines.

Aluminum oxyhydroxide (alum) is a crystalline compound widely used as an immunological adjuvant of vaccines. Concerns linked to the use of alum particles emerged following recognition of their causative role in the so-called macrophagic myofasciitis (MMF) lesion detected in patients with myalgic encephalomyelitis/chronic fatigue/syndrome. MMF revealed an unexpectedly long-lasting biopersistence of alum within immune cells in presumably susceptible individuals, stressing the previous fundamental misconception of its biodisposition. We previously showed that poorly biodegradable aluminum-coated particles injected into muscle are promptly phagocytosed in muscle and the draining lymph nodes, and can disseminate within phagocytic cells throughout the body and slowly accumulate in brain. This strongly suggests that long-term adjuvant biopersistence within phagocytic cells is a prerequisite for slow brain translocation and delayed neurotoxicity. The understanding of basic mechanisms of particle biopersistence and brain translocation represents a major health challenge, since it could help to define susceptibility factors to develop chronic neurotoxic damage. Biopersistence of alum may be linked to its lysosome-destabilizing effect, which is likely due to direct crystal-induced rupture of phagolysosomal membranes. Macrophages that continuously perceive foreign particles in their cytosol will likely reiterate, with variable interindividual efficiency, a dedicated form of autophagy (xenophagy) until they dispose of alien materials. Successful compartmentalization of particles within double membrane autophagosomes and subsequent fusion with repaired and re-acidified lysosomes will expose alum to lysosomal acidic pH, the sole factor that can solubilize alum particles. Brain translocation of alum particles is linked to a Trojan horse mechanism previously described for infectious particles (HIV, HCV), that obeys to CCL2, signaling the major inflammatory monocyte chemoattractant.

Unique growth pattern of human mammary epithelial cells induced by polymeric nanoparticles.

Due to their unique properties, engineered nanoparticles (NPs) have found broad use in industry, technology, and medicine, including as a vehicle for drug delivery. However, the understanding of NPs' interaction with different types of mammalian cells lags significantly behind their increasing adoption in drug delivery. In this study, we show unique responses of human epithelial breast cells when exposed to polymeric Eudragit® RS NPs (ENPs) for 1-3 days. Cells displayed dose-dependent increases in metabolic activity and growth, but lower proliferation rates, than control cells, as evidenced in tetrazolium salt (WST-1) and 5-bromo-2'-deoxyuridine (BrdU) assays, respectively. Those effects did not affect cell death or mitochondrial fragmentation. We attribute the increase in metabolic activity and growth of cells culture with ENPs to three factors: (1) high affinity of proteins present in the serum for ENPs, (2) adhesion of ENPs to cells, and (3) activation of proliferation and growth pathways. The proteins and genes responsible for stimulating cell adhesion and growth were identified by mass spectrometry and Microarray analyses. We demonstrate a novel property of ENPs, which act to increase cell metabolic activity and growth and organize epithelial cells in the epithelium as determined by Microarray analysis.