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Highlights: [•] Thiomersal was determined on line using FI-MW/UV-CVGAFS. [•] MW/UV allows a “green” on line oxidation of organic mercury to HgII. [•] Each measure requires less than 5min with a LOD of 3ngmL−1 (as mercury). [•] Hg concentration in commercial ophthalmic solutions ranges between 7.5 and 59.0μgmL−1. [Copyright &y& Elsevier]

Background: The European baseline series (EBS) of contact allergens is subject to change. An allergen is considered for inclusion when routine patch testing of patients with suspected contact dermatitis results in ≥0.5% prevalence rate., Objectives: We aimed to determine the frequency of sensitizations to 30 EBS allergens and 10 locally added allergens. Additionally, we assessed the strength and evolution of reactions to all tested allergens and co-reactivity of additional allergens., Methods: Patch testing with our baseline series of 40 allergens was done in 748 consecutive adults. Tests were applied to the upper back and removed by patients after 48 h. Readings were done on Day 3 (D3) and D6 or D7 (D6/7). Positive reactions fulfilled the criteria of at least one plus (+) reaction. A retrospective analysis was done., Results: Eight allergens not listed in the EBS had ≥0.5% prevalence rate (i.e., cocamidopropyl betaine, thiomersal, disperse blue mix 106/124, 2-bromo-2-nitropropane-1,3-diol, diazolidinyl urea, propylene glycol, Compositae mix II and dexamethasone-21-phosphate), and 16.6% of positive reactions would have been missed without D6/7 readings., Conclusion: We propose further studies to evaluate whether cocamidopropyl betaine, disperse blue mix 106/124, 2-bromo-2-nitropropane-1,3-diol, diazolidinyl urea and Compositae mix II need to be added to the EBS., (© 2022 The Authors. Contact Dermatitis published by John Wiley & Sons Ltd.)

Background: Cosmetic contact dermatitis (CCD) is a very common cosmetic adverse reaction, but there are few reports of adverse reactions to breast enhancement cream., Methods: We reported a case of adverse skin reactions after applying a cosmetic cream and performed patch tests of cosmetic series and cosmetic product., Results: After drug treatment, the patient's symptoms improved significantly. The cosmetic series patch test showed that she was allergic to thimerosal, and the cosmetic product patch also showed positive., Conclusions: The adverse reactions of dermatologists to cosmetics cannot be ignored, and it is suggested that in addition to common skin care products, the safety of other functional products should also be concerned., (© 2022 Wiley Periodicals LLC.)

Introduction: Outcome reporting bias in vaccine studies is a widespread problem among all researchers who have a tendency to report selective results and conclusions that support their beliefs and values or those of sponsoring agencies. Especially during the COVID-19 pandemic, this bias surfaced through the unprecedented proliferation of conflicting vaccine studies. Many researchers strongly recommend and report on the safety and effectiveness of the COVID-19 vaccine. Those researchers who embrace the COVID-19 vaccine and vaccines, in general, are often dismissive of other researchers who present views that differ from medical orthodoxy and oppose medical consensus., Methods: The aim of this analysis is to critically evaluate seven vaccine studies using qualitative and/or quantitative approaches to identify outcome reporting bias and assess its potential impact on the stated conclusions that align with medical consensus. Four studies claim to have found no association between autism and (a) blood levels of mercury, (b) measles, mumps, and rubella (MMR) vaccine, and (c) thimerosal-containing vaccines. Three other studies claim no association exists between infant mortality rate and the number of vaccine doses, universal varicella vaccination and herpes zoster, and pandemic influenza vaccines and fetal losses., Results: The presence of outcome reporting bias and independent reanalysis demonstrated an impact on both the direction and magnitude of the observed effect - raising questions concerning the robustness of the original study design and conclusions and challenging the current medical consensus. Medical consensus has exonerated vaccines as having any causal relationship to autism spectrum disorders (ASDs), yet no other reasonable cause has been proposed. Medical consensus attributes significant ASD increases to better case ascertainment and broadened clinical diagnosis. According to 2018 data, an estimated 1 in 44 eight-year-olds has been identified with ASD. From 1990 to 2019, there have been an estimated two million new cases of ASD in the US, with lifetime social costs exceeding $7 trillion (in 2019 dollars). Can perpetuating medical consensus impede the advancement of public health? Or has it already done so?, Conclusions:  Conflicts of interest (e.g., financial) that abound between health regulatory agencies and the pharmaceutical industry impact what is ultimately reckoned as medical consensus. Outcome reporting bias that is inherent to all researchers to some degree, obscures medical and scientific truth. Advancement of public health requires that researchers have integrity and an openness and willingness to collaborate to resolve contradictory findings. In fact, it is usually through meticulous, rigorous, scientific investigation of contradictory findings that medical science has advanced and contributed to improvements in public health - since medical consensus and orthodoxy can be incorrect., Competing Interests: Gary S. Goldman is an unpaid consultant to the non-profit Physicians for Informed Consent., (Copyright © 2022, Goldman et al.)

Positive Montenegro's skin test is a delayed type hypersensitivity reaction widely used as indicative of previous infection with Leishmania in both humans and dogs. Montenegro's antigen consists of a crude Leishmania antigen solution, usually containing thimerosal as preserving agent. In this work it is shown that a large proportion of dogs (11 out of 56) examined in an endemic area of leishmaniasis presented induration at the site of injection of a diluent containing thimerosal alone. This clearly demonstrates that thimerosal leads to a high number of false positive skin reactions in dogs and that its use in Montenegro's skin test antigenic preparations should be avoided.

Abstract: The object of this study was to evaluate the potential of a recently developed preactivated thiolated pectin derivative as mucoadhesive excipient in drug delivery to the gastric cavity. Pectin (Pec) was chemically modified with l-cysteine (Cys). The free thiol groups of resulting thiomer were activated with 2-mercaptonicotinic acid (MNA) in order to improve stability and reactivity of attached thiol groups over a broad pH range. Multiunit dosage form properties of the resulting conjugate (Pec–Cys–MNA) were compared to unmodified pectin and the intermediate thiolated using rosuvastatin calcium as a model drug in loaded minitablets. Obtained results were compared with unmodified pectin and the intermediate thiolated pectin. Approximately half of attached thiol groups (507?mol/g polymer) have been preactivated. Minitablets were evaluated regarding mucoadhesive properties, hardness, disintegration behavior, swelling characteristics and release of rosuvastatin calcium. Mediated by covalent bonds between the polymer and cysteine-rich subdomains in mucus, total work of adhesion increased more than 5-fold. The modification had no impact on hardness of compressed tablets but implementation of the aromatic ligand went along with reduction in hydrophilic properties. Disintegration time was prolonged more than 2-fold while water uptake capacity increased. Weight gain for Pec–Cys–MNA was at least 16-fold. Further, a sustained release of rosuvastatin calcium over 36h was determined. Neither biodegradability nor CaCo-2 cell viability was affected. The study shows that Pec–Cys–MNA is a promising excipient for the development of mucoadhesive gastric dosage form. [Copyright &y& Elsevier]

Background: This study was undertaken to determine the effect of thimerosal on the neurodevelopment of premature rats. Methods: Thimerosal was injected into premature SD rats at a dose of 32.8, 65.6, 98.4 or 131.2 μg/kg on postnatal day 1. Expression of dopamine D4 receptor (DRD4) and serotonin 2A receptor (5-HT2AR), apoptosis in the prefrontal cortex on post-injection day 49, and learning and memory function were studied and compared with those in a control group injected with saline. Results: Expression of DRD4 and 5-HT2AR and learning function decreased, and apoptosis increased significantly in the 131.2 μg/kg group ( P<0.001). Memory function was significantly impaired by 65.6 ( P<0.05), 98.4 and 131.2 μg/kg ( P<0.001). Conclusions: The negative adverse consequences on neurodevelopment observed in the present study are consistent with previous studies; this study raised serious concerns about adverse neurodevelopmental disorder such as autism in humans following the ongoing worldwide routine administration of thimerosalcontaining vaccines to infants. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a hazardous chemical that accumulates in many cells and tissues, thereby producing toxicity. The kidney is a key target organ for Hg accumulation and toxicity. The contributing factors to Hg accumulation in humans include: (1) elemental and inorganic Hg exposure, often occurring by inhalation of Hg vapors; (2) exposure to methyl Hg (meHg), for example, through contaminated seafood; and (3) exposure to ethyl mercury (etHg) via thimerosal-containing vaccines. Systematic investigations on the toxic effects of etHg/thimerosal on the nervous system were carried out, and etHg/thimerosal emerged as a possible risk factor for autism and other neurodevelopmental disorders. There is, however, little known about the mechanisms and molecular interactions underlying toxicity of etHg/thimerosal in the kidney, which is the focus of the current review. Susceptible populations such as infants, pregnant women, and the elderly are exposed to etHg through thimerosal-containing vaccines, and in-depth study of the potential adverse effects on the kidney is needed. In general, toxicity occurring in association with different forms of Hg is related to: intracellular thiol metabolism and oxidative stress reactions; mitochondrial function; intracellular distribution and build-up of calcium; apoptosis; expression of stress proteins; and also interaction with the cytoskeleton. Available evidence for the etHg-induced toxicity in the kidney was examined, and the main mechanisms and molecular interactions of cytotoxicity of etHg/thimerosal exposure in kidney described. Such accumulating knowledge may help to indicate molecular pathways that, if modulated, may better handle Hg-mediated toxicity. [ABSTRACT FROM PUBLISHER]

ABSTRACT Ethylmercury (etHg) is derived from the metabolism of thimerosal (o-carboxyphenyl-thio-ethyl-sodium salt), which is the most widely used form of organic mercury. Because of its application as a vaccine preservative, almost every human and animal (domestic and farmed) that has been immunized with thimerosal-containing vaccines has been exposed to etHg. Although methylmercury (meHg) is considered a hazardous substance that is to be avoided even at small levels when consumed in foods such as seafood and rice (in Asia), the World Health Organization considers small doses of thimerosal safe regardless of multiple/repetitive exposures to vaccines that are predominantly taken during pregnancy or infancy. We have reviewed in vitro and in vivo studies that compare the toxicological parameters among etHg and other forms of mercury (predominantly meHg) to assess their relative toxicities and potential to cause cumulative insults. In vitro studies comparing etHg with meHg demonstrate equivalent measured outcomes for cardiovascular, neural and immune cells. However, under in vivo conditions, evidence indicates a distinct toxicokinetic profile between meHg and etHg, favoring a shorter blood half-life, attendant compartment distribution and the elimination of etHg compared with meHg. EtHg's toxicity profile is different from that of meHg, leading to different exposure and toxicity risks. Therefore, in real-life scenarios, a simultaneous exposure to both etHg and meHg might result in enhanced neurotoxic effects in developing mammals. However, our knowledge on this subject is still incomplete, and studies are required to address the predictability of the additive or synergic toxicological effects of etHg and meHg (or other neurotoxicants). Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the number of inactivated-influenza vaccine–related spontaneous abortion and stillbirth (SB) reports in the Vaccine Adverse Event Reporting System (VAERS) database during three consecutive flu seasons beginning 2008/2009 and assess the relative fetal death reports associated with the two-vaccine 2009/2010 season. The VAERS database was searched for reports of fetal demise following administration of the influenza vaccine/vaccines to pregnant women. Utilization of an independent surveillance survey and VAERS, two-source capture–recapture analysis estimated the reporting completeness in the 2009/2010 flu season. Capture–recapture demonstrated that the VAERS database captured about 13.2% of the total 1321 (95% confidence interval (CI): 815–2795) estimated reports, yielding an ascertainment-corrected rate of 590 fetal-loss reports per million pregnant women vaccinated (or 1 per 1695). The unadjusted fetal-loss report rates for the three consecutive influenza seasons beginning 2008/2009 were 6.8 (95% CI: 0.1–13.1), 77.8 (95% CI: 66.3–89.4), and 12.6 (95% CI: 7.2–18.0) cases per million pregnant women vaccinated, respectively. The observed reporting bias was too low to explain the magnitude increase in fetal-demise reporting rates in the VAERS database relative to the reported annual trends. Thus, a synergistic fetal toxicity likely resulted from the administration of both the pandemic (A-H1N1) and seasonal influenza vaccines during the 2009/2010 season. [ABSTRACT FROM AUTHOR]

IP3R (IP3 [inositol 1,4,5-trisphosphate] receptors) and ryanodine receptors are the most widely expressed intracellular Ca2+ channels and both are regulated by thiol reagents. In DT40 cells stably expressing single subtypes of mammalian IP3R, low concentrations of thimerosal (also known as thiomersal), which oxidizes thiols to form a thiomercurylethyl complex, increased the sensitivity of IP3-evoked Ca2+ release via IP3R1 and IP3R2, but inhibited IP3R3. Activation of IP3R is initiated by IP3 binding to the IBC (IP3-binding core; residues 224-604) and proceeds via re-arrangement of an interface between the IBC and SD (suppressor domain; residues 1-223). Thimerosal (100 μM) stimulated IP3 binding to the isolated NT (N-terminal; residues 1-604) of IP3R1 and IP3R2, but not to that of IP3R3. Binding of a competitive antagonist (heparin) or partial agonist (dimeric-IP3) to NT1 was unaffected by thiomersal, suggesting that the effect of thimerosal is specifically related to IP3R activation. IP3 binding to NT1 in which all cysteine residues were replaced by alanine was insensitive to thimerosal, so too were NT1 in which cysteine residues were replaced in either the SD or IBC. This demonstrates that thimerosal interacts directly with cysteine in both the SD and IBC. Chimaeric proteins in which the SD of the IP3R was replaced by the structurally related A domain of a ryanodine receptor were functional, but thimerosal inhibited both IP3 binding to the chimaeric NT and IP3-evoked Ca2+ release from the chimaeric IP3R. This is the first systematic analysis of the effects of a thiol reagent on each IP3R subtype. We conclude that thimerosal selectively sensitizes IP3R1 and IP3R2 to IP3 by modifying cysteine residues within both the SD and IBC and thereby stabilizing an active conformation of the receptor. [ABSTRACT FROM AUTHOR]

Vaccination is one of the most important public health interventions in the reduction childhood morbidity and mortality. Thimerosal is an organic mercury compound used as preservante in multi-dose vials. Often in Peru, there are waves of controversy about the safety of this type of vaccines, mainly arguing that there is an association between them and autism. As a result of these controversies, there have been some voices asking for laws banning thimerosal-containing vaccines, which would have a large impact in costs and the logistic aspects of the public vaccination programs. The aim of this article is to review the literature for the main controversies about thimerosal in vaccines and its supposed association to autism. We made an historical review about these controversies given the available scientific evidence and the statements from important international organizations. We concluded that the current available evidence do not support an association between thimerosal and childhood neurodevelopmental disorders, such as autism. [ABSTRACT FROM AUTHOR]

[Ca2+]i signaling regulates sperm motility, enabling switching between functionally different behaviors that the sperm must employ as it ascends the female tract and fertilizes the oocyte. We report that different behaviors in human sperm are recruited according to the Ca2+ signaling pathway used. Activation of CatSper (by raising pHi or stimulating with progesterone) caused sustained [Ca2+]i elevation but did not induce hyperactivation, the whiplash-like behavior required for progression along the oviduct and penetration of the zona pellucida. In contrast, penetration into methylcellulose (mimicking penetration into cervical mucus or cumulus matrix) was enhanced by activation of CatSper. NNC55-0396, which abolishes CatSper currents in human sperm, inhibited this effect. Treatment with 5μM thimerosal to mobilize stored Ca2+ caused sustained [Ca2+]i elevation and induced strong, sustained hyperactivation that was completely insensitive to NNC55- 0396. Thimerosal had no effect on penetration into methylcellulose. 4-Aminopyridine, a powerful modulator of sperm motility, both raised pHi and mobilized Ca2+ stored in sperm (and from microsomal membrane preparations). 4-Aminopyridineinduced hyperactivation even in cells suspended in Ca2+-depleted medium and also potentiated penetration into methylcellulose. The latter effect was sensitive to NNC55-039, but induction of hyperactivation was not. We conclude that these two components of the [Ca2+]i signaling apparatus have strikingly different effects on sperm motility. Furthermore, since stored Ca2+ at the sperm neck can be mobilized by Ca2+-induced Ca2+ release, we propose that CatSper activation can elicit functionally different behaviors according to the sensitivity of the Ca2+store, which may be regulated by capacitation and NO from the cumulus. [ABSTRACT FROM AUTHOR]

Abstract: Thimerosal, an organomercury compound, has been widely used as a preservative. Therefore, concerns have been raised about its neurotoxicity. We recently demonstrated perturbation of early serotonergic development by prenatal exposure to thimerosal (Ida-Eto et al. (2011) [11]). Here, we investigated whether prenatal thimerosal exposure causes persistent impairment after birth. Analysis on postnatal day 50 showed significant increase in hippocampal serotonin following thimerosal administration on embryonic day 9. Furthermore, not only serotonin, striatal dopamine was significantly increased. These results indicate that embryonic exposure to thimerosal produces lasting impairment of brain monoaminergic system, and thus every effort should be made to avoid the use of thimerosal. [Copyright &y& Elsevier]

The acetate derivatives of coumarin exhibited a prominent turn-on type signaling behavior toward BO3− ions over other common anions. Signaling is based on the selective deprotection of acetate groups by perborate, which resulted in significant fluorogenic signaling in an acetate buffered solution (pH 5.0). Interestingly, the detection process makes the raw material of 7-hydroxycoumarin regenerate, and the probe could be applied for the detection of BO3− of thimerosal. Furthermore, the optical properties of the probe and its BO3−-induced product were theoretically studied based on density functional theory (DFT) and the time-dependent DFT (TDDFT) explored at the B3LYP/6-311+G (d, p) level. [ABSTRACT FROM AUTHOR]

The role of thimerosal containing vaccines in the development of autism spectrum disorder (ASD) has been an area of intense debate, as has the presence of mercury dental amalgams and fish ingestion by pregnant mothers. We studied the effects of thimerosal on cell proliferation and mitochondrial function from B-lymphocytes taken from individuals with autism, their nonautistic twins, and their nontwin siblings. Eleven families were examined and compared to matched controls. B-cells were grown with increasing levels of thimerosal, and various assays (LDH, XTT, DCFH, etc.) were performed to examine the effects on cellular proliferation and mitochondrial function. A subpopulation of eight individuals (4 ASD, 2 twins, and 2 siblings) from four of the families showed thimerosal hypersensitivity, whereas none of the control individuals displayed this response. The thimerosal concentration required to inhibit cell proliferation in these individuals was only 40% of controls. Cells hypersensitive to thimerosal also had higher levels of oxidative stress markers, protein carbonyls, and oxidant generation. This suggests certain individuals with a mild mitochondrial defect may be highly susceptible to mitochondrial specific toxins like the vaccine preservative thimerosal. [ABSTRACT FROM AUTHOR]

Background: Autism spectrum disorder (ASD) is identified by developmental deficits that lead to repetitive/stereotypic patterns of behavior and impaired social interactions. Studies have been indicated that exercise can decrease stereotypic behaviors in animal models of ASD. This research was designed to discover the effects of different models of forced exercise on stereotypical behaviors in a rat model of ASD induced by thimerosal (THIM). Materials and Methods: Fifty-six male Wistar rats were divided into eight groups. The rats were received saline (1 ml/kg) or THIM (300 μg Hg/kg) by four intramuscular injections on 7, 9, 11, and 15 postnatal days. The rats were also treated by several protocols of treadmill exercise, including non-sedentary, sedentary, protocol 1, protocol 2, and a combination of protocols 1 and 2. Results: Our study showed that THIM decreased the grooming time compared to the control group. Moreover, protocol 2 exercise significantly decreased grooming time in stranger zone 2 compared to the THIM group. Conclusions: Our results showed that stereotypical behaviors exaggerated by THIM and moderate exercise could improve ASD-associated behaviors in the THIM-treated rats. Hence, moderate exercise may be a useful protocol for the treatment of ASD., (Copyright© 2022, Galen Medical Journal.)

Although it is widely recognized that disruption of ALS3 reduces the invasion of Candida albicans germ tubes into mammalian oral epithelial cells, the mechanism of this interaction was unexplored. C. albicans strains with structurally informed mutations to remove adhesive activity of the peptide-binding cavity (PBC) or aggregative activity mediated by the amyloid-forming region (AFR) were assessed for their ability to invade cultured human oropharyngeal epithelial cells. Initial assays utilized untreated fungal and epithelial cells. Subsequent work used epithelial cells treated with cytochalasin D and C. albicans cells treated with thimerosal to investigate invasion mediated by active penetration of germ tubes and epithelial cell induced endocytosis, respectively. Results demonstrated the importance of the PBC for the invasion process: loss of PBC function resulted in the same reduced-invasion phenotype as a C. albicans strain that did not produce Als3 on its surface. Invasion via active penetration was particularly compromised without PBC function. Loss of AFR function produced a wild-type phenotype in the untreated and thimerosal-treated invasion assays but increased invasion in cytochalasin D-treated epithelial cells. In previous work, reduced AFR-mediated Als3 aggregation increased C. albicans adhesion to cultured epithelial cell monolayers, presumably via increased PBC accessibility for ligand binding. Collectively, results presented here demonstrate that Als3 PBC-mediated adhesion is integral to its invasive function. These new data add to the mechanistic understanding of the role of Als3 in C. albicans invasion into mammalian oral epithelial cells., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Oh and Hoyer.)

Neonates and nursing infants are special with regard to immune development and vulnerability to infectious diseases. Although breast-feeding is essential to modulate and prime immune defenses, vaccines (an interventional prophylaxis) are crucial to prevent and control infectious diseases. During nursing, the type of feeding influences infants' natural defenses (including gut colonization) and their response to vaccines, both through cell-mediated immunity and specific antibody production. Given the variety and combination of vaccine components (antigens and excipients, preservative thimerosal, and aluminum adjuvants) and route of administration, there is a need to examine the role of infant feeding practices in intended and nonintended outcomes of vaccination. Maternal factors related to milk constituents (nutrients and pollutants) and feeding practices can affect response to vaccines. Collectively, studies that compared type of feeding (or used breast-feeding-adjusted statistical models) showed significant influence on some vaccines taken during infancy. Nurslings deprived of the full benefit of breast-feeding could have altered immune responses affecting vaccine outcome. In the absence of studies elucidating neurodevelopment (including excitoxicity) and immunotoxicity issues, vaccination practices should promote and support breast-feeding. [ABSTRACT FROM AUTHOR]

Abstract: Background: Despite the common use of Thimerosal as a preservative in childhood vaccines since the 1930s, there are not many studies on ethylmercury toxicokinetics and toxicodynamics in infants. The knowledge of ethylmercury''s potential adverse effects is derived mostly from parallel methylmercury research or from animal and theoretical models. Aim of the study: This study was designed to examine the relationship between neonatal exposure to Thimerosal-containing vaccine (TCV) and child development. Material and methods: The study sample consisted of 196 infants born between January 2001 and March 2003 to mothers attending ambulatory prenatal clinics in the first and second trimesters of pregnancy in Krakow. Vaccination history (date and the type of the vaccine) was extracted from physicians'' records. Child development was assessed using the Bayley Scales of Infant Development (BSID-II) measured in one-year intervals over 3years. General Linear Model (GLM) and Generalized Estimating Equation (GEE) models adjusted for potential confounders were used to assess the association. Results: An adverse effect of neonatal TCV exposure was observed for the psychomotor development index (PDI) only in the 12th and 24th months of life (β=−6.44, p<0.001 and β=−5.89, p<0.001). No significant effect of neonatal TCV exposure was found in the 36th month. The overall deficit in the PDI attributable to neonatal TCV exposure measured over the course of the three-year follow-up (GEE) was significantly higher in TCV group (β=−4.42, p=0.001). MDI scores did not show the adverse association with neonatal TCV exposure. [Copyright &y& Elsevier]

We have compared the performance of two Troponin-C-based calcium FRET sensors using fluorescence lifetime read-outs. The first sensor, TN-L15, consists of a Troponin-C fragment inserted between CFP and Citrine while the second sensor, called mTFP-TnC-Cit, was realized by replacing CFP in TN-L15 with monomeric Teal Fluorescent Protein (mTFP1). Using cytosol preparations of transiently transfected mammalian cells, we have measured the fluorescence decay profiles of these sensors at controlled concentrations of calcium using time-correlated single photon counting. These data were fitted to discrete exponential decay models using global analysis to determine the FRET efficiency, fraction of donor molecules undergoing FRET and calcium affinity of these sensors. We have also studied the decay profiles of the donor fluorescent proteins alone and determined the sensitivity of the donor lifetime to temperature and emission wavelength. Live-cell fluorescence lifetime imaging (FLIM) of HEK293T cells expressing each of these sensors was also undertaken. We confirmed that donor fluorescence of mTFP-TnC-Cit fits well to a two-component decay model, while the TN-L15 lifetime data was best fitted to a constrained four-component model, which was supported by phasor analysis of the measured lifetime data. If the constrained global fitting is employed, the TN-L15 sensor can provide a larger dynamic range of lifetime readout than the mTFP-TnC-Cit sensor but the CFP donor is significantly more sensitive to changes in temperature and emission wavelength compared to mTFP and, while the mTFP-TnC-Cit solution phase data broadly agreed with measurements in live cells, this was not the case for the TN-L15 sensor. Our titration experiment also indicates that a similar precision in determination of calcium concentration can be achieved with both FRET biosensors when fitting a single exponential donor fluorescence decay model to the fluorescence decay profiles. We therefore suggest that mTFP-based probes are more suitable for FLIM experiments than CFP-based probes. [ABSTRACT FROM AUTHOR]

Abstract: Recently, a single nucleotide polymorphism (SNP) of the inositol 1,4,5-triphosphate kinase C (ITPKC), rs28493229, was found to passively confer susceptibility for Kawasaki syndrome (KS) and subsequent coronary arterial lesions. This association is believed to be the result of defective phosphorylation of inositol 1,4,5-triphosphate (IP3), which releases calcium from intracellular stores, resulting from reduced genetic expression of ITPKC in carriers of the SNP. Reduced ITPKC activity would increase IP3 levels, and thus, increase calcium release. We hypothesized that an environmental agent which influences IP3-mediated calcium release is potentiated by the ITPKC SNP. This led us to an attractive candidate, thimerosal, an organomercurial medical preservative still used in several pediatric vaccines. Thimerosal is well-known to sensitize IP3 receptors via its induction of oxidative stress, resulting in enhanced release of intracellular calcium with distinctive consequences for various cell types. Dysregulated calcium signaling in T cells and other immune cells can result in autoimmunity, while hyperpolarization of vascular smooth muscle cells secondary to the stimulation of calcium-activated potassium channels can result in increased vascular permeability and arterial relaxation. We propose that ITPKC susceptibility in KS is related to its synergy with environmental triggers, such as thimerosal, which alter calcium homeostasis and promote oxidative stress. Therefore, carriers of the ITPKC SNP are more susceptible to thimerosal-induced autoimmunity and coronary arterial lesions observed in KS. This would explain why only a susceptible subset of children develops KS although pediatric thimerosal exposure is nearly universal due to vaccination. As was experienced with the infantile acrodynia epidemic, only 1 in 500 children developed the disease although pediatric mercury exposure was nearly ubiquitous due to the use calomel teething powders. This hypothesis also mirrors the current leading theory for KS in which a widespread infection only induces the disease in susceptible children. We conclude that KS may be the acute febrile form of acrodynia. [Copyright &y& Elsevier]

Background: To investigate genotoxicity of the preservative thimerosal (Thi), and the cytoprotective and antioxidant effects of hyaluronic Acid (HA) and hydroxypropyl methylcellulose (HPMC) on Chang conjunctival cells. Method: Cells were divided into three groups. One group was exposed to Thi at various concentrations (0.00001 %∼0.001 %) for 30 min; the other two groups were pretreated with 0.3 % HA or 0.3 % HPMC for 30 min before the Thi exposure. After cell viability was evaluated, alkaline comet assay and detection of the phosphorylated form of the histone variant H2AX (γH2AX) foci were used to determine DNA damage. Reactive oxygen species (ROS) production was assessed by the fluorescent probe, 2', 7'-dichlorodihydrofluorescein diacetate (DCFH-DA). Results: A significant change of cell viability was observed after exposure to 0.001 % Thi for 30 min. DNA single- and double-strand breaks were significantly increased in a dose-dependent manner with Thi exposure. In addition, intracellular ROS induced by Thi was dose-dependent, except at 0.001 % less ROS was induced than at 0.0005 %. However, cells pretreated with 0.3 % HA or 0.3 % HPMC showed significantly increased cell survival, decreased DNA damage, and decreased ROS production compared to cells exposed to Thi alone. Pretreatment with 0.3 % HA was found to be even more protective than 0.3 % HPMC. Conclusion: Thi can induce DNA damage in human conjunctival epithelial cells, probably due to oxidative stress. HA and HPMC are protective agents that have antioxidant properties and can decrease DNA damage induced by Thi. Pretreatment of 0.3 % HA may be more protective of the ocular surface than 0.3 % HPMC. [ABSTRACT FROM AUTHOR]

Abstract: A fast, simple and green approach to direct determinate thimerosal in vaccines by photochemical vapor generation (PVG) coupled to optical emission spectrometry (OES) using dielectric barrier discharge (DBD) as excitation/emission source was described in this paper. With the exception of dilution and formic acid addition, the sample was not subjected to other treatment. This method eliminated the need for using strong oxidizing conditions and conventional chemical reducing agents. In addition, the DBD micro-plasma emission source was operated with low power (≤18W) and low gas consumption (120mLmin−1). A sample throughput of 30h−1 was obtained with the proposed flow injection-PVG-DBD-OES. The main operation parameters and the potential interferences affecting the determination were investigated. The detection limits for Hg2+ and thimerosal (as Hg) were calculated to be 0.19μgL−1 and 0.17μgL−1. Repeatability, expressed as the relative standard deviation of the spectral peak height, was 0.99% (n=11) and 1.9% (n=11) for 20μgL−1 Hg2+ and thimerosal standard, respectively. The proposed method was successfully applied to the analysis of commercial vaccines. All these results demonstrated that PVG-DBD-OES could provide a green way for the rapid detection of thimerosal in vaccines. [Copyright &y& Elsevier]

The present review summarizes data on neurological adverse events following vaccination in the relation to intensity, time of onset, taking into account the immunological and non-immunological mechanisms. The authors described the physio-logical development of the immune system and the possible immune system responses following vaccination. Toxic property of thimerosal - a mercury-containing preservative used in some vaccines was presented. The neurological compli-cations after vaccination were described. The role of vaccination in the natural course of infectious diseases and the current immunizations schedule in Poland was discussed. [ABSTRACT FROM AUTHOR]

Methylmercury (Met-Hg) and ethylmercury (Et-Hg) are powerful toxicants with a range of harmful neurological effects in humans and animals. While Met-Hg is a recognized trigger of oxidative stress and an endocrine disruptor impacting neurodevelopment, the developmental neurotoxicity of Et-Hg, a metabolite of thimerosal (TM), has not been explored. We hypothesized that TM exposure during the perinatal period impairs central nervous system development, and specifically the cerebellum, by the mechanism involving oxidative stress. To test this, spontaneously hypertensive rats (SHR) or Sprague-Dawley (SD) rat dams were exposed to TM (200 μg/kg body weight) during pregnancy (G10-G15) and lactation (P5-P10). Male and female neonates were evaluated for auditory and motor function; cerebella were analyzed for oxidative stress and thyroid metabolism. TM exposure resulted in a delayed startle response in SD neonates and decreased motor learning in SHR male (22.6%), in SD male (29.8%), and in SD female (55.0%) neonates. TM exposure also resulted in a significant increase in cerebellar levels of the oxidative stress marker 3-nitrotyrosine in SHR female (35.1%) and SD male (14.0%) neonates. The activity of cerebellar type 2 deiodinase, responsible for local intra-brain conversion of thyroxine to the active hormone, 3′,3,5-triiodothyronine (T3), was significantly decreased in TM-exposed SHR male (60.9%) pups. This coincided with an increased (47.0%) expression of a gene negatively regulated by T3, Odf4 suggesting local intracerebellar T3 deficiency. Our data thus demonstrate a negative neurodevelopmental impact of perinatal TM exposure which appears to be both strain- and sex-dependent. [ABSTRACT FROM AUTHOR]

Abstract: Monitoring T cells in combination with humoral response may be of value to predict clinical protection and cross-protective immunity after influenza vaccination. Elispot technique which measures cytokine produced after antigen-specific T cell stimulation is used routinely to detect and characterize anti-viral T cells. We found that the preservative thimerosal present in most H1N1 pandemic vaccines, induced in vitro abortive activation of T cells followed by cell death leading to false-positive results with the Elispot technique. The size of the spots, usually not measured in routine analysis, appears to be a discriminative criterion to detect this bias. Multi-dose vials of vaccine containing thimerosal remain important for vaccine delivery and our results alert about false-positive results of Elispot to monitor the clinical efficacy of these vaccines. We showed that this finding extends for other T cell monitoring techniques based on cytokine production such as ELISA. Although measuring in vitro immune response using the whole vaccine used for human immunization directly reflects in vivo global host response to the vaccine, the present study strongly supports the use of individual vaccine components for immune monitoring due to the presence of contaminants, such as thimerosal, leading to a bias in interpretation of the results. [Copyright &y& Elsevier]

That vaccines do not cause autism is now a widely accepted proposition, though a few dissenters remain. An 8-year court process in the US federal vaccine injury compensation court ended in 2010 with rulings that autism was not an adverse reaction to vaccination. There were two sets of trials: one against the measles–mumps–rubella (MMR) vaccine and one against the mercury-based preservative thimerosal. The MMR story is more widely known because of publicity surrounding the main proponent of an MMR–autism link, British doctor Andrew Wakefield, but the story of thimerosal in court is largely untold. This study examines the credibility battles and boundary work in the two cases, illuminating the sustaining world of alternative science that supported the parents, lawyers, researchers, and expert witnesses against vaccines. After the loss in court, the families and their advocates transformed their scientific arguments into an indictment of procedural injustice in the vaccine court. I argue that the very efforts designed to produce legitimacy in this type of lopsided dispute will be counter-mobilized as evidence of injustice, helping us understand why settling a scientific controversy in court does not necessarily mean changing anyone’s mind. [ABSTRACT FROM PUBLISHER]

Thimerosal, a mercury-containing vaccine preservative, is a suspected factor in the etiology of neurodevelopmental disorders. We previously showed that its administration to infant rats causes behavioral, neurochemical and neuropathological abnormalities similar to those present in autism. Here we examined, using microdialysis, the effect of thimerosal on extracellular levels of neuroactive amino acids in the rat prefrontal cortex (PFC). Thimerosal administration (4 injections, i.m., 240 μg Hg/kg on postnatal days 7, 9, 11, 15) induced lasting changes in amino acid overflow: an increase of glutamate and aspartate accompanied by a decrease of glycine and alanine; measured 10-14 weeks after the injections. Four injections of thimerosal at a dose of 12.5 μg Hg/kg did not alter glutamate and aspartate concentrations at microdialysis time (but based on thimerosal pharmacokinetics, could have been effective soon after its injection). Application of thimerosal to the PFC in perfusion fluid evoked a rapid increase of glutamate overflow. Coadministration of the neurosteroid, dehydroepiandrosterone sulfate (DHEAS; 80 mg/kg; i.p.) prevented the thimerosal effect on glutamate and aspartate; the steroid alone had no influence on these amino acids. Coapplication of DHEAS with thimerosal in perfusion fluid also blocked the acute action of thimerosal on glutamate. In contrast, DHEAS alone reduced overflow of glycine and alanine, somewhat potentiating the thimerosal effect on these amino acids. Since excessive accumulation of extracellular glutamate is linked with excitotoxicity, our data imply that neonatal exposure to thimerosal-containing vaccines might induce excitotoxic brain injuries, leading to neurodevelopmental disorders. DHEAS may partially protect against mercurials-induced neurotoxicity. [ABSTRACT FROM AUTHOR]

Thimerosal generates ethylmercury in aqueous solution and is widely used as preservative. We have investigated the toxicology of Thimerosal in normal human astrocytes, paying particular attention to mitochondrial function and the generation of specific oxidants. We find that ethylmercury not only inhibits mitochondrial respiration leading to a drop in the steady state membrane potential, but also concurrent with these phenomena increases the formation of superoxide, hydrogen peroxide, and Fenton/Haber-Weiss generated hydroxyl radical. These oxidants increase the levels of cellular aldehyde/ketones. Additionally, we find a five-fold increase in the levels of oxidant damaged mitochondrial DNA bases and increases in the levels of mtDNA nicks and blunt-ended breaks. Highly damaged mitochondria are characterized by having very low membrane potentials, increased superoxide/hydrogen peroxide production, and extensively damaged mtDNA and proteins. These mitochondria appear to have undergone a permeability transition, an observation supported by the five-fold increase in Caspase-3 activity observed after Thimerosal treatment. [ABSTRACT FROM AUTHOR]

Thimerosal, which is approximately 50% mercury by weight is a preservative widely used in vaccines since the 1930's. It meets the requirements for a preservative as set forth by Pharmacopeia challenge test and has been shown to be effective against a broad spectrum of pathogens. In July 1999, the Public Health Service agencies and vaccine manufacturers agreed that thimerosal should be reduced or eliminated in vaccines as a precautionary measure but, due to the lack of appropriate alternative, it is still extensively used in multiple dose formulations of vaccines such as hepatitis-B in developing countries. In this study the effect of the removal of thimerosal in two formulations of hepatitis B vaccines containing either aluminum hydroxide or aluminum phosphate were evaluated in Balb/c mice. These formulations were administered interperitoneally and the titer of antibody was determined by ELISA technique after 28 days. The geometric mean of antibody titer (GMT), seroconversion and seroprotection rates, ED50 and relative potency of different formulations were determined. The ED50 of thimerosal-free formulations were reduced by more than 35% in both preparations. In addition, GMT of antibody titer, seroconversion and seroprotection indicated significantly higher immunogenicity for thimerosal free formulations for both aluminum phosphate and hydroxide adjuvants. [ABSTRACT FROM AUTHOR]

Autism is a multisystem developmental disorder characterized by dysfunctional immunity and impaired brain function. Although autism is partly determined by genetic susceptibility factors, reported dramatic increases in the prevalence of autism in developed countries have intensified scientific focus on environmental exposures. Pre- and perinatal immunotoxic insults are now strongly suspected as contributors to this increase. Mercury (Hg) is both a neuro- and an immunotoxin and continues to be used in some pediatric vaccines in the form of the preservative thimerosal. Although currently there are no direct human studies on the risks of Hg exposure from thimerosal-containing vaccines (TCVs), animal studies show that doses relevant to human TCV exposure can result in adverse neurodevelopmental outcomes. To date, TCVs continue to be administered on a regular basis to potentially the most vulnerable populations: pregnant women and children. In light of existing experimental evidence, the rationale for using this known immunotoxic and neurotoxic substance in human vaccines should be reconsidered. [ABSTRACT FROM AUTHOR]

Abstract: Background: In 1999, the American Academy of Pediatrics (AAP) and the U.S. Public Health Service (USPHS) issued a joint statement on thimerosal in vaccines, which advised clinicians to temporarily postpone the first dose of hepatitis B vaccine for infants born to hepatitis B surface antigen (HBsAg)-negative women. In 2005, the Advisory Committee on Immunization Practices (ACIP) updated the strategy to improve prevention of perinatal and early childhood hepatitis B virus (HBV) transmission. Objectives: To evaluate the progress in hepatitis B birth dose vaccination coverage in birth year cohort from 1998 to 2007 and assess the impact of changes in ACIP recommendations on the birth dose coverage. Methods: Birth year cohort study of hepatitis B birth dose vaccination status of 200,865 children aged 19–35 months in the United States and by selected socio-demographic factors; percentage increases of hepatitis B birth dose vaccination coverage between two consecutive birth year cohorts from 1998 to 2007. Results: From 1998 to 1999, hepatitis B birth dose vaccination coverage declined overall in the United States and among selected socio-demographic groups (P <0.001). Conversely, from 1999 to 2007 hepatitis B birth dose vaccination coverage increased significantly by birth year cohort (P <0.001), from approximately 30% in the 1999 birth year cohort to approximately 60% in the 2007 birth year cohort. The first significant increase in hepatitis B birth dose vaccination coverage occurred from 2000 to 2001 birth year cohort. Coverage increases ranged from 8.4% to 11.9% (P <0.001) in the U.S. and across all socio-demographic strata. The second largest increase in hepatitis B birth dose vaccination coverage occurred from 2005 to 2006 birth year cohort in the U.S. and among almost all socio-demographic strata, ranging from 5.6% to 8.7% (P <0.001). Forty-one of the 50 states and the District of Columbia (80%) in the U.S. had increases in hepatitis B birth dose vaccination coverage from 2005 to 2006 birth year cohort. Conclusions: The United States has made substantial progress in increasing hepatitis B birth dose vaccination and recovered from coverage declines associated with temporary postponement of the birth dose in 1999. The hepatitis B birth dose coverage in the U.S. remains substantially below the Healthy People 2020 target of 85%. [Copyright &y& Elsevier]

Abstract: Even though neuronal toxicity due to organomercury compounds is well known, thimerosal, an organomercury compound, is widely used in pediatric vaccine preservation. In the present study, we examined whether embryonic exposure to thimerosal affects early development of serotonergic neurons. Thimerosal (1mg Hg/kg) was intramuscularly administered to pregnant rats on gestational day 9 (susceptible time window for development of fetal serotonergic system), and fetal serotonergic neurons were assessed at embryonic day 15 using anti-serotonin antibodies. A dramatic increase in the number of serotonergic neurons localized to the lateral portion of the caudal raphe was observed in thimerosal group (1.9-fold increase, p <0.01 compared to control). These results indicate that embryonic exposure to thimerosal affects early development of serotonergic neurons. [Copyright &y& Elsevier]

Abstract: The neurotoxic organomercurial thimerosal (THIM), used for decades as vaccine preservative, is a suspected factor in the pathogenesis of some neurodevelopmental disorders. Previously we showed that neonatal administration of THIM at doses equivalent to those used in infant vaccines or higher, causes lasting alterations in the brain opioid system in rats. Here we investigated neonatal treatment with THIM (at doses 12, 240, 1440 and 3000μgHg/kg) on behaviors, which are characteristically altered in autism, such as locomotor activity, anxiety, social interactions, spatial learning, and on the brain dopaminergic system in Wistar rats of both sexes. Adult male and female rats, which were exposed to the entire range of THIM doses during the early postnatal life, manifested impairments of locomotor activity and increased anxiety/neophobia in the open field test. In animals of both sexes treated with the highest THIM dose, the frequency of prosocial interactions was reduced, while the frequency of asocial/antisocial interactions was increased in males, but decreased in females. Neonatal THIM treatment did not significantly affect spatial learning and memory. THIM-exposed rats also manifested reduced haloperidol-induced catalepsy, accompanied by a marked decline in the density of striatal D2 receptors, measured by immunohistochemical staining, suggesting alterations to the brain dopaminergic system. Males were more sensitive than females to some neurodisruptive/neurotoxic actions of THIM. These data document that early postnatal THIM administration causes lasting neurobehavioral impairments and neurochemical alterations in the brain, dependent on dose and sex. If similar changes occur in THIM/mercurial-exposed children, they could contribute do neurodevelopmental disorders. [Copyright &y& Elsevier]