Administration methods and dosage of poly(lactic acid)-glycol intervention to myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalitis mice

BACKGROUND

Myelin oligodendrocyte glycoprotein-associated disorders (MOGAD) is an autoimmune central nervous system disease. Antigen-specific immune tolerance using nanoparticles such as Polylactic-co-glycolic acid (PLGA) have recently been used as a new therapeutic tolerization approach for CNS autoimmune diseases. We examined whether MOG1-125 conjugated with PLGA could induce MOG-specific immune tolerance in an experimental autoimmune encephalitis (EAE) mouse model. EAE was induced in sixty C57BL/6 J wild-type mice using MOG1-125 peptide with complete Freund's Adjuvant. The mice were divided into 12 groups (n = 5 each) to test the ability of MOG1-125 conjugated PLGA intervention to mitigate the severity or improve the outcomes from EAE with and without rapamycin compared to antigen alone or PLGA alone. EAE score and serum MOG-IgG titers were compared among the interventions.Kindly check and confirm the processed Affiliation “4” is appropriate.I confirmed the Aff 4.Affiliation: Corresponding author information have been changed to present affiliation. Kindly check and confirm.I checked and confirmed the Corresponding author's information.

RESULTS

Mice with EAE that were injected intraperitoneally with MOG1-125 conjugated PLGA + rapamycin complex showed dose-dependent mitigation of EAE score. Intraperitoneal and intravenous administration resulted in similar clinical outcomes, whereas 80% of mice treated with subcutaneous injection had a recurrence of clinical score worsening after approximately 1 week. Although there was no significant difference in EAE scores between unconjugated-PLGA and MOG-conjugated PLGA, serum MOG-IgG tended to decrease in the MOG-conjugated PLGA group compared to controls.

CONCLUSION

Intraperitoneal administration of PLGA resulted in dose-dependent and longer-lasting immune tolerance than subcutaneous administration. The induction of immune tolerance using PLGA may represent a future therapeutic option for patients with MOGAD.

PLGA nanoparticles engineering extracellular vesicles from human umbilical cord mesenchymal stem cells ameliorates polyethylene particles induced periprosthetic osteolysis

The wear particle-induced dissolution of bone around implants is a significant pathological factor in aseptic loosening, and controlling prosthetic aseptic loosening holds crucial social significance. While human umbilical cord mesenchymal stem cell-derived exosomes (HucMSCs-Exos, Exos) have been found to effectively promote osteogenesis and angiogenesis, their role in periprosthetic osteolysis remains unexplored. To enhance their in vivo application, we engineered HucMSCs-Exos-encapsulated poly lactic-co-glycolic acid (PLGA) nanoparticles (PLGA-Exos). In our study, we demonstrate that PLGA-Exos stimulate osteogenic differentiation while inhibiting the generation of reactive oxygen species (ROS) and subsequent osteoclast differentiation in vitro. In vivo imaging revealed that PLGA-Exos released exosomes slowly and maintained a therapeutic concentration. Our in vivo experiments demonstrated that PLGA-Exos effectively suppressed osteolysis induced by polyethylene particles. These findings suggest that PLGA-Exos hold potential as a therapeutic approach for the prevention and treatment of periprosthetic osteolysis. Furthermore, they provide novel insights for the clinical management of osteolysis.

Hyperosmolar metabolic acidosis in burn patients exposed to glycol based topical antimicrobials-A systematic review

BACKGROUND

The well documented susceptibility of burn patients to acquired infections via damaged skin mandates application of antimicrobial agents. These agents are dissolved in various vehicles that augment skin absorption thus allowing greater efficacy. Polyethylene glycol (PEG) and Propylene glycol (PropG) are among the most commonly used vehicles, and both have been used in numerous medications and cosmetic products over the past few decades. Rarely, burn patients treated with agents containing these glycols present with a life threatening systemic toxidrome of hyperosmolar metabolic acidosis. We present a systematic review of outcomes in burn patients treated with similar agents.

METHODS

Relevant studies were identified through systematic searches conducted in MEDLINE (Ovid), Embase (Ovid), CENTRAL (Ovid), and Web of Science (Thomson Reuters), from database inception to August 4th, 2016. All publications of clinical burn patient studies included at least one arm receiving a glycol based topical therapy.

RESULTS

A total of 61 studies involving 10,282 patients and 4 different antimicrobial medications fulfilled the inclusion criteria. Nine burn patients (0.09%) were documented to present with hyperosmolar metabolic acidosis during topical silver sulfadiazine treatment. Propylene glycol isolated from their blood accounted for the high osmole gap.

CONCLUSION

This first systematic review found very few cases of documented hyperosmolar metabolic acidosis, all within one study that had set to specifically explore this toxidrome. High index of suspicion with frequent osmolar gap monitoring may help identify future toxicities in a timely manner.

Volatile organic compounds enhance allergic airway inflammation in an experimental mouse model

BACKGROUND

Epidemiological studies suggest an association between exposure to volatile organic compounds (VOCs) and adverse allergic and respiratory symptoms. However, whether VOCs exhibit a causal role as adjuvants in asthma development remains unclear.

METHODS

To investigate the effect of VOC exposure on the development of allergic airway inflammation Balb/c mice were exposed to VOCs emitted by new polyvinylchloride (PVC) flooring, sensitized with ovalbumin (OVA) and characterized in acute and chronic murine asthma models. Furthermore, prevalent evaporated VOCs were analyzed and mice were exposed to selected single VOCs.

RESULTS

Exposure of mice to PVC flooring increased eosinophilic lung inflammation and OVA-specific IgE serum levels compared to un-exposed control mice. The increased inflammation was associated with elevated levels of Th2-cytokines. Long-term exposure to PVC flooring exacerbated chronic airway inflammation. VOCs with the highest concentrations emitted by new PVC flooring were N-methyl-2-pyrrolidone (NMP) and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TXIB). Exposure to NMP or TXIB also increased the allergic immune response in OVA-sensitized mice. In vitro or in vivo exposure to NMP or TXIB reduced IL-12 production in maturing dendritic cells (DCs) and enhanced airway inflammation after adoptive DC transfer into Balb/c mice. At higher concentrations both VOCs induced oxidative stress demonstrated by increased isoprostane and glutathione-S-transferase-pi1 protein levels in the lung of non-sensitized mice. Treatment of PVC flooring-exposed mice with N-acetylcysteine prevented the VOC-induced increase of airway inflammation.

CONCLUSIONS

Our results demonstrate that exposure to VOCs may increase the allergic immune response by interfering with DC function and by inducing oxidative stress and has therefore to be considerate as risk factor for the development of allergic diseases.

Emergent and unusual allergens in cosmetics

Allergic contact dermatitis from cosmetics is a common problem that is occasionally caused by new or rare allergens. When a patient has a positive patch test to a cosmetic product but to none of the common or commercially available allergens, it is important to further patch-test this patient to the ingredients of the product. Thorough testing with the breakdown of ingredients, usually obtained through cooperation with the manufacturer, often allows identification of the culprit allergen in the cosmetic product. In this article, we discuss emerging or rare allergens discovered by this method, including nail lacquer and lipstick allergens, copolymers, shellac, alkyl glucosides, glycols, protein derivatives, idebenone, and octocrylene.

[Assessment of the biological age of workers engaged in the production of glycol-based organic mixtures]

The paper presents the results of assessment of the biological age of workers who are in contact with organic compounds. Analysis of the findings has indicated that there is a relationship between the level of free radical oxidation and the cytotoxic properties of substances. The damaging effect of chemical agents on the workers appeared as higher parameters of biological age.

Membranous nephropathy, hydrocarbon exposure and genetic variants of hydrocarbon detoxification

Modulation of biotransformation by genetic traits may be important in determining environmentally-induced nephrotoxicity. We conducted a case-control study to investigate the role of occupational hydrocarbon exposure, along with polymorphisms of the genes coding for N-acetyltransferase 2 (NAT2) and glutathione S-transferase mu (GSTmu), in the development of idiopathic membranous glomerulonephritis (IMGN). Patients (n=36) with biopsy-proven IMGN were matched with healthy controls for age, gender, and geographical area. Lifetime hydrocarbon exposure was assessed by a validated questionnaire. The polymorphisms of the NAT2 and GSTmu genes (GSTM1) were defined by use of a polymerase chain reaction on white-cell DNA from peripheral blood. Exposure to hydrocarbons was significantly greater in patients with IMGN than in controls (mean+/-SEM hydrocarbon exposure score 11 003+/-2955.7 vs. 4352+/-1418, p<0.02). NAT2 acetylator status was identical in patients and controls with 23 (63.9%) fast and 13 (36.1%) slow acetylators in each group. GSTmu was present in 15 (41.7%) patients and 16 (44.4%) controls. While occupational exposure to hydrocarbons remains a likely factor in its pathogenesis, further work is required to identify the genetic polymorphisms that modulate the risk of IMGN.

[Adverse effects of glycolic irrigation solutions]

The aim of this study was to evaluate the frequency and the gravity of Trans Urethral Resection of the Prostate Syndrome or 'TURP Syndrome,' which occurs when irrigating fluids containing 1.5 per cent glycocolle are used. All the adverse effects that occurred with 5 products containing 1.5 per cent glycocolle which were notified to the pharmacovigilance structures in France were reviewed. The adverse effects notified comprised 24 cases of TURP Syndrome and 5 of renal failure. TURP Syndrome consisted of neurological signs (92 per cent); cardiovascular signs (54 per cent); visual disturbance (42 per cent) and digestive signs (25 per cent). Hyponatraemia occurred in all patients (mean 113 +/- 6 mmol.l-1) and 25 per cent of patients died. In 27 per cent of cases TURP Syndrome occurred when glycocolle was in contravention of AMM guidelines. The Drugs Agency has requested that modification be included in the Vidal pharmacopoeia (warnings and adverse reactions) and on glycocolle bags and that surgeons and anaesthetists be informed.

Congenital malformation and maternal occupational exposure to glycol ethers. Occupational Exposure and Congenital Malformations Working Group

Glycol ethers are found in a wide range of domestic and industrial products, many of which are used in women's work environments. Motivated by concern about their potential reproductive toxicity, we have evaluated the risk of congenital malformations related to glycol ether exposure during pregnancy as part of a multicenter case-control study, conducted in six regions in Europe. The study comprised 984 cases of major congenital malformations and 1,134 controls matched for place and date of birth. Interviews of the mothers provided information about occupation during pregnancy, sociodemographic variables, and other potential risk factors (medical history, tobacco, alcohol, drugs). A chemist specializing in glycol ethers evaluated exposure during pregnancy, using the job description given by the mother, without knowledge of case or control status. We classified malformations into 22 subgroups. The overall odds ratio (OR) of congenital malformation associated with glycol ether exposure was 1.44 [95% confidence interval (CI) = 1.10-1.90], after adjustment for several potential confounders. The association with exposure to glycol ethers appeared particularly strong in three subgroups: neural tube defects (OR = 1.94; 95% CI = 1.16-3.24), multiple anomalies (OR = 2.00; 95% CI = 1.24-3.23), and cleft lip (OR = 2.03; 95% CI = 1.11-3.73). In this last subgroup, risk, especially of an isolated defect, tended to increase with level of exposure.

Biomonitoring of technical grade 1-alkoxy-2-propanol acetates by analysing urinary 2-alkoxypropionic acids

Today commercially available 1-alkoxy-2-propanol acetates contain a harmful isomer 2-alkoxy-1-propanol acetates, which makes up less than 20% of the commercial product. This harmful isomer provides a means with which to study the toxicity and exposure to alkoxypropanols. Assessing exposure to technical grade 1-alkoxy-2-propanol acetates through the biological monitoring of urinary 2-alkoxypropionic acids has been found to be the most accurate method. The method developed in this study provides a procedure for the simultaneous urinalysis of methoxyacetic acid (MAA), ethoxyacetic acid (EAA), butoxyacetic acid (BAA), oxalic acid (OA), 2-methoxypropionic acid (2-MPA) and 2-ethoxypropionic acid (2-EPA). This possibility is very valuable in workplaces where workers are exposed simultaneously to different glycol ethers. This study was conducted among 54 silkscreen printers, who gave a urine sample to be analysed using a capillary gas chromatograph for 2-MPA and 2-EPA. The mean urinary concentrations of 2-MPA and 2-EPA were 1.27 (S.D. = 1.60) nmol/mol creatinine (median = 0.53, n = 26) and 1.23 (S.D. = 2.31) mmol/mol creatinine (median = 0.26, n = 39), respectively. The urinary excretion of 2-MPA and 2-EPA immediately after shift was linearly dependent on the preceding technical grade 1-methoxy-2-proponol acetate (7 = 0.16x + 0.26, n = 26 R2 = 0.78) and technical grade 1-ethoxy-2-propanol acetate (y = 2.05x - 0.09, n = 39, R2 = 0.68) respective exposure, as measured in the workers' breathing zone. According to the results of this study it is possible to monitor exposure to the technical grade 1-methoxy-2-propanol acetate and technical grade 1-ethoxy-2-propanol acetate through urinalysis of 2-MPA and 2-EPA.

[Evaluation of risks of glycol ethers for the reproductive health]

Glycol ethers (Ge) are a family of substances with a growing use in industrial and domestic products for the two last decades. Ge (group 1 and 2) are experimentally toxic for reproduction and development, at various levels. That begins to be found in humans. Epidemiological studies confirm toxicokinetic data showing humans are more sensitive than animals, because of a low excretion rate of the toxic metabolites. Occupational and consumer exposures are frequently higher than reference concentrations deducted from animal data. They may be involved in the growing number of genital reproductive system and reproduction anomaly, observed in most developed countries. Genetic toxicity is suspected from experimental data, but further investigations are needed.

Skin reactions to hexylene glycol

Hexylene glycol (HG), which has been used for years in industrial chemicals and cosmetics, has recently been introduced in topical corticosteroids. We studied the irritant and sensitizing properties of HG in eczema patients. HG at 50% or 30% and propylene glycol (PG) at 30% in water were patch tested in 823 eczema patients subjected to routine patch testing. Oedema and erythema reactions from HG occurred in 2.8% of the patients. The corresponding result for PG was 3.8%. 50% HG equalled 30% PG in producing a visible reaction. In patch tests with dilution series, 2 patients reacted to 1% HG, but in both cases ROAT with HG remained negative. One other patient with a 3+ patch test reaction to both 30% PG and 50% HG had a positive ROAT result to 30% HG in water and to 5% PG in a cream base. PG, but not HG, increased transepidermal water loss both in atopic normal-looking skin and among healthy controls. The present results suggest that HG is less irritating that PG under occlusion, but that delayed contact allergic reactions may occur.

[Cardiocirculatory findings in a group of workers exposed to nitro derivatives. A pathogenetic hypothesis of withdrawal hazard]

After briefly recalling the professional pathology characteristics of workers exposed to nitro derivatives and the perplexities surrounding the actual pathogenetic mechanism of the "Withdrawal hazard", the AA report the results of an investigation carried out among the workers of a dynamite producing plant. In the study, the NG and EGDN environmental levels were checked and the workers were submitted to ECG tracings, ECG D according to Holter, and monitoring of postural pressure changes both during exposure to the substances and during time-outs. The results obtained showed that the concentrations found in the plant were practically within the recommended TLV values, with no pathological modifications of the parameters examined. The AA put forward a pathogenetic hypothesis based on these findings and analyzing epidemiologic data on coronary sudden death as well as the mechanisms regarded as responsible for the disorders described in the literature in professionally exposed subjects. According to such hypothesis, the "Withdrawal hazard" (if any) would not be due to the cessation of the vasodilation effect of the nitro derivatives but would be a "rebound" phenomenon following the NG - and EGDN - inhalation induced stimulation to the production of endothelial prostaglandins, and of EDRF in particular, in exposed workers. The withdrawal of nitro derivatives inhalation would thus eliminate a vascular and coronary protection mechanism in the case of pathogenetic noxae at cardiovascular level. Such an interpretation would at last account for the time elapsing between cessation of work and occurrence of the disorders, which would not be justified by the cessation of the mere vasodilating action, since this wears out within a few hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone marrow injury in lithographers exposed to glycol ethers and organic solvents used in multicolor offset and ultraviolet curing printng processes

Prompted by referral of a printer with aplastic anemia, a study of possible marrow toxicity of workplace substances was undertaken. Dermal and respiratory exposures to dipropylene glycol monomethyl ether, ethylene glycol monoethyl ether, and a range of aliphatic, aromatic and halogenated hydrocarbons used for offset and ultraviolet cured multicolor printing were documented. Evaluation of seven co-workers revealed normal peripheral blood pictures, but bone marrow specimens demonstrated clear patterns of injury in three while the others had nonspecific signs of marrow effect. These changes could not be explained by known risk factors. The authors conclude that further evaluation of possible bone marrow toxicity resulting from exposure to glycol ethers and ultraviolet curing printing processes is warranted. More generally, we have provided data demonstrating that peripheral blood counts may be an insensitive tool for the study of hematologic toxins acting at the bone marrow level.

Delayed irritation: hexanediol diacrylate and butanediol diacrylate

Ephemeral topical contact with hexanediol diacrylate and butanediol diacrylate may cause delayed irritant dermatitis. During 4 years' observation of 20 workers utilizing these substances in the electron beam coating department of a door factory, contact sensitization did not occur. The characteristics of delayed contact irritancy are enumerated. The disease must be distinguished from allergic contact dermatitis, acute irritant dermatitis and cumulative irritant dermatitis.

Block copolyurethanes in the urinary system

Free floating segments of block copolyurethane were implanted into rat bladders and compared with similar implants of silicone rubber. This urethane was far superior to silicone rubber in its ability to withstand incrustation in the rat bladder. Ten dogs had a segment of right ureter replaced by a tubular segment of smooth (or film) urethane and were followed with intravenous urography. At 1 month, eight of 10 dogs had right hydronephrosis. At the time of sacrifice (4 or 8 months) seven dogs had reduced hydronephrosis, and in three dogs intravenous urography was unsatisfactory for grading. Only two of the ten dogs had significant urinary infection. A smooth protein-like coasting appeared along the lumen of the graft, incrustation was minimal, and new mucosa and smooth muscle regeneration was seen. This material was well tolerated in the urinary tracts of dogs and rats.

Irritant dermatitis from diallylglycol carbonate monomer in the optical industry: clinical and experimental studies of cutaneous tolerance and chemical investigations

The diallylglycol carbonate monomer causes dermatitis due to irritation in the optical industry. Cutaneous intolerance may effect as many as 70% of the exposed persons employed. Almost all control subjects who where patch-tested showed irritation at a 2% concentration. The histological effects were an acute oedema with inflammation of the papillary dermis, and diapedesis of neutrophil polymorphonuclear leukocytes. Experiments on animals confirmed the irritant nature of the product; in the rabbit, a single application produced irritation, but to a lesser degree than in humans. Tests for possible sensitizing effects in the guinea pig have given negative results. Chemical analysis of the monomer revealed the presence of diallyl carbonate and acrolein. Allyl alcohol was detected in only one case. Patch tests were carried out in a group of control subjects with acrolein, diallyl carbonate and allyl alcohol. The histological appearance of the lesions caused by acrolein was quite different from that due to diallyglycol carbonate. It is probable that the irritant is the diallylglycol carbonate monomer itself.