Clinical characteristics of an allergic reaction to a polyether dental impression material.

Allergic and hypersensitivity reactions to dental impression materials may occur throughout dental treatment, with diverse manifestations from slight redness to severe pain and a burning mouth with total stomatitis. Patients are often unaware of these allergic reactions, which makes early identification of the cause almost impossible. In addition, symptoms usually begin after 24 hours and mostly in patients with a preexisting history of allergic responses. This report describes a patient with a suspected allergic reaction to a polyether dental impression material during prosthetic rehabilitation associated with a mandibular telescopic denture. Although instances of such occurrence are rare, clinicians need to be aware of these symptoms and select materials carefully for patients with a history of allergy.

Multicenter Patch Testing With a Resol Resin Based on Phenol and Formaldehyde Within the International Contact Dermatitis Research Group.

BACKGROUND: Contact allergy to phenol-formaldehyde resins (PFRs) based on phenol and formaldehyde is not detected by a p-tertiary-butylphenol-formaldehyde resin included in most baseline patch test series. OBJECTIVE: The aims of this study were to investigate the contact allergy rate to PFR-2 in an international population and to investigate associated simultaneous allergic reactions. METHODS: Thirteen centers representing the International Contact Dermatitis Research Group included PFR-2 into their patch test baseline series during a period of 6 months in 2012. RESULTS: Of 2259 patients tested, 28 (1.2%) reacted to PFR-2. Of those 28 individuals, one had a positive reaction to formaldehyde and 2 to p-tertiary-butylphenol-formaldehyde resin. Simultaneous allergic reactions were noted to colophonium in 3, to Myroxylon pereirae in 5, and to fragrance mix I in 8. CONCLUSIONS: The contact allergy frequency in the tested population (1.2%) merits its inclusion into the international baseline series and possibly also into other baseline series after appropriate investigations. Significantly, overrepresented simultaneous allergic reactions were noted for M. pereirae and fragrance mix I.

Is p-tert-butylphenol-formaldehyde resin (PTBP-FR) in TRUE Test® (Mekos test) sensitizing the tested patients?

BACKGROUND: In a population study using TRUE Test®, we noted late reactions to p-tert-butylphenol-formaldehyde resin (PTBP-FR) in 0.5% of subjects tested. OBJECTIVES: In order to explore possible test sensitization, differences in the contents of sensitizers within PTBP-FR in test preparations for TRUE Test® and Finn Chambers® were analysed. Subjects allergic to PTBP-FR and subjects with late reactions to PTBP-FR were retested in order to explore whether these groups reacted to different PTBP-FR sensitizers. PATIENTS/MATERIALS/METHODS: Four individuals with late reactions and 5 subjects with established allergy to PTBP-FR were retested with defined PTBP-FR sensitizers. PTBP-FR constituents in patches from TRUE Test® were analysed with high-performance liquid chromatography. Previously analysed samples of PTBP-FR constituents served as a reference. RESULTS: The pattern of reaction to PTBP-FR sensitizers was similar in both groups. Subjects with suspected sensitization had somewhat stronger reactions than controls. The concentrations of monomers, dimers and trimers were generally higher in the TRUE Test® resin than in reference substances. CONCLUSIONS: Retesting did not add information regarding causes of possible sensitization. Analysis showed that the resin used in TRUE Test® has a lower degree of polymerization or condensation, which may enhance its sensitizing properties. A follow-up of late reactions to PTBP-FR in TRUE Test® should be carried out.

DuraSeal as a spacer to reduce rectal doses in low-dose rate brachytherapy for prostate cancer.

The purpose of this study was to evaluate the utility of off-label use of DuraSeal polyethylene glycol (PEG) gel in low-dose rate (LDR) prostate brachytherapy seed implantation to reduce rectal doses. Diluted DuraSeal was easy to use and, in spite of a clearance effect, useful in decreasing D2cc rectal doses.

Pilot study of angiogenic response to yttrium-90 radioembolization with resin microspheres.

PURPOSE: To investigate the impact of radioembolization with yttrium-90 resin microspheres on the regulation of angiogenesis through observation of serial changes in a spectrum of angiogenic markers and other cytokines after therapy. MATERIALS AND METHODS: This prospective pilot study enrolled 22 patients with liver-dominant disease deriving from biopsy-proven hepatocellular carcinoma (HCC) (n = 7) or metastatic colorectal carcinoma (mCRC) (n = 15). Circulating angiogenic markers were measured from serum samples drawn at baseline and at time points after therapy ranging from 6 hours to 120 days. Using multiplex enzyme-linked immunosorbent assay, several classic angiogenesis factors (vascular endothelial growth factor [VEGF], angiopoietin-2 [Ang-2], basic fibroblast growth factor [bFGF], platelet-derived growth factor subunit BB [PDGF-BB], thrombospondin-1 [Tsp-1]) and nonclassic factors (follistatin, leptin, interleukin [IL]-8) were evaluated. RESULTS: Increases in cytokine levels ≥ 50% over baseline were observed in more than half of all patients studied for many cytokines, including classic angiogenic factors such as VEGF, Ang-2, and Tsp-1 as well as nonclassic factors IL-8 and follistatin (range, 36%-82% for all cytokines). Baseline cytokine levels in patients with overall survival (OS) < 6 months differed significantly from patients with longer survival for Ang-2 (P = .033) and IL-8 (P = .041). Patients with OS ≤ 6 months exhibited transient increases in VEGF and PDGF-BB after therapy compared with patients with OS > 6 months. CONCLUSIONS: Radioembolization is associated with early transient increases in many angiogenic cytokines. In this small sample size, some of these changes were associated with worse OS. This research has important implications for future studies of radioembolization with antiangiogenic therapy performed during and after the procedure.

Outcome of children with melamine-induced urolithiasis: results of a two-year follow-up.

OBJECTIVE: Our purpose is to describe the characteristics and the outcome of melamine-induced renal and urinary tract injury in young children who consumed melamine-contaminated infant formula. METHODS: This is a descriptive longitudinal study over 2 years in 240 children with melamine-induced urolithiasis screened in our hospital from September 15 to October 31, 2008. Ultrasonography and serum creatinine (SCr), urea, ß2-microglobulin (MG), cystatin C (Cys C), urinary Cr (UCr), microalbumin (mALB), α1-MG, ß2-MG, n-acetyl-ß-d-glucosaminidase (NAG) and retinol-binding protein (RBP) measurements were performed. RESULTS: The children ranged in age from 1 to 82 months, and 145 were males. The largest calculus was 33 mm in diameter. X-ray diffraction pattern of the calculi displayed two diffraction peaks at 10.9° and 27.7° (2θ). Surgical management was performed in 14 patients. In 226 patients without surgical management, the calculi were passed in 59.63% patients within 1 month, in 85.40% within 6 and in 91.15% within 24 months. Increased SCr and urea levels were noted in three and six patients, respectively, at the time of diagnosis. The SCr, serum ß2-MG, and Cys C levels at the time of diagnosis were higher than those at 3 and 6 months after diagnosis (P < 0.05, respectively). The levels of mALB/UCr, NAG/UCr, and RBP/UCr at the time of diagnosis were higher than those at 3, 6, 12, and 24 months after diagnosis (P < 0.05, respectively). α1-MG/UCr and ß2-MG/UCr levels at the time of diagnosis were similar to those at 3 months after diagnosis, and significantly higher than those in the follow-up period (P < 0.05, respectively). CONCLUSION: Melamine might injure both the renal glomerulus and the tubule, and that the predominant lesion is urolithiasis. The compositions of melamine-induced urolithiasis are melamine and cyanuric acid crystals. The urolithiasis might persist for over 2 years and cause irreversible damage. Therefore, a long-term follow-up for all patients is required.

Obliterative bronchiolitis in fibreglass workers: a new occupational disease?

RATIONALE AND OBJECTIVES: Obliterative bronchiolitis (OB) is a rare disease with a small number of established occupational aetiologies. We describe a case series of severe OB in workers making glass-reinforced plastics. METHODS: Workplace exposures were the likely cause after the independent diagnosis of OB in two workers laying up the fibreglass hulls of yachts; the second worker took over the job of the first after he left following a lung transplant. Presentation of these two cases at international meetings led to others identifying similar workers. MAIN RESULTS: We identified six workers with good evidence of OB. All were involved in preparing fibreglass with styrene resins, five as boat builders laying up fibreglass hulls and one during cooling-tower fabrication. The disease came on rapidly without unusual acute exposures. Two patients had lung transplants, while another died while waiting for one. Histology confirmed OB in the four with biopsies/post-mortem examinations or explanted lungs. CONCLUSIONS: A rare, potentially fatal disease occurring in six workers laying up fibreglass with styrene resins from five different worksites suggests that work exposures were the cause of their OB. The precise agent responsible awaits identification.

p-tert-Butylphenol formaldehyde resin and its impact on children.

: p-tert-Butylphenol formaldehyde resin (PTBPFR) is widely used as an adhesive owing to its rapid onset of action, durability, flexibility, and heat resistance. Moreover, because of its tackiness, it is particularly useful as a glue component on both leather and rubber products. Sensitization to this resin has been increasing since the first cases of PTBPFR contact allergy in the late 1950s, and pediatric contact allergy to this resin is a significant problem. p-tert-Butylphenol formaldehyde resin has been reported as a leading cause of shoe-associated dermatitis internationally, as well as a cause of allergic contact dermatitis from its use in neoprene wet suits and sports equipment such as shin guards. In summary, patch test screening of both adults and children with PTBPFR is important, given the ubiquitous use of this chemical.

Bra-associated allergic contact dermatitis: p-tert-butylphenol formaldehyde resin as the culprit.

P-tert-butylphenol formaldehyde resin (PTBPFR) is recognized as a significant source of allergic contact dermatitis in adults and children in association with athletic gear, shoes, and neoprene. To our knowledge, this is the first case report of allergic contact dermatitis with PTBPFR associated with padded foam bras.

Effects of the iron-chelating agent deferoxamine on triethylene glycol dimethacrylate, 2-hydroxylethyl methacrylate, hydrogen peroxide-induced cytotoxicity.

Triethylene glycol dimethacrylate (TEGDMA) and 2-hydroxylethyl methacrylate (HEMA) are known to deplete glutathione in mammalian cells, generate reactive oxygen species (ROS), and cause oxidative stress. In this study, we investigated whether hydroxyl radicals (·OH), the most lethal and genotoxic ROS, and the Fenton reaction are involved in the cytotoxicity of resin monomers to four different cell types, namely MC3T3-E1 preosteoblasts, human dental pulp cells (HDPCs), human gingival fibroblasts, and L929 mouse fibroblasts. Deferoxamine (DFO), an iron chelating agent, effectively protected MC3T3-E1 cells from resin monomer-induced cytotoxicity, indicating that cytotoxicity was caused primarily by hydroxyl radicals. However, DFO only had a protective effect against relatively high concentrations of TEGDMA and HEMA in HDPCs and human gingival fibroblasts, and resin monomer-induced cytotoxicity in L929 was not attenuated by DFO. A labile iron pool (LIP) was detectable only in MC3T3-E1 cells among the four cell types. This indicates that the generation of hydroxyl radicals induced by resin monomers is likely dependent on LIP levels. In contrast to resin monomers, hydrogen peroxide (H(2)O(2))-induced cytotoxicity was not prevented by DFO in any of the cell types examined, although hydroxyl radicals were detected in MC3T3-E1 cells and HDPCs on exposure to exogenous H(2)O(2). This result suggests that generation of hydroxyl radicals is not always the primary cause of cytotoxicity in H(2)O(2)-treated cells.

DuraSeal-hematoma: concealed hematoma causing spinal cord compression.

STUDY DESIGN: Case description. OBJECTIVE: To present a case report which highlights a complication following the use of Duraseal in posterior cervical surgery. SUMMARY OF BACKGROUND DATA: Duraseal is increasingly used to repair cranial and spinal dural defects to prevent cerebrospinal fluid leakage. Although it is well established that the hydrogel expands after implantation and may result in compressive effects, the phenomenon of Duraseal-entrapped hematoma has not previously been reported. METHODS: The authors report a 80-year-old woman who presented with cervical myelopathy secondary to canal stenosis. The patient underwent decompressive cervical laminectomies. The surgery was complicated by an unintended durotomy. A thin layer of Duraseal was applied over the dural surface and a suction drain placed before wound closure. The patient awoke from surgery without any new neurologic deficits but experienced delayed functional deterioration. Urgent magnetic resonance imaging demonstrated an extradural hematoma with severe cord compression. RESULTS: The patient underwent urgent surgery. Intraoperatively, the Duraseal was found to have formed a restrictive layer, completely entrapping the extradural hematoma with resultant spinal cord compression. Minimal blood clot was found external to the hydrogel layer. CONCLUSION: Although Duraseal can provide an effective and water-tight dural repair, it also has the potential to "entrap" extradural bleeding which otherwise may have been evacuated by a wound drain placed under suction. Our experience has shown that Duraseal should be used judiciously with recognition of this potential complication.