FS12.1Allergic contact dermatitis from plastic gloves

Plastic gloves are made of polymers including polyvinylchloride, polyvinylalcohol, polyethylene and polyvinylacetate. Additives such as plasticizers, stabilizers, UV light absorbers, fungicides, bactericides, flame retardants and colourants are added to the polymer, and these are potential allergens. Contact allergy to plastic gloves is rare. The allergen responsible for the sensitization usually remains unknown. An organic pigment, Irgalite Orange F2G, and bisphenol A have both caused contact allergy from household‐type PVC gloves. 1 patient with allergic contact dermatitis from his PVC gloves reacted also to tricresyl phosphate and triphenyl phosphate, chemicals known to be used as plasticizers in PVC. A plasticizer, di(2‐ethylhexyl) phthalate (DOP), caused 1 case of contact urticaria from the vinyl chloride slip guard of cotton gloves. 1 patient with contact urticaria from his polyethylene gloves reacted to 3 antioxidants, octadecanoic acid methyl ester and di‐tertiary butyl phenol of the gloves on scratch testing. We report 3 additional cases of allergic contact dermatitis from PVC gloves due to bisphenol A. 2 of the patients reacted also to para‐tertiary butyl catechol, a polymerization inhibitor in PVC. In chemical analysis, the connection between sensitization to para‐tertiary butyl catechol and the use of vinyl gloves could not be proven. We analysed 16 brands of disposable PVC gloves for medical use, covering at least 80% of the Finnish market. We found a very small amount of bisphenol A in 1 brand, and no para‐tertiary butyl catechol in any of the gloves. However, bisphenol A should be remembered as a possible allergen in PVC gloves.     

A micro-PET/CT approach using O-(2-[F]fluoroethyl)-l-tyrosine in an experimental animal model of F98 glioma for BNCT

The present study focuses on a micro-PET/CT application to be used for experimental Boron Neutron Capture Therapy (BNCT), which integrates, in the same frame, micro-CT derived anatomy and PET radiotracer distribution. Preliminary results have demonstrated that ¹⁸F-fluoroethyl-tyrosine (FET)/PET allows the identification of the extent of cerebral lesions in F98 tumor bearing rat. Neutron autoradiography and α-spectrometry on axial tissues slices confirmed the tumor localization and extraction, after the administration of fructose–boronophenylalanine (BPA). Therefore, FET–PET approach can be used to assess the transport, the net influx, and the accumulation of FET, as an aromatic amino acid analog of BPA, in experimental animal model. Coregistered micro-CT images allowed the accurate morphological localization of the radiotracer distribution and its potential use for experimental BNCT.     

O等位基因引起ABO基因型与表现型定型差异

保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.     

Immunological and Antiviral Responses After Therapeutic DNA Immunization in Chronic Hepatitis B Patients Efficiently Treated by Analogues

A substudy of a phase I/II, prospective, multicenter clinical trial was carried out to investigate the potential benefit of therapeutic vaccination on hepatitis B e antigen-negative patients with chronic hepatitis B (CHB), treated efficiently with analogues. Patients were randomized in 2 arms, one receiving a hepatitis B virus (HBV) envelope DNA vaccine, and one without vaccination. At baseline, HBV-specific interferon (IFN)-γ–producing T cells were detected in both groups after in vitro expansion of peripheral blood mononuclear cells. Vaccine-specific responses remained stable in the vaccine group, whereas in the control group the percentage of patients with HBV-specific IFN-γ–producing T cells decreased over time. The vaccine-specific cytokine-producing T cells were mostly polyfunctional CD4⁺ T cells, and the proportion of triple cytokine-producer T cells was boosted after DNA injections. However, these T-cell responses did not impact on HBV reactivation after stopping analogue treatment. Importantly, before cessation of treatment serum hepatitis B surface antigen (HBsAg) titers were significantly associated with DNA or HBsAg clearance. Therapeutic vaccination in CHB patients with persistent suppression of HBV replication led to the persistence of T-cell responses, but further improvements should be searched for to control infection after treatment discontinuation.     

Identification of the novel narrow-spectrum beta-lactamase SCO-1 in Acinetobacter spp. from Argentina

By studying the beta-lactamase content of several Acinetobacter spp. isolates from Argentina, producing the expanded-spectrum beta-lactamases (ESBL) VEB-1a or PER-2, a novel Ambler class A beta-lactamase gene was identified. It encoded the narrow-spectrum beta-lactamase SCO-1, whose activity was inhibited by clavulanic acid. SCO-1 hydrolyzes penicillins at a high level and cephalosporins and carbapenems at a very low level. beta-Lactamase SCO-1 was identified from unrelated VEB-1a-positive or PER-2-positive Acinetobacter spp. isolates recovered from three hospitals. The bla(SCO-1) gene was apparently located on a plasmid of ca. 150 kb from all cases but was not associated with any ESBL-encoding gene. The G+C content of the bla(SCO) gene was 52%, a value that does not correspond to that of the A. baumannii genome (39%). beta-Lactamase SCO-1 shares 47% amino acid identity with CARB-5 and ca. 40% with the enzymes TEM, SHV, and CTX-M. A gene encoding a putative resolvase was identified downstream of the bla(SCO-1) gene, but its precise way of acquisition remains to be determined.