Microwave sulphating roasting was applied to zinc oxide fume from a fuming furnace for the removal of F and Cl. The effect of important parameters such as roasting temperature, holding time. and vapour flow were investigated and the process conditions were optimized using response surface methodology. The results showed that the effects of roasting temperature and holding time on the removal efficiency of F and Cl were most significant, and the effect of vapour flow is of much lower importance. The defluorination and dechlorination efficiency increased rapidly as the roasting temperature and holding time increased, while the vapour flow had little effect. The defluorination efficiency could reach 91.3% while the dechlorination efficiency could reach 89.5%, under the process conditions of roasting temperature 655°C, holding time 65.2 minutes, and vapour flow of 6.8 ml/min. The results showed that the removal of F and Cl from zinc oxide fume using a microwave direct roasting process is feasible and reliable.

ABSTRACT We report the case of a 45-year old woman with a painless soft tissue mass on the left side of her neck. At surgery, the lesion was solid and rubbery and revealed grey-white fibrous areas. It was pathologically confirmed as an elastofibroma, a rare, benign soft tissue tumour that is most commonly encountered in patients more than 55 years of age. Elastofibroma arising from connective tissue and usually found in the subscapular region is extremely rare in the neck. The pathogenesis of elastofibroma is still unclear but increased mechanical stress or nutritional derangement consequent to vascular involvement and hereditary factors may predispose to this lesion. Marginal excision is the treatment of choice in symptomatic patients.

RESUMEN Reportamos el caso de una mujer de 45 años con una masa de tejido suave sin dolor en el lado izquierdo del cuello. Al realizarse la cirugía, se halló que la lesión era sólida y gomosa, y presentaba áreas fibrosas de color gris-blanco. El análisis patológico confirmó que se trataba de un elastofibroma: un tumor del tejido blando, raro y benigno, que se encuentra más comúnmente en pacientes de más de 55 años de edad. Los elastofibromas que provienen del tejido conjuntivo y que generalmente se encuentran en la región subescapular, son extremadamente raros en el cuello. La patogénesis del elastofibroma no está todavía clara, pero el aumento del estrés mecánico o los desarreglos nutricionales consecuencia de problemas vasculares y factores hereditarios, pueden predisponer a esta lesión. La extirpación marginal es el tratamiento de elección en pacientes sintomáticos.

Our objective was to clone, express and characterize adult Dermatophagoides farinae group 1 (Der f 1) allergens to further produce recombinant allergens for future clinical applications in order to eliminate side reactions from crude extracts of mites. Based on GenBank data, we designed primers and amplified the cDNA fragment coding for Der f 1 by nested-PCR. After purification and recovery, the cDNA fragment was cloned into the pMD19-T vector. The fragment was then sequenced, subcloned into the plasmid pET28a(+), expressed in Escherichia coli BL21 and identified by Western blotting. The cDNA coding for Der f 1 was cloned, sequenced and expressed successfully. Sequence analysis showed the presence of an open reading frame containing 966 bp that encodes a protein of 321 amino acids. Interestingly, homology analysis showed that the Der p 1 shared more than 87% identity in amino acid sequence with Eur m 1 but only 80% with Der f 1. Furthermore, phylogenetic analyses suggested that D. pteronyssinus was evolutionarily closer to Euroglyphus maynei than to D. farinae, even though D. pteronyssinus and D. farinae belong to the same Dermatophagoides genus. A total of three cysteine peptidase active sites were found in the predicted amino acid sequence, including 127-138 (QGGCGSCWAFSG), 267-277 (NYHAVNIVGYG) and 284-303 (YWIVRNSWDTTWGDSGYGYF). Moreover, secondary structure analysis revealed that Der f 1 contained an a helix (33.96%), an extended strand (17.13%), a ß turn (5.61%), and a random coil (43.30%). A simple three-dimensional model of this protein was constructed using a Swiss-model server. The cDNA coding for Der f 1 was cloned, sequenced and expressed successfully. Alignment and phylogenetic analysis suggests that D. pteronyssinus is evolutionarily more similar to E. maynei than to D. farinae.