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Notes: Hydrogenated and fluorinated amorphous silicon films (a-Si:H,F) have been deposited in a parallel-plate rf plasma reactor fed with SiF4-H2 mixtures. The plasma phase characterization has been performed by optical emission spectroscopy for the analysis of the emitting species (SiF*3,SiF*2,SiF*,H*, and H*2), mass spectrometry for the analysis of stable species, and Langmuir electrical probes for the evaluation of electron density (ne) and temperature (kTe). The deposition rate (rD) has been monitored by laser interferometer. The effect of the rf power, gas composition, total pressure, and dopant (B2H6, PH3) addition on the plasma phase composition and on the film growth rate has been studied. The data have been discussed on the basis of a chemical model where the chemisorption of SiF4 and SiF2 and the subsequent interaction with H atoms are the determinant steps also from the kinetic point of view. It has been found that the rate equation rD ∝ [H][SiF2] is able to fit the experimental results.

Notes: IgG antibody response to the inhalant allergen Parietaria judaica (Pj) and IgG subclass distribution were studied in 82 normal subjects, divided into three groups according to age (0–1, 1–20, and 20–60 years) and in 32 allergic subjects aged 20–60 years. Both normal and allergic subjects showed an IgG response, and all had IgG1 antibodies specific for PjE. Serum IgG2, IgG3, and IgG4 against PjE were detectable in 36%, 46%, and 22% of normal subjects, and in 58%, 31%, and 65% of allergic subjects, respectively. A significant difference in class distribution between allergic and age-matched normal subjects was found only for IgG4 antibodies against PjE (65% and 17%; P〈0.01). The ELISA results were also analyzed quantitatively, taking into account the relative proportion of specific antibodies. Thus, in normal subjects IgG1 antibodies showed a decreasing trend as the age rose, while no differences according to the age of the subject were found for IgG2 and IgG4. When data from allergic subjects (20–60 years) and the age-matched normal group were compared, they were different for the relative percentage of IgG2 only, showing for this a significantly lower value (P〈 0.001). The present data indicate that normal and allergic subjects show differences in the IgG isotype distribution depending on their sensitivity and duration of allergen exposure.

Notes: Measles vaccines are prepared in chick embryo fibroblast culture and used throughout the world. Since 1963 dramatic reductions in the incidence of measles have been observed where the vaccination was extensively applied in the pediatric population. The best results were observed when the target population in the initial phase was that which produced over 90% of cases in the pre-vaccinal era. A possible limiting factor to the diffusion of measles vaccination is the assumption that allergy to egg proteins is a contraindication. In this paper current knowledge about the safety of measles immunization in children with egg allergy is discussed.

Notes: The aim of the present study was to investigate the antibody response to oral poliovirus immunization, and to evaluate the infection morbidity in a group of infants with a positive family history of atopy who were soy-protein-formula fed during the first 6 months of life. We have selected and followed from birth to 4 yr, 107 babies, 18 of whom were exclusively soy-protein-formula fed during the first 6 months of life. All infants were seen at our clinic at the ages of 1, 3, 6, 9, and 12 months, and once-a-year afterwards. They regularly received the oral vaccine against polioviruses at the ages of 3, 5 and 12 months. At age 6, 12 and 24 months, poliovirus type 1, 2 and 3 antibodies were detected. There was no significant difference of seroconversion in the babies, breast, soy or breast and soy fed. Furthermore, no increase in infection morbidity was observed in the soy-protein-formula fed infants. Our data shows that soy-protein-formula feeding in the first 6 months of life does not induce any abnormal antibody response to the oral poliovirus vaccination, as well as no increase in infection morbidity.

Notes: Abstract. Recent studies of microbial epidemiology emphasizing the genetic organization and distribution of organisms associated with orofacial infections have led to new insights into the possible origins of pathogenicity. Studies into genetic heterogeneity, acquisition and transmission of these organisms have been markedly advanced by the utilization of the powerful technique of genomic DNA fingerprinting. Characteristic fingerprints for each bacterial isolate can be produced by cleavage of high molecular weight genomic DNA by restriction endonucleases. It is assumed that each DNA fingerprint represents a clonal type. In this report, we review and analyze studies of the epidemiology of bacteria associated with orofacial infections with an emphasis on periodontal disease. Studies of nontypable (NT) Haemophilus influenzae associated with recurrent otitis media illustrate the utility of this technique. DNA fingerprinting clearly demonstrates genetic heterogeneity of NT H. influenzae isolates, and clonality of infection of any individual. Furthermore, DNA fingerprinting has shown that the same clonal type is seen in siblings concurrently suffering from otitis media, suggesting horizontal transmission within the family. Studies of mutans Streptococci also show extensive genetic heterogeneity and show vertical transmission of a predominant clonal type only from mother to infant, but not from father to infant. Studies of Actinobacillus actinomycetemcomitans show considerable genetic heterogeneity among monkey isolates. Thus far, three clonal types have been reported with DNA fingerprinting among isolates from periodontal patients, but additional genetic heterogeneity can be found using specific DNA fragments as probes in hybridization experiments. Intrafamilial transmission of A. actinomycetemcomitans has been demonstrated. Porphyromonas (Bacteroides) gingivalis shows extensive genetic heterogeneity and case reports suggest clonal infection of any one individual. In contrast, results with DNA fingerprinting of Eikenella corrodens, Fusobacterium nucleatum, and Bacteroides intermedius show that individuals may be infected with 2 or more clonal types. These studies point to the great potential of DNA fingerprinting for investigating the epidemiology of putative orofacial pathogens. Such studies with periodontal microorganisms will likely reveal steps in the acquisition, intraoral and person-to-person transmission, which then could possibly be inhibited or interfered with to prevent periodontal disease or its recurrence.