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We use perturbation theory to obtain neutrino oscillation probabilities, including the standard mass-mixing paradigm and non-standard neutrino interactions (NSI). The perturbation is made on the standard parameters and sin2(θ13) and on the non-diagonal NSI parameters, but keeps diagonal NSI parameters non-perturbated. We perform the calculation for the channels νμ → νe and νμ → νμ. The resulting oscillation formulas are compact and present functional structure similar to the standard oscillation (SO) case. They apply to a wide range in the allowed NSI space of parameters and include the previous results from perturbative approaches as limit cases. Also, we use the compact formulas we found to explain the origin of the degeneracies in the neutrino probabilities in terms of the invariance of amplitude and phase of oscillations. Then we determine analytically the multiple sets of combinations of SO and NSI parameters that result in oscillation probabilities identical to the SO case. [ABSTRACT FROM AUTHOR]

Biotinylation is proposed for the identification of surface proteins in Schistosoma mansoni using the streptavidin-HRP conjugate for the detection of labeled polypeptides. However, control samples also showed several endogenous biotinylated polypeptides. In an attempt to determine the possibility of nonspecific binding between the streptavidin-HRP conjugate and polypeptides from S. mansoni, the conjugate was blocked with biotinamidecaproate-N-hydroxysuccinimide ester (BcapNHS) before biotin-streptavidin blotting. No bands were detected on the nitrocellulose sheet, demonstrating the specific recognition of biotin by the streptavidin present in the conjugate. Whole cercariae and cercarial bodies and tails showed several endogenous biotinylated polypeptides. The biotin concentration was 13 micrograms/190,000 cercariae. Adult worms presented less endogenous biotinylated polypeptides than cercariae. These results may be due to changes in the environment from aerobic to anaerobic conditions when cercarial bodies (schistosomula) are transformed into adult worms and a decrease in CO2 production may occur. Cercariae, cercarial bodies and adult male worms were examined by transmission electron microscopy employing an avidin-colloidal gold conjugate for the detection of endogenous biotin. Gold particles were distributed mainly on the muscle fibers, but dispersed granules were observed in the tegument, mitochondria and cytosol. The discovery of endogenous biotin in S. mansoni should be investigated in order to clarify the function of this vitamin in the parasite.

Familial and secondary deficiency of plasma lecithin-cholesterol acyltransferase (LCAT) produce circulating lipoprotein particles with gross structural and compositional abnormalities; these have adverse effects on a variety of cellular functions. Factors affecting hepatic synthesis and secretion of this plasma enzyme are largely unknown but, potentially, some of them can be investigated with monospecific antibodies. In the present study, enzymically active LCAT was purified 40,000-fold from human plasma and then used to raise polyclonal antibodies in New Zealand White rabbits. Addition of this antiserum (1 microliter) to human plasma (25 microlitres) completely inhibited LCAT activity, although it was less effective against plasma from other species. The antibodies appeared to be monospecific to plasma LCAT. They gave a single precipitin arc by crossed immunoelectrophoresis, while immunodiffusion established that there was no cross-reactivity with several apolipoproteins or with serum albumin. Moreover, the antiserum was successfully used to detect LCAT in normal human plasma by Laurell rocket immunoelectrophoresis. By contrast, Western blotting of plasma proteins using whole LCAT antiserum was largely unsuccessful because of high background staining, although this could be substantially reduced by use of an IgG fraction. However, the whole antiserum readily immunoprecipitated LCAT secreted into the culture medium of HepG2 cells, a human hepatoblastoma cell line, pre-labelled with [35S]methionine, the [35S]-labelled LCAT appearing as a narrow 65-kDa protein band by electrophoresis and fluorography. We conclude that polyclonal antibodies may be an important tool to investigate the characteristics and underlying mechanisms of secondary LCAT deficiencies, including those associated with hepatic cirrhosis and schistosomiasis.

The Camaçari Petrochemical Complex (CPC) is the biggest and most important industrial complex of the northeastern region of Brazil. At present, its 54 companies employ directly and indirectly about 50,000 people. Used there as solvent and raw material, compounds such as benzene and its homologues n-hexane, haloalkanes, and some alcohols have as their prime targets the central and peripheral nervous systems. Despite widespread use of these chemicals, the workers are little aware of their toxicity, and the evaluation of exposure to them has only recently become a worrisome issue. This paper discusses the contamination of occupational environments in some industries of the CPC, as well as the neurobehavioral impairment that could be found among their workers.

In 1980, a survey of lead poisoning was carried out among 592 children aged 1 to 9 years living within 900 m of a lead smelter in Santo Amaro, Brazil. From 1980 to 1985, the lead smelter carried out a number of major improvements aimed at reducing environmental pollution. In January, 1985, a second survey was carried out among a sample of 250 children living in this same geographical area. The geometric mean of zinc protoporphyrin (ZPP) concentration in whole blood was 1.17 (standard deviation = 1.5) mumol l-1. Blood lead concentrations (PbB) determined in a subsample of 53 children had an arithmetic mean and standard deviation of 1.77 +/- 1.00 mumol l-1, with 22 children showing PbB greater than or equal to 1.68 mumol l-1. Twenty-nine (11.6%) of the 250 children lived in houses where the lead content of the soil was greater than 10,000 ppm, and they presented higher ZPP levels than the rest of the population. Children with the habit of pica for soil had elevated ZPP levels. Comparing the results from the 1980 and 1985 surveys, slight improvements in ZPP and PbB levels were observed. However, new cases of lead poisoning are still occurring in the area. The soil is highly contaminated by lead and represents a long-lasting risk factor for child intoxication.

In a cross-sectional study, concentrations of cadmium in hair (CdH) were determined for 263 children aged 1-9 years, living less than 900 m from a lead smelter in Santo Amaro, Brazil. The mean CdH level was significantly higher when individuals with the following characteristics were considered: female, racial group "dark" or "medium", and children of lead workers. The mean CdH value did not vary significantly according to nutritional status or iron status or hair type. Hair Cd levels increased significantly in relation to an increase in cadmium concentration in soil. An increase of 0.024 ppm in mean CdH level was estimated for each 1 ppm increase in the cadmium concentration in soil. However, children with the habit of pica had only a slight increase in CdH levels, when compared with those without the habit. The marked variations observed in CdH levels suggest the possibility of using them as an epidemiological index in situations of intense environmental pollution.

The protein sequencing of tryptic peptides from purified human lecithin: cholesterol acyltransferase (LCAT) identified sufficient amino-acid sequence to construct a corresponding mixed oligonucleotide probe. This was used to screen an adult human cDNA liver library, from which incomplete cDNA clones were isolated. The DNA sequence of these clones allows the prediction of the entire amino-acid sequence of the mature LCAT enzyme. The mature protein consists of 416 amino acids and contains several marked stretches of hydrophobic residues and four potential glycosylation sites. The cDNA probe detects LCAT mRNA sequences approx. 1500 bases long in human liver, but not intestine, RNA. The cDNA probe was used to isolate LCAT genomic recombinants from a human genomic library. Southern blotting data, and restriction site mapping, suggest that there is a single human LCAT structural gene between 4.3 and 5.5 kb in size.