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Protection of the global environment and, in particular, providing a sustainable source of clean water is a necessity for human survival. The wide use of heavy metals by modern industries has generated by‐products containing heavy metals. Specifically, large quantities of chromium and arsenic containing compounds are being discharged into the environment. This study has been conducted to determine the feasibility of an electrocoagulation (EC) process using air injection to remove these inorganic elements with iron electrodes. Powder X‐ray diffraction, scanning electron microscopy, and transmission Mössbauer spectroscopy were used to characterize the solid products formed at iron electrodes during EC. The results of this study suggest that magnetite particles and amorphous iron oxyhydroxides are present in the examined EC products. The field pilot‐scale study demonstrated the removal of Cr(VI)/Cr(III) and As(III)/As(V) with an efficiency of more than 99 % from both wastewater and wells.

Abstract:  A new semiquantitative enzyme immunoassay (Platelia Helicobacter pylori; Sanofi Diagnostics Pasteur, France) was evaluated and compared with two other serological assays (Gap-test IgG; Bio-Rad, France; and Cobas Core; Roche, Switzerland) for the diagnosis of Helicobacter pylori infection in children. The three tests were compared with the examination of biopsy samples obtained from 160 dyspeptic subjects (mean age, 9±4.7 years). Discrepant results were studied using an immunoblot technique. The response obtained for the Platelia assay in children was significantly lower than that obtained in a previously described population of 92 adults (Helicobacter pylori-negative mean ratios, 0.376 vs. 0.504, P<0.000783;Helicobacter pylori-positive mean ratios, 1.95 vs. 2.67, P<0.000003). Thus, the optimal cut-off for children (0.80) was lower than the one recommended for adults (1.10). According to the Receiver Operating Characteristic (ROC) curve analysis and to the Wilcoxon value, the Platelia and Cobas Core assays showed the highest discriminatory properties (Wilcoxon value, 0.94 for both) compared with the Gap-test IgG (Wilcoxon value, 0.91). When the newly established cut-off value (0.80) was used, the performance of Platelia was equivalent to that of Cobas Core (sensitivity: 94.4% for each; respective specificities, 86.8% and 90.6%). The Gap-test IgG had a lower sensitivity (maximum, 79%) and a higher specificity (maximum, 95.3%), but there were difficulties in interpretation because its grey zone encompassed 12% of the sera. In conclusion, the results showed good performance of the Platelia Helicobacter pylori assay and confirmed the merit of a specific cut-off value for use of this test in children.

Sera from obligate heterozygotes for deficiency of the C8β subunit of the eighth component of human complement (C8) were analyzed for the molecular composition of C8. The C8α-γ and C8β subunits were separated by SDS-PAGE, visualized by immunoblotting, and the resulting bands were quantitated by laser densitom-etry. The laser densitometric absorption data were set to 100 arbitrary units (AU) for both subunits of pooled normal human sera. The AU values of individual normal sera ranged from 45 to 150 AU for C8α-γ (median 99 AU) and from 45 to 140 AU for C8β (median 101), whereas the C8α-γ/C8β-ratio varied from 0.7 to 1.4. Sera from C8β-deficient heterozygotes differed, as expected, from the normal sera for the markedly reduced levels of C8β (20 to 90 AU, median 55 AU) and for the higher C8α-γ/C8β-ratio (1.3 to 3.5). High voltage agarose gel electrophoresis was used to separate free and C8β-bound C8α-γ. The migration of free and C8β-bound C8α-γ subunit was checked by hemolytic overlay gels and by second dimension SDS-PAGE and immunoblotting. Immunochemical evaluation of C8α-γ using this system revealed about 5–14 free C8α-γ in sera with normal C8 and higher levels, from 33–71, in the C8βD heterozygous sera. Functional analysis confirmed the substantial increase of free C8α-β in the heterozygous group. We conclude that the C8 in C8βD heterozygous sera is characterized by increased amounts of free C8α-γ due to reduced concentrations of the C8β subunit. This finding may help to identify individuals heterozygous for C8β deficiency.

The possible role played by monocytes in the inhibitory effect of calcitriol on phytohemagglutinin (PHA)-stimulated lymphocyte proliferation was assessed by testing the effect of this sterol under different cell culture conditions. Calcitriol had a dose-dependent inhibitory effect on lymphocyte proliferation in concentrations ranging from 10-10 up to 10-8 M. The effect of 10-9 M calcitriol was almost completely abolished by: a) monocyte depletion, b) inhibition of prostaglandin (PG) synthesis by indomethacin, and c) addition of exogenous interleukin-2 (IL-2). These results suggested that the inhibitory effect of calcitriol was mediated through monocytes. This possibility was substantiated by the following observations: a) the calcitriol inhibitory effect was restored when autologous adherent cells were added to monocyte-depleted PBM cells; b) the supernatant of adherent cells cultured for 24 hours in the presence of calcitriol exerted a marked inhibitory effect on lymphocyte proliferation; and c) this effect was not longer evident when adherent cells were cultured in the presence of calcitriol plus indomethacin. These data support the hypothesis that calcitriol acts, at least partially, through the monocytes, inducing an increased release of PG, with subsequent inhibition of IL-2 synthesis, then resulting in a decreased lymphocyte proliferation.

Summary Currently there are no widely accepted criteria for the diagnosis of MCTD. In this work we attempted to define the clinical profile of a group of 68 patients with anti nRNP antibodies, detected by immunoprecipitation in 0.6% agarose. The diagnosis of each collagen vascular disease was established in every patient, who met with the strict diagnostic criteria either at clinical presentation or during the follow-up period. Twenty-eight patients had SLE, 9 had classical erosive RA, three had PSS and one had PM. The only distinctive features in the group of SLE with anti nRNP was an increased incidence of anti Sm antibodies (p<0.05). In the RA group there was a trend towards a high frequency of Raynaud's phenomenon and swollen hands. At clinical presentation twenty-seven patients did not fulfil enough criteria to be diagnosed of any of the well-defined collagen vascular disease. They presented an undifferentiated syndrome, characterized clinically by Raynaud's phenomenon (100%), swollen hands (88.9%) and joint symptoms (88.9%), with scarce tendency of developing severe systemic manifestations. The main laboratory abnormalities in this group were hipergammaglobulinemia, mildly increased ESR, abnormal levels of CIC, negative anti nDNA and anti Sm antibodies, and the virtual absence of hipocomplementemia. During a clinical course of 96±72.5 months only one patient evolved into another collagen disease (SLE). The clinical course in the remaining cases, was stable improving with low doses of prednisone and/or NSAID. We suggest considering this undifferentiated syndrome as a distinct entity, for which the already classical term of MCTD could be reserved.

Summary A woman with CREST syndrome since the age of 35, had 11 and 13 years respectively after her disease onset, two episodes of CVA with residual right side hemiplegia. The angiography revealed segmented stenosis in the left common carotid, right subclavian and left renal arteries. At the age of 49 she developed gangrene of the right foot, requiring below the knee amputation. Pathological examination of the surgical specimen, showed extensive intimal fibrosis of the vessel walls in large and medium size arteries. Involvement of large and medium size arteries is infrequent in scleroderma. The case described illustrates this severe and unusual complication.

This study, which focuses on a plantation, as well as the study by Bidinger et al., which concerns a village, failed to find the marked seasonal changes in food consumption reported for many other parts of the world. It would be a serious mistake to consider that these studies contradict in any way the findings of those who report seasonal variations They are published, however, as a reminder that generalizations cannot be used to predict specific cases and that, conversely, great caution must be used in generalizing from specific cases. The characteristics of the sites in both studies offer adequate explanation of why they did not fit the expected pattern of seasonal variation despite distinct rainy and dry seasons and harvest and non-harvest periods. It should be noted, however, that both Valverde et al. and Bidinger et al. did observe the anticipated marked seasonal differences in morbidity from diarrhoeal and other infectious diseases.

ABSTRACT: Sera from obligate heterozygotes for deficiency of the C8ß subunit of the eighth component of human complement (C8) were analyzed for the molecular composition of C8. The C8a-? and C8ß subunits were separated by SDS-PAGE, visualized by immunoblotting, and the resulting bands were quantitated by laser densitom-etry. The laser densitometric absorption data were set to 100 arbitrary units (AU) for both subunits of pooled normal human sera. The AU values of individual normal sera ranged from 45 to 150 AU for C8a-? (median 99 AU) and from 45 to 140 AU for C8ß (median 101), whereas the C8a-?/C8ß-ratio varied from 0.7 to 1.4. Sera from C8ß-deficient heterozygotes differed, as expected, from the normal sera for the markedly reduced levels of C8ß (20 to 90 AU, median 55 AU) and for the higher C8a-?/C8ß-ratio (1.3 to 3.5). High voltage agarose gel electrophoresis was used to separate free and C8ß-bound C8a-?. The migration of free and C8ß-bound C8a-? subunit was checked by hemolytic overlay gels and by second dimension SDS-PAGE and immunoblotting. Immunochemical evaluation of C8a-? using this system revealed about 5–14% free C8a-? in sera with normal C8 and higher levels, from 33–71%, in the C8ßD heterozygous sera. Functional analysis confirmed the substantial increase of free C8a-ß in the heterozygous group. We conclude that the C8 in C8ßD heterozygous sera is characterized by increased amounts of free C8a-? due to reduced concentrations of the C8ß subunit. This finding may help to identify individuals heterozygous for C8ß deficiency.

The use of implants in retaining orbital prostheses has gained favor in recent years. Not all patients may be candidates for use of medical adhesives or anatomic retention as advocated by some. Osseointegrated implants offer an alternative method for retaining an orbital prosthesis. Because of the confining nature of an orbital defect, it may be difficult to reproduce the spatial arrangement of implants accurately with one impression. The technique presented here accomplishes the objectives of minimal trauma to the tissues, accuracy, and elimination of consecutive impression technique.

In 1991, Abramson et alreported a new syndrome of acute reversible hypoxemia (ARH) in patients with severe SLE (systemic lupus erythematosus). This syndrome was characterized by an unexplained abnormal value of arterial blood gases (ABG) without obvious parenchymal lung disease, and a good response to high-dose corticosteroid therapy. After we became aware of this entity, four of 16 patients admitted to our unit because of a SLE flare presented respiratory symptoms and abnormal ABG consistent with ARH. In none of our patients were the pulmonary manifestations a prominent clinical feature of the disease. Furthermore, in two of them, treatment with high-dose aspirin and moderate to low doses of corticosteroids was sufficient to improve the pulmonary manifestations, but not to control the systemic activity of the disease. Therefore, we believe that this new pulmonary finding more than a clinically independent syndrome represents an index of disease activity in patients with SLE.

The gene encoding endothiapepsin (EAP), an extracellular aspartic proteinase from the filamentous ascomycete Cryphonectria parasitica, was expressed into Saccharomyces cerevisiae. Efficient secretion of an active and correctly processed enzyme was achieved when expressing the entire cDNA encoding prepro-EAP under the control of the galactose-inducible GRAP1 yeast promoter. Since three independent, site-directed mutations of EAP, including the substitution of an aspartyl catalytic residue, resulted in the intracellular accumulation of zymogen forms, we assumed that the EAP propeptide was autocatalytically processed. As a prerequisite to further improve the specificity of EAP, we therefore attempted to bypass this self-processing step in three different ways: 1) introduction of a Kex2-like recognition site between the pro and the mature part, 2) deletion of the prosequence (pre-EAP), and 3) co-expression in trans of the pre-EAP with its preprosequence. No improvement in the secretion of mutant enzymes was obtained in any of these experiments. As an alternative, we finally replaced the EAP processing site by the chymosin cleavage sequence of kappa-casein. Such a modification remained efficient in directing the secretion of active EAP only when a putative alpha-helix structural motif was conserved at the C terminus of the pro region.

Reverse transcriptase (RT) was first discovered as an essential catalyst in the biological cycle of retroviruses. However, in the past years evidence has accumulated showing that RTs are involved in a surprisingly large number of RNA-mediated transpositional events that include both viral and nonviral genetic entities. Although it is probable that some RT-bearing genetic elements like the different types of AIDS viruses and the mammalian LINE family have arisen in recent geological times, the possibility that reverse transcription first took place in the early Archean is supported by (1) the hypothesis that RNA preceded DNA as cellular genetic material; (2) the existence of homologous regions of the subunit tau of the E. coli DNA polymerase III with the simian immunodeficiency virus RT, the hepatitis B virus RT, and the ß' subunit of the E. coli RNA polymerase (McHenry et al. 1988); (3) the presence of several conserved motifs, including a 14-amino-acid segment that consists of an Asp-Asp pair flanked by hydrophobic amino acids, which are found in all RTs and in most cellular and viral RNA polymerases. However, whether extant RTs descend from the primitive polymerase involved in the RNA-to-DNA transition remains unproven. Substrate specificity of the AMV and HIV-1 RTs can be modified in the presence of Mn2+, a cation which allows them to add ribonucleotides to an oligo (dG) primer in a template-dependent reaction. This change in specificity is comparable to that observed under similar conditions in other nucleic acid polymerases. This experimentally induced change in RT substrate specificity may explain previous observations on the misincorporation of ribonucleotides by the Maloney murine sarcoma virus RT in the minus and plus DNA of this retrovirus (Chen and Temin 1980). Our results also suggest that HIV-infected macrophages and T-cell cells may contain mixed polynucleotides containing both ribo- and deoxyribonucleotides. The evolutionary significance of these changes in substrate specificities of nucleic acid polymerases is also discussed.

Background. In a significant number of patients the differential diagnosis between elderly-onset rheumatoid arthritis (EORA) and polymyalgia rheumatica (PMR) is very difficult because of the lack of specific serum markers. Anti-cyclic citrullinated peptide antibodies (anti-CCP Abs) have recently been shown to be highly specific for rheumatoid arthritis (RA). This is the first study addressing the utility of these antibodies in the differential diagnosis between EORA and PMR.Methods. Serum samples from 57 EORA patients and 49 PMR patients were studied for the presence of anti-CCP Abs and rheumatoid factor (RF). As controls, samples from 41 RA patients (age at onset <60 yr) and 24 aged healthy subjects were analysed.Results. Sixty-five per cent of EORA patients had anti-CCP Abs, whereas none of the PMR patients or the aged healthy subjects was positive for those antibodies. Ten of the EORA patients started with polymyalgic symptoms and two of them were positive for anti-CCP Abs. Interestingly, there was a significant correlation between anti-CCP Abs and RF in EORA but not in young RA patients.Conclusions. The presence of anti-CCP Abs in a patient with clinical symptoms of PMR must be interpreted as highly suggestive of EORA.

&lt;it>Objective&lt;/it>. To investigate the pathogenic mechanism of reactive arthritis after instillation of Calmette–Guérin bacillus &lpar;BCG&rpar;. Although the clinical features of reactive arthritis after BCG therapy are well described, only a few reports have studied the possible pathogenic mechanisms. &lt;it>Methods&lt;/it>. We analysed by flow cytometry the phenotype and T&hyphen;cell receptor &lpar;TCR&rpar; expression of peripheral blood &lpar;PB&rpar; and synovial fluid &lpar;SF&rpar; T cells in a patient who developed reactive arthritis &lpar;ReA&rpar; following intravesical BCG immunotherapy for bladder cancer. The proliferative response of short&hyphen;term T&hyphen;cell lines &lpar;TCL&rpar; from PB of this patient to mycobacterial antigens was tested by bromodeoxyuridine incorporation. &lt;it>Results&lt;/it>. CD4&plus; and CD8&plus; SF T cells with activated and memory phenotype were observed at the onset of arthritis. We were able to detect BV&hyphen;restricted expansion of CD8&plus; T cells in PB &lpar;BV17&rpar; and in SF &lpar;BV5S1 and BV12&rpar;. The percentage of PB and SF CD8&plus; T cells that expanded diminished when the symptoms remitted. The strongest response of CD4&plus; TCL from the patient &lt;it>in vitro&lt;/it> was obtained for human hsp&hyphen;60 in an inversely dose&hyphen;dependent manner. Very important was the finding that CD8&plus; TCL from the patient demonstrated no proliferative response to any antigenic challenge that was reversed after the addition of exogenous interleukin 2. &lt;it>Conclusion&lt;/it>. Although the identity of the stimulating antigen that led to the expansions observed in this patient is not clarified by the present data, both CD4&plus; and CD8&plus; T cells might play a role in the development of ReA following intravesical administration of BCG.