Distribution patterns of organic pollutants and microbial processes in marine sediments across a gradient of anthropogenic impact.

Marine sediments are part of the hydrological cycle and the ultimate storage compartment of land-derived organic matter, including pollutants. Since relevant microbially-driven processes occurring at benthic level may affect the quality of the overall aquatic system, the necessity for incorporating information about microbial communities functioning for ecosystem modelling is arising. The aim of this field study was to explore the links occurring between sediment contamination patterns by three selected class of organic pollutants (Polycyclic Aromatic Hydrocarbons, PAHs, Nonylphenols, NPs, Bisphenol A, BPA) and major microbial properties (Prokaryotic Biomass, PB; total living biomass, C-ATP; Prokaryotic C Production rate, PCP; Community Respiration rate, CR) across a gradient of anthropogenic pollution. Sediments were sampled from 34 sites selected along 700 km of the western coastline of the Adriatic Sea. Organic contamination was moderate (PAHs <830 ng g-1; NPs <350  ng g-1; BPA <38  ng g-1) and decreased southward. The amount of PAHs-associated carbon (C-PAHs) increased significantly with sediment organic carbon (OC), along with microbial functional rates. The negative relation between PCP/CR ratio and OC indicated the shift toward oxidative processes in response to organic pollution and potential toxicity, estimated as Toxic Equivalents (TEQs). Our outcomes showed that sediment organic contamination and benthic microbial processes can be intimately linked, with potential repercussions on CO2 emission rates and C-cycling within the detritus-based trophic web.

Groundwater geochemistry and microbial community structure in the aquifer transition from volcanic to alluvial areas.

Groundwaters may act as sinks or sources of organic and inorganic solutes, depending on the relative magnitude of biochemical mobilizing processes and groundwater-surface water exchanges. The objective of this study was to link the lithological and hydrogeological gradients to the aquatic microbial community structure in the transition from aquifer recharge (volcanic formations) to discharge areas (alluvial deposits). A field-scale analysis was performed along a water table aquifer in which volcanic products decreased in thickness and areal extension, while alluvial deposits became increasingly important. We measured the main groundwater physical parameters and the concentrations of major and trace elements. In addition, the microbial community structure was assessed by estimating the occurrence of total coliforms and Escherichia coli, the prokaryotic abundance, the cytometric and phylogenetic community composition. The overall biogeochemical asset differed along the aquifer flow path. The concentration of total and live prokaryotic cells significantly increased in alluvial waters, together with the percentages of Beta- and Delta-Proteobacteria. The microbial propagation over a theoretical groundwater travel time allowed for the identification of microbial groups shifting significantly in the transition between the two different hydrogeochemical facies. The microbial community structure was intimately associated with geochemical changes, thus it should be further considered in view of a better understanding of groundwater ecology and sustainable management strategies.

Effects of small-scale turbulence on bacteria: a matter of size.

We examined the influence of small-scale turbulence and its associated shear on bacterioplankton abundance and cell size. We incubated natural microbial assemblages and bacteria-only fractions and subjected them to treatments with turbulence and additions of mineral nutrients and/or organic carbon. Bacterial abundance was not affected directly by turbulence in bacteria-only incubations. In natural microbial assemblage incubations, bacterial concentrations were higher under turbulence than in still-water controls when nutrients were added. In general, in the turbulence treatments bacteria increased significantly in size, mainly due to elongation of cells. The addition of inorganic nutrients had a negative effect on bacterial size, but a significantly positive effect on abundance independently of other factors such as turbulence and the presence of predators. Flagellate grazing did not trigger an increase in bacterial size as a grazing resistance response in unmixed containers. With the addition of organic carbon, bacteria elongated and partly settled to the bottom of the containers, in both the turbulent and still treatment, but bacterial abundance did not further increase. Furthermore, bacteria aggregated in the turbulence treatments after the second day of incubation even in the absence of other components of the microbial community. We found that turbulence and the associated shear increase bacterial size and change bacterial morphology, at least under certain nutrient conditions. This might be due to a physiological response (enhanced growth rate and/or unbalanced growth) or due to the selection of opportunistic strains when organic carbon is in excess compared to mineral nutrients. We suggest that shear associated with turbulent flow enhances the DOM flux to bacteria directly as well as indirectly through enhanced grazing activity and photosynthetic release. The formation of bacterial aggregates and filaments under turbulence might give selective advantage to bacteria in terms of nutrient uptake and grazing resistance.

[Immunohistochemical analysis of the expression of main adhesion molecules and tumor necrosis factors in the synovial membrane of psoriatic arthritis]. / Analisi immunoistochimica dell'espressione delle principali molecole di adesione e dei fattori di necrosi tumorale a livello della membrana sinoviale nell'artrite psoriasica.

OBJECTIVE: To define the expression and pattern of the synovial distribution of adhesion molecules such as E-selectin, ICAM-1 and VCAM-1 and of TNFalpha and TNFbeta cytokines in psoriatic arthritis (PsA), according to the synovitis duration. METHODS: Cryostatic sections of the synovial membrane tissue samples were stained for the different antibodies using a standard three-stage-immunoperoxidase-labeling technique. RESULTS: E-selectin grade of staining was higher in those patients with a shorter disease duration compared to longstanding synovitic specimens, as well as ICAM-1 expression. On the contrary a higher VCAM-1 positivity was mainly found in longstanding PsA patients. Anti-TNFalpha positivity was found almost in all the specimens with no difference among the two groups, while the intensity of anti-TNFbeta positivity was globally higher in longstanding cases. CONCLUSIONS: Different adhesion molecules may separately participate to the synovitic process in the different phases of PsA, leading to the hypothesis of their different involvement during the disease evolution. Moreover the upregulation of TNFalpha and TNFbeta gives evidence to their local proinflammatory effect within the synovium and to their role in perpetuating the PsA synovitis.

Class specific rheumatoid factors and antiphospholipid syndrome in systemic lupus erythematosus.

The relationship of rheumatoid factors (RF) with antiphospholipid syndrome (aPLS) and anticardiolipin antibodies (aCL) has rarely been investigated in systemic lupus erythematosus (SLE). We found IgM-RF, IgG-RF, IgA-RF, IgM-aCL, IgG-aCL, IgA-aCL, respectively, in 35.4%, 35.4%, 33.8%, 23.1%, 23.1%, 20.0% of 65 SLE patients. Class specific RFs were negatively associated (P<0.05) with IgG-aCL. The frequency of definite or probable aPLS according to Alarcon-Segovia classification criteria was significantly (P<0.05) different (8.7% vs 30.9%) in patients with or without IgG-RF. Among the other clinical features of SLE, we found that patients with IgG-RF, compared to patients lacking this autoantibody, showed a lower frequency (P<0.05) of serositis (21.7% vs 52.4%) and hematologic (52. 2% vs 80.9%) disorders. The levels of IgG-RF and IgM-RF negatively correlated with the number of ARA criteria (P<0.05) but not with the indices of diseases activity or damage. Our study shows that in SLE the presence of RFs are not markers of severity of the disease, but the negative association between IgG-RF and IgG-aCL suggests a distinct role of these autoantibodies in the pathology of SLE, whereas the presence of IgG isotype may identify a subset of SLE patients having a lower risk to develop some clinical manifestations such as aPLS.

Changes of glycosylation of serum proteins in Sjögren's syndrome: correlation with interleukin-6 and soluble interleukin-2 receptor.

A strong increase of the affinity for concanavalin A (Con A) of serum alpha 2-macroglobulin, a non-acute-phase protein, was observed by lectin blotting in patients with Sjögren's syndrome (SS). On the contrary, the total Con A reactivity of serum proteins, measured by enzyme-linked lectin assay, was not augmented in SS, compared with normal donors, probably because positive changes of certain proteins were balanced by negative changes of others, as suggested by lectin blotting analysis. However, a significant increase of total Con A reactivity occurred in subjects with increased serum concentrations of soluble interleukin (IL)-2 receptor, compared with patients with normal concentrations of this marker of disease activity. On the other hand, the same parameter did not appear to be different in patients with normal or increased serum concentrations of IL-6, indicating that this cytokine was not probably responsible for the changes of glycosylation described here.

Changes of glycosylation of serum proteins in psoriatic arthritis, studied by enzyme-linked lectin assay (ELLA), using concanavalin A.

Changes of glycosylation of serum proteins of patients with psoriatic arthritis were detected by lectin blotting and a new enzyme-linked lectin assay (ELLA) using concanavalin A (Con A). A good linear correlation was found between the total Con A-reactivity of serum and the serum levels of C-reactive protein and interleukin-6, which is known to regulate the glycosylation pattern of proteins upon inflammation. A good linear correlation was also observed between the immunoreactivity of alpha 1-antitrypsin, measured by ELISA, using a monoclonal antibody sensitive to glycosylation changes, and the erythrocyte sedimentation rate and the serum concentrations of soluble interleukin-2 receptor, an index of lymphocyte activation which correlated with some inflammatory parameters of disease activity. These protein changes, which are described here for the first time, deserve to be studied in further detail in view of their possible clinical applications.

Effects of cyclosporin on joint damage in rheumatoid arthritis. The Italian Rheumatologists Study Group on Rheumatoid Arthritis.

According to the most recent literature, few antirheumatic drugs can claim disease-controlling properties over the anatomical joint damage in rheumatoid arthritis (RA). A small number of studies have favored one or another of the available agents, in particular parenteral gold salts, sulphasalazine and methotrexate, but the evidence regarding their efficacy is not convincing when analysed using methodological criteria known to be important in evaluating radiologic evidence of joint damage. The radiologic results in long-standing RA patients have shown that CsA may be of benefit in reducing disease progression. Data from the second year of a clinical trial designed to compare the disease-controlling, anti-rheumatic properties of CsA with those of conventional disease-modifying anti-rheumatic drugs (DMARDs) in early RA support the hypothesis that CsA may be useful in delaying the appearance of new joint erosion.

Relationship of soluble interleukin-2-receptor and interleukin-6 with class-specific rheumatoid factors during low-dose methotrexate treatment in rheumatoid arthritis.

We studied the effect of a 6-month treatment with low-dose MTX in 22 RA patients, with the purpose of investigating the relationship of sIL-2R and IL-6 serum changes with those of class specific RFs. The patients with RA had higher serum levels of sIL-2R (p < 0.0001), and IL-6 (p < 0.0005) than healthy volunteers. We found that the levels of IgM-RF (p < 0.0004), IgA-RF (p < 0.002), IgG-RF (p < 0.025), sIL-2R (p < 0.017) and IL-6 (p < 0.044) as well as the main clinical and laboratory variables, were significantly reduced in RA patients treated with low dose MTX for six months. The changes from baseline of IgM-RF correlated with those of IL-6 (p < 0.023), suggesting that MTX may affect IL-6 and IgM-RF production in part by a common mechanism. In conclusion our results show that there is a relationship between IL-6 and IgM-RF changes from baseline during MTX therapy, but the hypothesis of a link between the effects of this drug on cytokine network and RF production needs further investigation.

Life-table analysis of cyclosporin A treatment in psoriatic arthritis: comparison with other disease-modifying antirheumatic drugs.

OBJECTIVES: The aim of this study was to determine the cumulative probability of taking CsA in comparison to other DMARDs, as well as the reason for discontinuation of each DMARD, in a large cohort of PsA patients. METHODS: We prospectively studied 172 consecutive patients with a diagnosis of PsA who had been admitted to our rheumatological unit since 1984. We collected information about treatment with DMARDs including: number, dose, duration and causes of withdrawal, including side effects or inefficacy. Cumulative survival analysis was performed by the Kaplan-Meier test and the differences between these survival curves were determined by the Mantel-Hanszel test. RESULTS: The probability curve of continuing to take CsA was significantly lower than that of MTX (p < 0.046). The rate of adverse effects responsible for stopping DMARD therapy was higher in the CsA group, especially with respect to the antimalarial group (p < 0.014). The most common cause of CsA withdrawal was hypertension. The rate of withdrawal due to inefficacy in the CsA group was not significantly different from those observed in the other groups. Nevertheless, the total frequency of discontinuation due to toxicity and inefficacy in the MTX group was significantly lower compared to the gold salts (p < 0.05) and CsA groups (p < 0.01). CONCLUSION: Life-table analysis suggests that PsA patients taking CsA are less likely than patients on MTX to continue long term treatment. Therefore CsA, which seems to be less safe than the antimalarials, could be considered a useful drug in the treatment of PsA, but does seem to represent the drug of first choice, particularly when compared to MTX.

Interleukin-6 and soluble interleukin-2-receptor in psoriatic arthritis: correlations with clinical and laboratory parameters.

OBJECTIVE: In this study we evaluated the relationships of IL-6 and sIL-2R levels with the main clinical and laboratory parameters in PsA patients with peripheral polyarthritis. METHODS: Serum levels of IL-6 and sIL-2R were measured by an enzyme immunoassay kit in patients with peripheral (< 4 joints) PsA (n = 47), with RA (n = 41), or with psoriasis (N = 15) and in healthy volunteers (n = 15) RESULTS: The patients with PsA had higher serum levels of IL-6 and sIL-2R than healthy volunteers and psoriatic patients, while they showed lower levels of IL-6 and sIL-2R than RA patients. We found abnormal values for IL-6 and sIL-2R in 63.8% and 57.4% of PsA patients, respectively. IL-6 levels correlated with the number of painful and swollen joints, RAI, physician's assessment, CRP and ESR, while sIL-2R levels correlated only with the number of swollen joints, the physician's assessment and ESR. IL-6 and sIL-2R correlated with each other. CONCLUSION: Our study shows that IL-6 and sIL-2R may play a role in the pathogenetic mechanism of psoriatic arthritis.

Interleukin-6 and soluble interleukin-2 receptor in juvenile chronic arthritis: correlations with clinical and laboratory parameters.

We sought to determine whether levels of interleukin-6 and soluble interleukin-2 receptor were correlated with clinical parameters including functional capacity indices such as Steinbrocker's class and the Juvenile Arthritis Functional Assessment Report (JAFAR) score, with tests for inflammation, and/or with immunological parameters in 24 patients with active polyarticular or pauciarticular juvenile chronic arthritis. Levels of interleukin-6 and soluble interleukin-2 receptor were significantly higher in juvenile chronic arthritis patients than in healthy controls (p < 0.005 and p < 0.00005, respectively). Interleukin-6 levels were correlated with the following parameters: number of painful joints (p < 0.025); Ritchie's index (p < 0.025); visual analog scale pain score (p < 0.025); Steinbrocker's class (p < 0.025); JAFAR score determined by patients (p < 0.05); JAFAR score determined by parents (p < 0.05); erythrocyte sedimentation rate (p < 0.0002); and serum levels of C-reactive protein (p < 0.0003), hemoglobin (p < 0.05), albumin (p < 0.025), and alpha 2-globulins (p < 0.025). Levels of soluble interleukin-2 receptor did not correlate with any of the parameters studied. Levels of interleukin-6 and soluble interleukin-2 receptor were not correlated with each other. Abnormal levels of interleukin-6 or soluble interleukin-2 receptor were not significantly associated with the presence of antinuclear antibodies, IgM-rheumatoid factor, IgA rheumatoid factor or anticardiolipin antibodies. Our findings suggest that interleukin-6 is a useful parameter for assessing juvenile chronic arthritis and that the potential clinical value of elevated levels of soluble interleukin-2 receptor in this disease needs to be further evaluated in longitudinal studies.

Comparison of ultrasound transmission velocity with computed metacarpal radiogrammetry and dual-photon absorptiometry.

The aim of our study was to evaluate the validity of a quantitative US technique for measuring the bone density of the proximal phalanges of the nondominant hand compared with computed metacarpal radiogrammetry and dual-photon absorptiometry (DPA) of the lumbar spine. Mean US bone velocity (UBV) correlated with mean metacarpal cortical index (MCI), with mean metacarpal bone density (MBD) and with bone mineral density (BMD) of the lumbar spine, whereas it was correlated negatively with age and menopause duration. The average UBV was significantly higher in premenopausal women than in postmenopausal women, and higher in normal lumbar DPA patients than in reduced lumbar DPA patients. We conclude that the US evaluation of the nondominant hand proximal phalanges may be a new alternative way for measuring bone mass in screening of osteoporosis.

Comparison of cyclosporin A and methotrexate in the treatment of psoriatic arthritis: a one-year prospective study.

OBJECTIVE: To compare the effectiveness and toxicity of cyclosporin A (CsA) vs low-dose methotrexate (MTX) over a period of one year in the treatment of psoriatic arthritis (PsA) with peripheral involvement. METHODS: Thirty-five patients with PsA were enrolled in a prospective, controlled, randomized trial. CsA was initially given in doses of 3 mg/kg/day to a maximum permitted dose of 5 mg/kg/day; MTX was given in oral doses of 2.5 mg every 12 hours for 3 consecutive doses each week up to a maximum dose of 15 mg/weekly. Clinical and laboratory evaluations were performed at entry and monthly thereafter. RESULTS: After 6 and 12 months the number of painful joints, the number of swollen joints, the Ritchie index, the duration of morning stiffness, grip strength, CRP, the patient's and the physician's assessment of PsA activity, as well as the PASI, were significantly improved in both treatment groups. ESR values were significantly reduced only in the MTX group (p < 0.01), which also showed a significantly increase of liver enzymes. The changes in the main clinical and laboratory parameters during the course of CsA or MTX treatment were not significantly different except for the AST and ALT levels (p < 0.05). After one year of therapy CsA and MTX were withdrawn in 41.2% and 27.8% of the patients respectively, but these differences were not statistically significant. CONCLUSION: Our one-year prospective trial shows that low-dose CsA and MTX are both effective in the treatment of PsA, but the differences in the tolerability of these drugs must be considered at the start of therapy.