The Toxicity of Selected Trace Metals to Lecane inermis Rotifers Isolated from Activated Sludge

The aim of the study was to assess the toxicity of a range of trace metals to the rotifer Lecane inermis, a species tested as a potential biological tool to control activated sludge bulking caused by overgrowth of filamentous bacteria in wastewater treatment plants. LC50 values (concentration lethal to 50 % of individuals, mg dm^?3) were ranked in the following order: Cu < Al < Fe < Zn < Sn < Mn. L. inermis apparently is more sensitive to metals than other aquatic species widely used as model organisms in ecotoxicological testing, making it potentially useful for quick ecotoxicological tests.     

Reactive oxygen species–mediated killing of activated fibroblasts by arsenic trioxide ameliorates fibrosis in a murine model of systemic sclerosis

Objective

In patients with systemic sclerosis (SSc), activated fibroblasts produce reactive oxygen species (ROS) that stimulate their proliferation and collagen synthesis. By analogy with tumor cells that undergo apoptosis upon cytotoxic treatment that increases ROS levels beyond a lethal threshold, we tested whether activated fibroblasts could be selectively killed by the cytotoxic molecule arsenic trioxide (As₂O₃) in a murine model of SSc.

Methods

SSc was induced in BALB/c mice by daily intradermal injections of HOCl. Mice were simultaneously treated with daily intraperitoneal injections of As₂O₃.

Results

As₂O₃ limited dermal thickness and inhibited collagen deposition, as assessed by histologic examination and measurement of mouse skin and lung collagen contents. As₂O₃ abrogated vascular damage, as shown by serum vascular cell adhesion molecule 1 level, and inhibited the production of autoantibodies, interleukin‐4 (IL‐4), and IL‐13 by activated T cells. These beneficial effects were mediated through ROS generation that selectively killed activated fibroblasts containing low levels of glutathione.

Conclusion

Our findings indicate that treatment with As₂O₃ dramatically improves skin and lung fibrosis in a mouse model of SSc, providing a rationale for the evaluation of As₂O₃ treatment in patients with SSc.

     

Dietary and socio-economic factors in relation to Helicobacter pylori re-infection

AIM： To examine if dietary and socio-economic factors contribute to Helicobacter pylori （H pylori） re-infection. METHODS： The population of patients consisted of subjects in whom Hpylori infection had been successfully treated in the past. Patients were divided into two groups： Ⅰ-examined group （111 persons with Hpylori re-infection） and Ⅱ-control group （175 persons who had not been re-infected）. The respondents were interviewed retrospectively on their dietary habits and socio-economic factors. RESULTS： A statistically significant lower frequency of fermented dairy products （P 〈 0.0001）, vegetables （P = 0.02）, and fruit （P = 0.008） consumption was noted among patients with Hpylori re-infection as compared to those who had not been re-infected. CONCLUSION： High dietary intake of probiotic bacteria, mainly Lactobacillus, and antioxidants, mainly vitamin C （contained in fruit and vegetables）, might decrease the risk of Hpylori re-infection.     

Growth retardation and delayed puberty in children and adolescents with juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common joint disorder in developing children. Juvenile idiopathic arthritis is difficult to diagnose and treat. In some patients, signs and symptoms can be frustratingly inconsistent, contradictory or idiosyncratic. Short stature in patients with JIA is usually due to reduced growth in the lower extremities, and only rarely due to reduced growth in the spinal column. In some studies, children with JIA were found to have infantile body proportions. Puberty is delayed in children with JIA. In children with chronic arthritic disorders, there is a strong correlation between the activity of the disease and the age of puberty. The main goals in reducing growth retardation in children with JIA are promoting timely remission and reducing the duration and dosage of corticosteroid treatment. It is important to regularly monitor physical development. Further improvements to the treatment protocol depend on continued interdisciplinary research involving paediatricians, rheumatologists and clinical anthropologists.     

Are single nucleotide polymorphisms of the immunoglobulin A Fc receptor gene associated with allergic asthma?

BACKGROUND: Eosinophils are important components of allergic inflammation. The immunoglobulin A (IgA) Fc receptor (FcalphaRI), encoded by the FCAR gene, is a possible candidate for eosinophil activation at mucosal surfaces, where IgA is abundant. Both elevated cell surface expression of FcalphaRI and increased avidity for IgA were described on eosinophils from allergic subjects. The aim of our study was to examine the possible association of FCAR gene polymorphisms with allergic asthma. METHODS: We screened three regions of the FCAR gene: (1) the promoter region, (2) exon 3, encoding the first extracellular domain (EC1), and (3) exon 5, coding for the transmembrane and cytoplasmic domain, for new and published polymorphisms using a sensitive temperature gradient gel electrophoresis technique and compared their frequencies in 112 patients diagnosed with allergic asthma and 100 healthy controls. RESULTS: Six polymorphisms, including two novel ones, were detected. No differences between patients and controls were found in the distribution of any of these polymorphisms. CONCLUSION: FcalphaRI polymorphism does not seem to be a risk factor in allergic asthma. Nevertheless, this is the first report on the distribution of 6 single nucleotide polymorphisms of the FCAR gene in a human population and the first study on FCAR polymorphism in allergic asthma.     

Gene for the activating natural killer cell receptor, KIR2DS1, is associated with susceptibility to psoriasis vulgaris

Psoriasis vulgaris, particularly its juvenile form, is strongly associated with the HLA-Cw*06 allele encoding the HLA-Cw6 molecule. This molecule is recognized by the inhibitory receptor KIR2DL1 and the activatory receptor KIR2DS1, which are expressed on natural killer cells and subpopulations of T lymphocytes. Humans differ by the presence or absence of particular KIR genes. We hypothesized that either activatory KIR2DS1 or inhibitory KIR2DL1 gene frequencies might be different in psoriatic patients from a control population. Therefore, we compared the frequencies of KIR2D inhibitory (L) and activatory (S) genes in 116 psoriasis vulgaris patients and in 123 healthy controls. Fourteen novel gene combinations were found. KIR2DS1 was present in 85% of the patients, but only in 51% of the controls (corrected p [pc] < 0.0009). Similarly, HLA-Cw*06 was much more frequent in patients (77%) than in controls (17%; pc < 0.00002). Statistical analysis suggests that, although the contribution of these two factors to psoriasis is partially independent, they interact nevertheless. This result strongly speaks for a role of KIR2DS1 on recognition of HLA-Cw6 in susceptibility to psoriasis.     

Extracting the barbs from complement assays: Identification and optimisation of a safe substitute for traditional buffers

Complement assays have for many years utilised buffers based on barbitone (veronal) despite the well-recognised toxicity of this agent and the tight regulations on its use in most countries. The use of barbitone in complement assay buffers is steeped in history, from a time when no other suitable buffers were available. This is no longer the case, encouraging us to explore alternatives to barbitone for complement assays. We compared a simple, non-toxic HEPES buffer with commercially sourced complement fixation test diluent (CFD), the “gold standard” barbitone buffer, in several clinically relevant complement activity assays and across species.In classical pathway haemolysis assays in human and non-human serum, there was no difference in haemolytic curves or calculated haemolytic activity (CH50) between CFD and an optimised HEPES buffer (HBS) supplemented with cations. Alternative pathway haemolysis assays in human serum were also identical in the two buffers. In a complement fixation test for anti-erythrocyte antibodies, complement consumption was identical for the two buffer systems.The data demonstrate that barbitone-based buffers are unnecessary for assays of complement activity and can readily be replaced with safe and simple alternatives.     

Rodzaje i wskazania do stałej stymulacji serca u dzieci

The permanent cardiac pacing in children constitutes an important challenge for paediatric cardiologist and for surgeons performing implantation procedures. This task involves not only a necessity for establishing indications but also a need for a specific selection of the pacing leads and pacemaker, and the implantation technique. The number of paediatric patients who need a pacemaker implantation is increasing, including not only patients with congenital atrioventricular conduction disorders and fewer cases of sick sinus syndrome but also the patients after congenital heart diseases surgery. The main concept in electrotherapy in children remains the same as in adults: the prevention of a significant symptomatic bradycardia as well as the provision of an undisturbed physical growth and intellectual development. A physician responsible for therapeutic decision-making should be aware of life-long consequences in this age group, where pacing will be continued usually for several decades.     

When the outcome is different than expected: Subjective expectancy shapes reward prediction error at the FRN level

Converging evidence in human electrophysiology suggests that evaluative feedback provided during performance monitoring (PM) elicits two distinctive and successive ERP components: the feedback‐related negativity (FRN) and the P3b. Whereas the FRN has previously been linked to reward prediction error (RPE), the P3b has been conceived as reflecting motivational or attentional processes following the early processing of the RPE, including action value updating. However, it remains unclear whether these two consecutive neurophysiological effects depend on the direction of the unexpectedness (better‐ or worse‐than‐expected outcomes; signed RPE) or instead only on the degree of unexpectedness irrespective of direction (i.e., unsigned RPE). To address this question, we devised an experiment in which we manipulated the objective reward probability and the subjective reward expectancy (via instructions) in a factorial within‐subject design and explored amplitude changes of the FRN and the P3b. A 64‐channel EEG was recorded while 32 participants performed a speeded go/no‐go task in which evaluative feedback based on the reward probability either violated expectancy (thereby creating a RPE) or did not. This violation corresponded either to better‐ or worse‐than‐expected events. Results showed that the FRN was larger when RPE occurred than when it did not, but irrespective of the direction of this violation. Interestingly, in these two conditions, action value was updated for the positive feedback selectively, as shown by the P3b amplitude. These results obey a two‐stage model of PM assuming that unsigned RPE is first rapidly detected (FRN level) before the positive feedback’s value is updated selectively (P3b effect).