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101.

Background

Linked to extreme rates of chronic heart and kidney disease, pyoderma is endemic amongst Aboriginal children in Australia''s Northern Territory (NT). Many of those with pyoderma will also have scabies. We report the results of a community-based collaboration within the East Arnhem Region, which aimed to reduce the prevalence of both skin infections in Aboriginal children.

Methodology/Principal Findings

Commencing September 2004, we conducted an ecological study that included active surveillance for skin infections amongst children aged <15 years in five remote East Arnhem communities over a three year period. Screening was undertaken by trained local community workers, usually accompanied by another project team member, using a standard data collection form. Skin infections were diagnosed clinically with the aid of a pictorial flip chart developed for the purpose. Topical 5% permethrin was provided for age-eligible children and all household contacts whenever scabies was diagnosed, whilst those with pyoderma were referred to the clinic for treatment in accordance with current guidelines. In addition, annual mass scabies treatment (5% permethrin cream) was offered to all community residents in accordance with current guidelines but was not directly observed. Pyoderma and scabies prevalence per month was determined from 6038 skin assessments conducted on 2329 children. Pyoderma prevalence dropped from 46.7% at baseline to a median of 32.4% (IQR 28.9%–41.0%) during the follow-up period – an absolute reduction of 14.7% (IQR 4.7%–16.8%). Compared to the first 18 months of observation, there was an absolute reduction in pyoderma prevalence of 18 cases per 100 children (95%CI −21.0, −16.1, p≤0.001) over the last 18 months. Treatment uptake increased over the same period (absolute difference 13.4%, 95%CI 3.3, 23.6). While scabies prevalence was unchanged, the prevalence of infected scabies (that is with superimposed pyoderma) decreased from 3.7% (95%CI 2.4, 4.9) to 1.5% (95%CI 0.7, 2.2), a relative reduction of 59%.

Conclusion

Although pyoderma prevalence remained unacceptably high, there was a substantial reduction overall with improvements in treatment uptake a critical factor. More acceptable alternatives, such as cotrimoxazole for pyoderma and ivermectin as a community-wide scabicide, warrant further investigation in these settings. We are encouraged by progress made through this work, where local action was led by local community members and primary health care providers with external training and support.

Trial Registration

ClinicalTrials.gov NCT00884728  相似文献   
102.
103.
Redox modulation is a general mechanism for enzyme regulation, particularly for the post-translational regulation of the Calvin cycle in chloroplasts of green plants. Although red algae and photosynthetic protists that harbor plastids of red algal origin contribute greatly to global carbon fixation, relatively little is known about post-translational regulation of chloroplast enzymes in this important group of photosynthetic eukaryotes. To address this question, we used biochemistry, phylogenetics and analysis of recently completed genome sequences. We studied the functionality of the chloroplast enzymes phosphoribulokinase (PRK, EC 2.7.1.19), NADP-dependent glyceraldehyde 3-phosphate dehydrogenase (NADP-GAPDH, GapA, EC 1.2.1.13), fructose 1,6-bisphosphatase (FBPase, EC 3.1.3.11) and glucose 6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49), as well as NADP-malate dehydrogenase (NADP-MDH, EC 1.1.1.37) in the unicellular red alga Galdieria sulphuraria (Galdieri) Merola. Despite high sequence similarity of G. sulphuraria proteins to those of other photosynthetic organisms, we found a number of distinct differences. Both PRK and GAPDH co-eluted with CP12 in a high molecular weight complex in the presence of oxidized glutathione, although Galdieria CP12 lacks the two cysteines essential for the formation of the N-terminal peptide loop present in higher plants. However, PRK inactivation upon complex formation turned out to be incomplete. G6PDH was redox modulated, but remained in its tetrameric form; FBPase was poorly redox regulated, despite conservation of the two redox-active cysteines. No indication for the presence of plastidic NADP-MDH (and other components of the malate valve) was found.  相似文献   
104.
Mechanisms of Cyclin-Dependent Kinase Inactivation by Progestins   总被引:6,自引:2,他引:6       下载免费PDF全文
The steroid hormone progesterone regulates proliferation and differentiation in the mammary gland and uterus by cell cycle phase-specific actions. In breast cancer cells the predominant effect of synthetic progestins is long-term growth inhibition and arrest in G1 phase. Progestin-mediated growth arrest of T-47D breast cancer cells was preceded by inhibition of cyclin D1-Cdk4, cyclin D3-Cdk4, and cyclin E-Cdk2 kinase activities in vitro and reduced phosphorylation of pRB and p107. This was accompanied by decreases in the expression of cyclins D1, D3, and E, decreased abundance of cyclin D1- and cyclin D3-Cdk4 complexes, increased association of the cyclin-dependent kinase (CDK) inhibitor p27 with the remaining Cdk4 complexes, and changes in the molecular masses and compositions of cyclin E complexes. In control cells cyclin E eluted from Superdex 200 as two peaks of ~120 and ~200 kDa, with the 120-kDa peak displaying greater cyclin E-associated kinase activity. Following progestin treatment, almost all of the cyclin E was in the 200-kDa, low-activity form, which was associated with the CDK inhibitors p21 and p27; this change preceded the inhibition of cell cycle progression. These data suggest preferential formation of this higher-molecular-weight, CDK inhibitor-bound form and a reduced number of cyclin E-Cdk2 complexes as mechanisms for the decreased cyclin E-associated kinase activity following progestin treatment. Ectopic expression of cyclin D1 in progestin-inhibited cells led to the reappearance of the 120-kDa active form of cyclin E-Cdk2 preceding the resumption of cell cycle progression. Thus, decreased cyclin expression and consequent increased CDK inhibitor association are likely to mediate the decreases in CDK activity accompanying progestin-mediated growth inhibition.  相似文献   
105.

Background

Particulate matter (PM) can exacerbate allergic airway diseases. Although health effects of PM with a diameter of less than 100 nm have been focused, few studies have elucidated the correlation between the sizes of particles and aggravation of allergic diseases. We investigated the effects of nano particles with a diameter of 14 nm or 56 nm on antigen-related airway inflammation.

Methods

ICR mice were divided into six experimental groups. Vehicle, two sizes of carbon nano particles, ovalbumin (OVA), and OVA + nano particles were administered intratracheally. Cellular profile of bronchoalveolar lavage (BAL) fluid, lung histology, expression of cytokines, chemokines, and 8-hydroxy-2'-deoxyguanosine (8-OHdG), and immunoglobulin production were studied.

Results

Nano particles with a diameter of 14 nm or 56 nm aggravated antigen-related airway inflammation characterized by infiltration of eosinophils, neutrophils, and mononuclear cells, and by an increase in the number of goblet cells in the bronchial epithelium. Nano particles with antigen increased protein levels of interleukin (IL)-5, IL-6, and IL-13, eotaxin, macrophage chemoattractant protein (MCP)-1, and regulated on activation and normal T cells expressed and secreted (RANTES) in the lung as compared with antigen alone. The formation of 8-OHdG, a proper marker of oxidative stress, was moderately induced by nano particles or antigen alone, and was markedly enhanced by antigen plus nano particles as compared with nano particles or antigen alone. The aggravation was more prominent with 14 nm of nano particles than with 56 nm of particles in overall trend. Particles with a diameter of 14 nm exhibited adjuvant activity for total IgE and antigen-specific IgG1 and IgE.

Conclusion

Nano particles can aggravate antigen-related airway inflammation and immunoglobulin production, which is more prominent with smaller particles. The enhancement may be mediated, at least partly, by the increased local expression of IL-5 and eotaxin, and also by the modulated expression of IL-13, RANTES, MCP-1, and IL-6.  相似文献   
106.
Several analogs of 2,3-diaryl pyrroles were synthesized and evaluated as inhibitors of Eimeria tenella cGMP-dependent protein kinase and in in vivo anticoccidial assays. A 4-fluorophenyl group enhances both in vitro and in vivo activities. The most potent analogs are the 5-(N-methyl, N-ethyl, and N-methylazetidine methyl) piperidyl derivatives 12, 23, and 34. These compounds have a broad spectrum of activity. Based on the in vivo efficacy and cost of synthesis, the N-ethyl analog 23 was chosen as a novel anticoccidial agent for a field trial.  相似文献   
107.
Instantaneous scan sampling for mean distance and synchronous action patterns and all-occurrence sampling for unison call, dance, strut, and hoover-up behaviors were conducted for five potential whooping crane pairs at Patuxent Environmental Science Center, Laurel, Maryland. Dance, strut, and hoover-up differed among pairs, as did total frequency of social behaviors. It was unclear whether or not total frequency of social behaviors during pair formation can be used as an index for potential breeding success. The relative importance of different action patterns should be used as indices of pair compatibility in captive whooping cranes. © 1995 Wiley-Liss, Inc.  相似文献   
108.
109.
A number of xenobiotics are toxic because they rcdox cycle and generate free radicals. Interaction with iron, either to produce reactive species such as the hydroxyl radical, or to promote lipid peroxidation, is an important factor in this toxicity. A potential biological source of iron is ferritin. The cytotoxic pyrimidines, dialuric acid, divicine and isouramil, readily release iron from ferritin and promote ferritin-dependent lipid peroxidation. Superoxide dismutase and GSH, which maintain the pyrimidines in their reduced form, enhance both iron release and lipid peroxidation. Microsomes plus NADPH can reduce a number of iron complexes, although not ferritin. Reduction of Adriamycin. paraquat or various quinones to their radicals by the microsomes enhances reduction of the iron complexes, and in some cases, enables iron release from ferritin. Adriamycin stimulates iron-dependent lipid peroxidation of the microsomes. Ferritin can provide the iron, and peroxidation is most pronounced at low PO2. Compiexing agents that supress intraccllular iron reduction and lipid peroxidation may protect against the toxicity of Adriamycin.  相似文献   
110.
Cysticercosis and echinococcosis cause illness and productivity losses in human and agricultural animal populations. Recent studies suggest that these diseases have large societal impacts on endemic areas. Estimates of burden provide essential, evidence-based data for conducting cost-benefit and cost-utility analyses that will secure political will, and financial and technical resources. To evaluate the burden, the monetary and non-monetary impacts of these zoonoses on human health, agriculture and society must be considered comprehensively. In this article, we review the framework used to assess the burden of cysticercosis and echinococcosis, and the data needed to estimate the extent of the problem for societies.  相似文献   
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