A Randomized Open-Label Trial of Artesunate- Sulfadoxine-Pyrimethamine with or without Primaquine for Elimination of Sub-Microscopic P. falciparum Parasitaemia and Gametocyte Carriage in Eastern Sudan

In areas of seasonal malaria transmission, treatment of asymptomatic carriers of malaria parasites, whose parasitaemia persists at low densities throughout the dry season, could be a useful strategy for malaria control. We carried out a randomized trial to compare two drug regimens for clearance of parasitaemia in order to identify the optimum regimen for use in mass drug administration in the dry season.A two-arm open-label randomized controlled trial was conducted during the dry season in an area of distinct seasonal malaria in two villages in Gedarif State in eastern Sudan. Participants were asymptomatic adults and children aged over 6 months, with low-density P. falciparum infection detected by PCR. Participants were randomized to receive artesunate/sulfadoxine-pyrimethamine (AS+SP) combination for three days with or without a dose of primaquine (PQ) on the fourth day. Parasitaemia detected by PCR on days 3, 7 and 14 after the start of treatment and gametocytes detected by RT-PCR on days 7 and 14 were then recorded. 104 individuals who had low density parasitaemia at screening were randomized and treated during the dry season. On day 7, 8.3% were positive by PCR in the AS+SP+PQ group and 6.5% in the AS+SP group (risk difference 1.8%, 95%CI -10.3% to +13.8%). At enrolment, 12% (12/100) were carrying gametocytes. This was reduced to 6.4% and 4.4% by day 14 (Risk difference 1.9% (95%CI -9.3% to +13.2%) in AS+SP+PQ and AS+SP groups, respectively.Addition of primaquine to artemisinin combination treatment did not improve elimination of parasitaemia and prevention of gametocyte carriage in carriers with low-density parasitaemia in the dry season.ClinicalTrials.gov NCT00330902

Campylobacter Infection as a Trigger for Guillain-Barré Syndrome in Egypt

BACKGROUND: Most studies of Campylobacter infection triggering Guillain-Barré Syndrome (GBS) are conducted in western nations were Campylobacter infection and immunity is relatively rare. In this study, we explored Campylobacter infections, Campylobacter serotypes, autoantibodies to gangliosides, and GBS in Egypt, a country where Campylobacter exposure is common. METHODS: GBS cases (n = 133) were compared to age- and hospital-matched patient controls (n = 374). A nerve conduction study was performed on cases and a clinical history, serum sample, and stool specimen obtained for all subjects. RESULTS: Most (63.3%) cases were demyelinating type; median age four years. Cases were more likely than controls to have diarrhea (29.5% vs. 22.5%, Adjusted Odds Ratio (ORa) = 1.69, P = 0.03), to have higher geometric mean IgM anti-Campylobacter antibody titers (8.18 vs. 7.25 P<0.001), and to produce antiganglioside antibodies (e.g., anti-Gd1a, 35.3 vs. 11.5, ORa = 4.39, P<0.0001). Of 26 Penner:Lior Campylobacter serotypes isolated, only one (41:27, C. jejuni, P = 0.02) was associated with GBS. CONCLUSIONS: Unlike results from western nations, data suggested that GBS cases were primarily in the young and cases and many controls had a history of infection to a variety of Campylobacter serotypes. Still, the higher rates of diarrhea and greater antibody production against Campylobacter and gangliosides in GBS patients were consistent with findings from western countries

The Effects Of Cemented Carbide Binder Composition On Tool Wear Encountered In Surfacing Green Lumber

This paper is a summary of work carried out over the past ten years on the wear of cemented carbides during cutting of green wood (Appalachian oak). Experimental evidence is presented showing that tool wear occurs through the preferential removal of the binder through chemical attack by extractives (tannic acid) in the wood followed by mechanical removal of tungsten carbide grains. This occurs when the remaining bond strength between the grains and the binder is no longer sufficient to withstand the action of the shear forces arising from relative motion between the cutting tool, work-piece, and chip. A theoretical model of the wear process based on this evidence is given. Experimental results are presented showing the wear of various cemented carbides under both laboratory (simulated) and actual (field) cutting conditions. The improvement in performance associated with the modification of the composition of the binder predicted from the analysis and measured through (simulated) wear tests agreed well with actual (field) test data. Specifically, a fivefold increase in tool life was obtained through substitution of a chromium/cobalt binder for a standard 6% cobalt binder

On tool wear and its effect on machined surface integrity

This paper presents the results of an investigation of induced residual stress, induced strain, and induced subsurface energy in machined surfaces due to the machining process. The influence of tool wear on residual stress, strain, and energy is also reported. The exact elasticity solution for a split ring was extended and used to calculate the residual stress in the machined surface by using ring dimension changes caused by the electrochemical removal of a thin layer of residually stressed surface. The strain distribution beneath the machined surface was determined by using the grid technique. The subsurface energy stored in the machined surface was then obtained from the data of residual stress and strain. For the materials studied, this investigation showed that such energy could not be neglected when establishing the total energy needed for machining a unit volume of material. Tool coatings having different surface roughness and tools having various magnitudes of flank wear were investigated. The experimental results show that tool wear is a dominant factor affecting the values of induced residual stress, strain, subsurface energy, and the quality of the machined surface. The increase of tool wear caused an increase of residual stress and strain beneath the machined surface. It was also found that the overall energy stored in the machined subsurface increases as the tool wear increases and as the tool surface gets rougher. When the cutting tool is severely worn, the machined surface not only becomes very rough, but also contains many partially fractured laps or cracks. This makes tool wear a key factor in controlling the quality of the machined surface. © 1990 Springer-Verlag New York Inc

Modulation of doxorubicin cytotoxicity by resveratrol in a human breast cancer cell line

<p>Abstract</p> <p>Background</p> <p>Breast cancer is the most common cancer in the Arab world and it ranked first among Saudi females. Doxorubicin (DOX), an anthracycline antibiotic is one of the most effective anticancer agents used to treat breast cancer. chronic cardiotoxicity is a major limiting factor of the use of doxorubicin. Therefore, our study was designed to assess the role of a natural product resveratrol (RSVL) on sensitization of human breast cancer cells (MCF-7) to the action of DOX in an attempt to minimize doxorubicin effective dose and thereby its side effects.</p> <p>Methods</p> <p>Human breast cancer cell line MCF-7, was used in this study. Cytotoxic activity of DOX was determined using (sulforhodamine) SRB method. Apoptotic cells were quantified after treatment by annexin V-FITC- propidium iodide (PI) double staining using flow-cytometer. Cell cycle disturbance and doxorubicin uptake were determined after RSVL or DOX treatment.</p> <p>Results</p> <p>Treatment of MCF-7 cells with 15 μg/ml RSVL either simultaneously or 24 h before DOX increased the cytotoxicity of DOX, with IC50 were 0.056 and 0.035 μg/ml, respectively compared to DOX alone IC50 (0.417 μg/ml). Moreover, flow cytometric analysis of the MCF-7 cells treated simultaneously with DOX (0.5 μg/ml) and RSVL showed enhanced arrest of the cells in G₀ (80%). On the other hand, when RSVL is given 24 h before DOX although there was more increased in the cytotoxic effect of DOX against the growth of the cells, however, there was decreased in percentage arrest of cells in G₀, less inhibition of DOX-induced apoptosis and reduced DOX cellular uptake into the cells.</p> <p>Conclusion</p> <p>RSVL treatment increased the cytotoxic activity of DOX against the growth of human breast cancer cells when given either simultaneously or 24 h before DOX.</p

Antioxidant and Anti-Inflammatory Potential of Thymoquinone and Lycopene Mitigate the Chlorpyrifos-Induced Toxic Neuropathy

CPF (chlorpyrifos) is an organophosphate pesticide used in agricultural and veterinary applications. Our experiment aimed to explore the effects of thymoquinone (TQ) and/or lycopene (LP) against CPF-induced neurotoxicity. Wistar rats were categorized into seven groups: first group served as a control (corn oil only); second group, TQ (10 mg/kg); third group, LP (10 mg/kg); fourth group, CPF (10 mg/kg) and deemed as CPF toxic control; fifth group, TQ + CPF; sixth group, (LP + CPF); and seventh group, (TQ + LP + CPF). CPF intoxication inhibited acetylcholinesterase (AchE), decreased glutathione (GSH) content, and increased levels of malondialdehyde (MDA), an oxidative stress biomarker. Furthermore, CPF impaired the activity of antioxidant enzymes including superoxide dismutase (SOD) and catalase (CAT) along with enhancement of the level of inflammatory mediators such as tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β. CPF evoked apoptosis in brain tissue. TQ or LP treatment of CPF-intoxicated rats greatly improved AchE activity, oxidative state, inflammatory responses, and cell death. Co-administration of TQ and LP showed better restoration than their sole treatment. In conclusion, TQ or LP supplementation may alleviate CPF-induced neuronal injury, most likely due to TQ or LPs’ antioxidant, anti-inflammatory, and anti-apoptotic effects