1,493 research outputs found

    Controlled synthesis and characterization of hollow flower-like silver nanostructures

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    Kamel AM Eid, Hassan ME AzzazyNovel Diagnostics and Therapeutics Group, Yousef Jameel Science and Technology Research Center, School of Sciences and Engineering, The American University in Cairo, New Cairo, EgyptBackground: The synthesis of anisotropic silver nanoparticles is a time-consuming process and involves the use of expensive toxic chemicals and specialized laboratory equipment. The presence of toxic chemicals in the prepared anisotropic silver nanostructures hindered their medical application. The authors have developed a fast and inexpensive method for the synthesis of three-dimensional hollow flower-like silver nanostructures without the use of toxic chemicals.Methods: In this method, silver nitrate was reduced using dextrose in presence of trisodium citrate as a capping agent. Sodium hydroxide was added to enhance reduction efficacy of dextrose and reduce time of synthesis. The effects of all four agents on the shape and size of silver nanostructures were investigated.Results: Robust hollow flower-like silver nanostructures were successfully synthesized and ranged in size from 0.2 µm to 5.0 µm with surface area between 25–240 m2/g. Changing the concentration of silver nitrate, dextrose, sodium hydroxide, and trisodium citrate affected the size and shape of the synthesized structures, while changing temperature had no effect.Conclusion: The proposed method is simple, safe, and allows controlled synthesis of anisotropic silver nanostructures, which may represent promising tools as effective antimicrobial agents and for in vitro diagnostics. The synthesized hollow nanostructures may be used for enhanced drug encapsulation and sustained release.Keywords: silver nanoparticles, 3D hollow, flower-like, green synthesi

    Pyloric atresia epidermolysis bullosa aplasia cutis syndrome: a case report and literature review

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    The association between epidermolysis bullosa and congenital pyloric atresia is rare, but is a known distinct clinical entity with autosomal recessive inheritance. We report on a case of a baby girl born by cesarean section at 37 weeks’ gestation to a G7 P7 mother and weighed 2.84 kg. At birth, there was denuded skin over the right leg from the knee joint up to the middle of the right foot. Abdominal radiograph was thus performed and indicated absent gas in the small bowel and single bubble appearance of the stomach. Pyloric atresia was surgically corrected. Electron microscopy of skin biopsies showed junctional epidermolysis bullosa. There was typical nail dystrophy and no corneal lesions; ultrasonography for the renal system was normal. At 4 months of age, the baby required gastrostomy and fundoplication for severe failure to thrive. Six weeks after her second surgical procedure, the patient presented to the emergency room dead; the parents provided a typical scenario of sudden infant death syndrome at home. Examination indicated no signs of child abuse; the parents refused an autopsy exam for the child.Keywords: aplasia cutis syndrome, epidermolysis bullosa, pyloric atresi

    Isolation and Characterization of Palmitic Acid from Ethyl Acetate Extract of Root Bark of Terminalia Glaucescens

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    The aim of this study is to identify and characterized the bioactive compounds from the root bark of the plant. Preliminary phytochemical screening of the root bark extract of Terminalia glaucescens revealed the presence of steroids, terpenoids, saponins, flavonoids, tannins and cardiac glycoside. The plant has wide folk medicinal use in traditional medicine. The air dried root bark was pulverized to powder, subjected to hot extraction (soxhlet) with methanol, and fractionated into n-hexane, ethyl acetate, and n-butanol fractions. Ethyl acetate as bioactive fraction based on sensitivity test was subjected to TLC and column chromatography. The isolated compound was colourless powder, which was further subjected to IR, UV, 13CNMR and 1HNMR for proper characterization and elucidation of the structure. The compound was concluded as palmitic acid

    Genotypic and phenotypic patterns of antimicrobial susceptibility of Helicobacter pylori strains among Egyptian patients

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    Helicobacter pylori (H. pylori) is currently recognized as one of the most common chronic bacterial infections worldwide. Eradication of bacteria is effective in healing peptic ulcers, preventing ulcer relapses, and potentially decreasing the risk of progression to gastric carcinoma. For successful eradication of bacteria, it is imperative that the clinician be aware of the current antimicrobial susceptibility profiles of isolates within the region. Therefore, the aim of this study is to compare the phenotypic and genotypic patterns of antibiotics’ susceptibility to H. pylori strains among Egyptian patients. 60 symptomatic cases were enrolled. H. pylori infection was diagnosed by upper endoscopy as well as biopsy. Antimicrobial susceptibility to H. pylori strains was assessed in all subjects by disc diffusion and Ellipsometer testing (E-testing) methods. Further molecular characterization of gene

    Binding to CSA receptor is associated with asymptomatic and mild malaria: a preliminary study using P.falciparum field isolates from Sudan

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    Malaria imposes great socio-economic burden on humanity, and afflicts approximately 90 countries and territories in the tropical and subtropical regions, almost one half of them are in Africa, South of Sahara. Sequestration of parasitized erythrocytes within the small vessels of vital organs is a key event in the pathogenesis of malaria and responsible of virulence of Plasmodium falciparum parasite. To find out whether the ability of infected red blood cells (IRBCs) to adhere to a specific receptor is a risk factor for developing severe clinical manifestation of the disease, in-vitro cytoadhesion and inhibition experiments were performed on field isolates obtained from five symptomatic and five asymptomatic patients inhabiting Gazira State, Central Sudan. The results showed significant lower levels (

    Infiltrating ductal carcinoma breast with central necrosis closely mimicking ductal carcinoma in situ (comedo type): a case series

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    Here we present a series of infiltrative ductal carcinoma breast cases (infiltrative ductal carcinoma with central necrosis) so closely mimicking \u27DCIS with central comedo necrosis\u27 that on initial morphological analysis these foci of tumors were labeled as DCIS (high grade, comedo). However on further histological work up and by using immunohistochemistry (IHC) for myoepithelial markers it was later confirmed that these were foci of infiltrative ductal carcinoma breast with central necrosis. This case series gives the realization that a breast carcinoma may be partly or entirely DCIS like yet invasive. In such a dilemma IHC especially for assessment of myoepithelial lining is very useful to differentiate DCIS comedo from invasive carcinoma with central necrosis

    Twelve Tips for Medical Students starting Clinical Placements in the United Kingdom

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    Transitioning from the pre-clinical to clinical years at medical school can be challenging and overwhelming. This paper aims to utilise the experience of healthcare professionals to provide tips for medical students to consider in order to maximise their learning opportunities. Before starting a placement, it is highly encouraged that you familiarise yourself with the curriculum, remember to bring your essentials and dress appropriately. During your placement, ensure good attendance keeping, introduce yourself to the team, manage your time well, engage in self-directed learning, ask questions to other doctors, interact with allied health care professionals and follow the patient’s journey from admission to discharge. It is also key to be wary of university requirements, regularly practice history-taking and clinical examination and examination style questions. Prioritise a suitable work-life balance by enjoying hobbies and extra-curricular activities in order to avoid burn-out. These tips should ensure medical students make the most of their clinical placements as well as making it a memorable and enjoyable experience

    A possible role for Phlebotomus (Anaphlebotomus) rodhaini (Parrot, 1930) in transmission of Leishmania donovani

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    <p>Abstract</p> <p>Background</p> <p>Visceral leishmaniasis (VL, kala azar), caused by <it>Leishmania donovani </it>is a major health problem in Sudan and other East African countries. In this region the only proven vectors of <it>L. donovani </it>are <it>Phlebotomus orientalis </it>in eastern Sudan, Ethiopia and Upper Nile areas of Southern Sudan and <it>Phlebotomus martini </it>in Ethiopia, Kenya and Southern Sudan. In this report, we present the first evidence that <it>Phlebotomus rodhaini </it>may also play a role in maintaining transmission of <it>L. donovani </it>between animal reservoir hosts in eastern Sudan. The study was conducted in a zoonotic focus of visceral leishmaniasis in Dinder National Park, eastern Sudan, where previous work showed high infection rates of <it>L. donovani </it>in <it>P. orientalis</it>. Sand flies, captured by CDC traps were dissected and examined for infection with <it>Leishmania </it>parasites. Parasite isolates were subjected to <it>L. donovani </it>specific PCR. Field experiments were also carried out to compare efficiency of rodent baited and un-baited CDC traps in collection of <it>P. rodhaini </it>and determine its man-biting rate.</p> <p>Results</p> <p>Three female <it>P. rodhain</it>i were found infected with <it>Leishmania </it>parasites in an astonishingly small number of flies captured in three separate field trips. Two of these isolates were typed by molecular methods as <it>L. donovani</it>, while the third isolate was inoculated into a hamster that was subsequently lost. Although <it>P. rodhaini is </it>generally considered a rare species, results obtained in this study indicate that it can readily be captured by rodent-baited traps. Results of human landing collection showed that it rarely bites humans in the area.</p> <p>Conclusion</p> <p>It is concluded that <it>P. rodhaini </it>is a possible vector of <it>L. donovani </it>between animal reservoir hosts but is not responsible for infecting humans. It is suggested that the role of <it>P</it>. <it>rodhaini </it>in transmission of <it>L. donovani </it>in other zoonotic foci of visceral leishmaniasis in Africa should be re-examined.</p

    Characterization of human mesothelin transcripts in ovarian and pancreatic cancer

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    BACKGROUND: Mesothelin is an attractive target for cancer immunotherapy due to its restricted expression in normal tissues and high level expression in several tumor types including ovarian and pancreatic adenocarcinomas. Three mesothelin transcript variants have been reported, but their relative expression in normal tissues and tumors has been poorly characterized. The goal of the present study was to clarify which mesothelin transcript variants are commonly expressed in human tumors. METHODS: Human genomic and EST nucleotide sequences in the public databases were used to evaluate sequences reported for the three mesothelin transcript variants in silico. Subsequently, RNA samples from normal ovary, ovarian and pancreatic carcinoma cell lines, and primary ovarian tumors were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and nucleotide sequencing to directly identify expressed transcripts. RESULTS: In silico comparisons of genomic DNA sequences with available EST sequences supported expression of mesothelin transcript variants 1 and 3, but there were no sequence matches for transcript variant 2. Newly-derived nucleotide sequences of RT-PCR products from tissues and cell lines corresponded to mesothelin transcript variant 1. Mesothelin transcript variant 2 was not detected. Transcript variant 3 was observed as a small percentage of total mesothelin amplification products from all studied cell lines and tissues. Fractionation of nuclear and cytoplasmic RNA indicated that variant 3 was present primarily in the nuclear fraction. Thus, mesothelin transcript variant 3 may represent incompletely processed hnRNA. CONCLUSION: Mesothelin transcript variant 1 represents the predominant mature mRNA species expressed by both normal and tumor cells. This conclusion should be important for future development of cancer immunotherapies, diagnostic tests, and gene microarray studies targeting mesothelin
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