318 research outputs found

    Rapid and sensitive methods for detection of Allorhizobium vitis, causal agent of grapevine crown gall

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    A rapid method and sensitive methods for extraction of bacterial DNA from pure culture and directly from plant materiel were compared in polymerase chain reaction with specific primers VCF3/VCR3 to see the reliable method that can used in the detection of tumorigenic strain of Allorhizobium vitis causal agent of grapevine crown gall. From the three tested methods of DNA extraction from pure culture, the alkaline method is the most effective technique for the extraction presenting a high sensitivity with a detection threshold equal to 5.104 CFU/ml. Five different protocols for extracting bacterial DNA from plant tissues of infected tomato, based on the use of an extraction buffer, were tested to see its usefulness in detecting pathogenic strain of A. vitisS4. Two protocols based on the use of Triton X-100 and Tween 20 were efficient for detecting A. vitis S4 directly from tomato tumors with a sensitivity of 103 CFU/ml for the both protocols. Consequently, these protocols were proposed as specific protocols for the detection of tumorigenic strain of A. vitis from symptomatic and asymptomatic plants

    Probing the Water Stability Limits and Degradation Pathways of Metal-Organic Frameworks (MOFs)

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    A comprehensive model to describe the water stability of prototypical metal–organic frameworks (MOFs) is derived by combining different types of theoretical and experimental approaches. The results provide an insight into the early stages of water-triggered destabilization of MOFs and allow detailed pathways to be proposed for the degradation of different MOFs under aqueous conditions. The essential elements of the approach are computing the pKa values of coordinated water molecules and geometry relaxations. Variable-temperature and pH infrared spectroscopy techniques are used to corroborate the main findings. The model developed herein helps to explain stability limits observed for several prototypical MOFs, including MOF-5, HKUST-1, UiO-66, and MIL-101-Cr, in aqueous solutions, and thus, provides an insight into the possible degradation pathways in acidic and basic environments. The formation of a metal hydroxide through the autoprotolysis of metal-coordinated water molecules and the strength of carboxylate–metal interactions are suggested to be two key players that govern stability in basic and acidic media, respectively. The methodology presented herein can effectively guide future efforts, which are especially significant for in silico screening, for developing novel MOFs with enhanced aqueous stability

    Study of CD25 expression on leukemic cells: a prognostic factor in acute myeloid leukemia

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    BackgroundAcute myeloid leukemia (AML) is a heterogeneous hematologic malignancy characterized by a clonal expansion of myeloid blasts. Treatment strategies of patients with AML are based on various prognostic factors, including age and performance status of the patient, as well as cytogenetic and molecular characteristics of the leukemic clone.Our aim was to study the expression of cluster of differentiation (CD)25 in adult Egyptian patients with newly diagnosed AML and to assess its prognostic relevance. MethodsThis study was conducted on 50 newly diagnosed AML patients at the Hematology Unit, Internal Medicine Department, Alexandria Main University Hospital. All patients were subjected to full history taking, thorough clinical examination, and laboratory investigations, including detection of CD25 expression on blast cells by flow cytometry. Conventional karyotyping was done on 11 patients at the time of diagnosis. ResultsIn our study group, 12 patients were positive for CD25 expression, and this positivity was associated with worse overall survival and shorter leukemia-free survival. On evaluating the response to treatment among CD25-positive AML patients with normal karyotype, they had lower complete remission rates and higher relapse and death rates. ConclusionsExpression of CD25 in AML patients at presentation can be considered a poor independent prognostic factor

    Opportunistic Parasites among Immunosuppressed Children in Minia District, Egypt

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    A total of 450 stool samples were collected from inpatient and outpatient clinics of Pediatric Department, Minia University Hospital, Minia District, Egypt. Two groups of patients were studied, including 200 immunosuppressed and 250 immunocompetent children. Stool samples were subjected to wet saline and iodine mounts. A concentration technique (formol-ether sedimentation method) was carried out for stool samples diagnosed negative by wet saline and iodine mounts. Samples were stained by 2 different methods; acid fast stain (modified Ziehl-Neelsen stain) and Giemsa stain. Total 188 cases (94%) were diagnosed positive for parasitic infections among immunosuppressed children, whereas 150 cases (60%) were positive in immunocompetent children (P<0.0001). The most common protozoan infection in immunosuppressed group was Cryptosporidium parvum (60.2%), followed by Blastocystis hominis (12.1%), Isospora belli (9.7%), and Cyclospora caytenensis (7.8%). On the other hand, Entamoeba histolytica (24.6%) and Giardia lamblia (17.6%) were more common than other protozoans in immunocompetent children

    Effect of Using Hybrid Nano-Particles on Physical and Mechanical Properties of Cement Mortar

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    This research evaluates the addition of graphene sheets and hybrid nano-materials (graphene with different nano-materials like nano-silica or nano-clay) on compressive strength, flexural strength and thermal conductivity of cement mortar. Graphene sheets were added in three percentages (0.04%, 0.05%, and 0.06%) and (0.03%, 0.04%, and 0.05%) graphene sheets with 1%nano-silica or with 5% nano-clay by weight of cementitious materials. For all specimens, w/c ratio 0.4was applied. Scanning Electron Microscope and thermal conductivity tests were also performed on the optimum specimens at age 28 days. Results indicated that the optimum dose of graphene sheets was 0.05% by weight where the compressive strength, the flexural strength were improved by 35.66%  and 33.33%  respectively, and low thermal conductivity by 6.36% at age 28 days .No significant increase in compressive and flexural strength on adding  hybrid nano-materials (graphene sheets with 1%nano- silica) to mortar. Also reduction effect in compressive and flexural strengths was achieved on adding hybrid nano-materials (graphene sheets with 5% nano-clay) to mortar.  High thermal conductivity was obtained at age 28 days with respect to control ones when hybrid nano-materials were added to cement mortar

    The cardioprotective effects of secoisolariciresinol diglucoside (flaxseed lignan) against cafeteria diet-induced cardiac fibrosis and vascular injury in rats: an insight into apelin/AMPK/FOXO3a signaling pathways

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    Introduction: Fast food is a major risk factor for atherosclerosis, a leading cause of morbidity and mortality in the Western world. Apelin, the endogenous adipokine, can protect against cardiovascular disease via activating its receptor, APJ. Concurrently, secoisolariciresinol diglucoside (SDG), a flaxseed lignan extract (FLE), showed a therapeutic impact on atherosclerosis. The current study aimed to examine the effect of SDG on cafeteria diet (CAFD)-induced vascular injury and cardiac fibrosis via tracking the involvement of the apelin/APJ pathway.Methods: Thirty male rats were allocated into control, FLE-, CAFD-, CAFD/FLE-, and CAFD/FLE/F13A-treated rats, where F13A is an APJ blocker. All treatments lasted for 12 weeks.Results and discussion: The CAFD-induced cardiovascular injury was evidenced by histological distortions, dyslipidemia, elevated atherogenic indices, cardiac troponin I, collagen percentage, glycogen content, and apoptotic markers. CAFD increased both the gene and protein expression levels of cardiac APJ, apelin, and FOXO3a, in addition to increasing endothelin-1, VCAM1, and plasminogen activator inhibitor-1 serum levels and upregulating cardiac MMP-9 gene expression. Moreover, CAFD reduced serum paraoxonase 1 and nitric oxide levels, cardiac AMPK, and nuclear Nrf2 expression. FLE attenuated CAFD-induced cardiovascular injury. Such effect was reduced in rats receiving the APJ blocker, implicating the involvement of apelin/APJ in FLE protective mechanisms.Conclusion: FLE supplementation abrogated CAFD-induced cardiac injury and endothelial dysfunction in an apelin/APJ-dependent manner

    New perspectives in human stem cell therapeutic research

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    Human stem cells are in evaluation in clinical stem cell trials, primarily as autologous bone marrow studies, autologous and allogenic mesenchymal stem cell trials, and some allogenic neural stem cell transplantation projects. Safety and efficacy are being addressed for a number of disease state applications. There is considerable data supporting safety of bone marrow and mesenchymal stem cell transplants but the efficacy data are variable and of mixed benefit. Mechanisms of action of many of these cells are unknown and this raises the concern of unpredictable results in the future. Nevertheless there is considerable optimism that immune suppression and anti-inflammatory properties of mesenchymal stem cells will be of benefit for many conditions such as graft versus host disease, solid organ transplants and pulmonary fibrosis. Where bone marrow and mesenchymal stem cells are being studied for heart disease, stroke and other neurodegenerative disorders, again progress is mixed and mostly without significant benefit. However, correction of multiple sclerosis, at least in the short term is encouraging. Clinical trials on the use of embryonic stem cell derivatives for spinal injury and macular degeneration are beginning and a raft of other clinical trials can be expected soon, for example, the use of neural stem cells for killing inoperable glioma and embryonic stem cells for regenerating β islet cells for diabetes. The change in attitude to embryonic stem cell research with the incoming Obama administration heralds a new co-operative environment for study and evaluation of stem cell therapies. The Californian stem cell initiative (California Institute for Regenerative Medicine) has engendered global collaboration for this new medicine that will now also be supported by the US Federal Government. The active participation of governments, academia, biotechnology, pharmaceutical companies, and private investment is a powerful consortium for advances in health

    Serum Phosphorus and Risk of Cardiovascular Disease, All-Cause Mortality, or Graft Failure in Kidney Transplant Recipients: An Ancillary Study of the FAVORIT Trial Cohort

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    Mild hyperphosphatemia is a putative risk factor for cardiovascular disease [CVD], loss of kidney function, and mortality. Very limited data are available from sizable multicenter kidney transplant recipient (KTR) cohorts assessing the potential relationships between serum phosphorus levels and the development of CVD outcomes, transplant failure, or all-cause mortality

    Validation of Half-Reaction Volumes of the Promega PowerPlex® Forensic Amplification Kits (PowerPlex® 18D Systems, PowerPlex ® 21System, PowerPlex® Fusion System and PowerPlex® Y23 System) in STR Analysis

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    DNA amplification is known to be the most expensive step during forensic DNA analysis. This study evaluated the half-reaction amplification protocol (12.5 µL PCR product) using DNA amplification kits from Promega PowerPlex® (PowerPlex® 18D System, PowerPlex ®21System, PowerPlex® Fusion System and PowerPlex® Y23 System), which might aid in reducing sample analysis cost by half and allow the analysis of more samples. A sensitivity study (15 samples) along with testing of various blood stain samples (n=100) that were submitted to the Medico-Legal Directorate laboratory for DNA testing was accomplished to compare the DNA profiles resulting from half-reaction volume procedure to those with full-reaction volume procedure, using three differed methods along with standard protocol to evaluate the effect of half reaction volume with some variables. Results demonstrated the use of half-reaction amplification protocol preceded by washing step for all aforementioned DNA amplification kits gave a robust and reliable amplification result that aid to increase the number of samples analyzed and decreased the test cost for each kit without compromising the quality of 3DNA profiles obtained
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