131 research outputs found

    Selective apoptosis of pluripotent mouse and human stem cells by novel ceramide analogues prevents teratoma formation and enriches for neural precursors in ES cell–derived neural transplants

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    The formation of stem cell–derived tumors (teratomas) is observed when engrafting undifferentiated embryonic stem (ES) cells, embryoid body–derived cells (EBCs), or mammalian embryos and is a significant obstacle to stem cell therapy. We show that in tumors formed after engraftment of EBCs into mouse brain, expression of the pluripotency marker Oct-4 colocalized with that of prostate apoptosis response-4 (PAR-4), a protein mediating ceramide-induced apoptosis during neural differentiation of ES cells. We tested the ability of the novel ceramide analogue N-oleoyl serinol (S18) to eliminate mouse and human Oct-4(+)/PAR-4(+) cells and to increase the proportion of nestin(+) neuroprogenitors in EBC-derived cell cultures and grafts. S18-treated EBCs persisted in the hippocampal area and showed neuronal lineage differentiation as indicated by the expression of β-tubulin III. However, untreated cells formed numerous teratomas that contained derivatives of endoderm, mesoderm, and ectoderm. Our results show for the first time that ceramide-induced apoptosis eliminates residual, pluripotent EBCs, prevents teratoma formation, and enriches the EBCs for cells that undergo neural differentiation after transplantation

    Regulation of cell death in mitotic neural progenitor cells by asymmetric distribution of prostate apoptosis response 4 (PAR-4) and simultaneous elevation of endogenous ceramide

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    Cell death and survival of neural progenitor (NP) cells are determined by signals that are largely unknown. We have analyzed pro-apoptotic signaling in individual NP cells that have been derived from mouse embryonic stem cells. NP formation was concomitant with elevated apoptosis and increased expression of ceramide and prostate apoptosis response 4 (PAR-4). Morpholino oligonucleotide-mediated antisense knockdown of PAR-4 or inhibition of ceramide biosynthesis reduced stem cell apoptosis, whereas PAR-4 overexpression and treatment with ceramide analogs elevated apoptosis. Apoptotic cells also stained for proliferating cell nuclear antigen (a nuclear mitosis marker protein), but not for nestin (a marker for NP cells). In mitotic cells, asymmetric distribution of PAR-4 and nestin resulted in one nestin(−)/PAR-4(+) daughter cell, in which ceramide elevation induced apoptosis. The other cell was nestin(+), but PAR-4(−), and was not apoptotic. Asymmetric distribution of PAR-4 and simultaneous elevation of endogenous ceramide provides a possible mechanism underlying asymmetric differentiation and apoptosis of neuronal stem cells in the developing brain

    HLA-DR and HLA-DQ alleles in patients from the south of Brazil: markers for leprosy susceptibility and resistance

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    <p>Abstract</p> <p>Background</p> <p>Many epidemiological studies have shown that the genetic factors of the host play a role in the variability of clinical response to infection caused by <it>M. leprae</it>. With the purpose of identifying genes of susceptibility, the present study investigated the possible role of HLA-DRB1 and DQA1/DQB1 alleles in susceptibility to leprosy, and whether they account for the heterogeneity in immune responses observed following infection in a Southern Brazilian population.</p> <p>Methods</p> <p>One hundred and sixty-nine leprosy patients and 217 healthy controls were analyzed by polymerase chain reaction amplification and reverse hybridization with sequence-specific oligonucleotide probes and sequence-specific primers(One Lambda<sup>®</sup>, CA, USA).</p> <p>Results</p> <p>There was a positive association of HLA-DRB1*16 (*1601 and *1602) with leprosy <it>per se </it>(7.3% <it>vs</it>. 3.2%, <it>P </it>= 0.01, OR = 2.52, CI = 1.26–5.01), in accord with previous serological studies, which showed DR2 as a marker of leprosy. Although, HLA-DQA1*05 frequency (29.8% <it>vs</it>. 20.9%, <it>P </it>= 0.0424, OR = 1.61, CI = 1.09–2.39) was higher in patients, and HLA-DQA1*02 (3.0% <it>vs</it>. 7.5%, <it>P </it>= 0.0392, OR = 0.39, CI = 0.16 – 0.95) and HLA-DQA1*04 (4.0% <it>vs</it>. 9.1%, <it>P </it>= 0.0314, OR = 0.42, CI = 0.19 – 0.93) frequencies lower, <it>P</it>-values were not significant after the Bonferroni's correction. Furthermore, HLA-DRB1*1601 (9.0% <it>vs</it>. 1.8%; <it>P </it>= 0.0016; OR = 5.81; CI = 2.05–16.46) was associated with susceptibility to borderline leprosy compared to control group, and while HLA-DRB1*08 (11.2% <it>vs</it>. 1.2%; <it>P </it>= 0.0037; OR = 12.00; CI = 1.51 – 95.12) was associated with susceptibility to lepromatous leprosy, when compared to tuberculoid leprosy, DRB1*04 was associated to protection.</p> <p>Conclusion</p> <p>These data confirm the positive association of HLA-DR2 (DRB1*16) with leprosy <it>per se</it>, and the protector effect of DRB1*04 against lepromatous leprosy in Brazilian patients.</p

    Interaction of Municipal Garbage Waste and Local Microorganisms (LOM) of Banana Weevil on Soybean Yield

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    Soybean is the third main food commodity after rice and corn because soybean is a source of protein for Indonesian people. The high use of inorganic fertilizers causes fertile land resources to decrease. The need for soybeans increases with the increase in population. Reduced availability of soybean supply so efforts are needed to increase soybean production. Utilization of municipal waste as an effort to reduce the use of inorganic fertilizers. The study aimed to determine the effect of the interaction between municipal solid waste and local microorganisms on banana weevils on soybean yields. The research was conducted in Tember Village Tompaso District Minahasa Regency from May to October 2021. The study used a completely randomized factorial design. The treatment consists of, Factor I (A) = city waste compost. A0=without municipal waste compost, A1=10 tonnes/ha municipal waste compost, A2=20 tonnes/ha municipal waste compost. Factor II (B) = dosage of banana weevil local microorganisms. B0=without local microorganisms; B1= 50 ml of banana weevil local microorganisms/1 liter of water; B2=100 ml of banana weevil local microorganisms/1 liter of water, B3= 150 ml of banana weevil local microorganisms/1 liter of water. Each treatment was repeated three times to obtain 36 trial pots. The results showed that the concentration of 150 ml of local microorganisms (LOM) on banana weevil at 20 tonnes/ha of municipal waste compost increased the number of soybean seeds by 532 and the weight of soybean seeds per plant was 107 grams

    Use of performance feedback to increase healthcare worker hand-hygiene behaviour

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    We will present some (formal) arguments that any Feynman diagram can be understood as a particular case of a Horn-type multivariable hypergeometric function. The advantages and disadvantages of this type of approach to the evaluation of Feynman diagrams is discussed

    Pengaruh Konsentrasi Biourine Untuk Meningkatkan Pertumbuhan Tanaman Kedelai (Glycine max (L.) Merill)

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    The purpose of the research was to study the effect of biourine on soybean plant growth, and to obtain the concentration of biourine that can increase soybean growth. To achieve the objectives, the research was designed using a completely randomized design.&nbsp; The treatments consisted of, A = No Biourine, B = 100 ml biourine/1 liter of water, C = 200 ml biourine/1 liter of water.&nbsp; Each treatment was repeated four times resulting in 12 experimental pots. The parameters observed were the number of leaves and the number of soybean branches.&nbsp; Data were analyzed using analysis of variance and 5% BNT test. The results showed that the application of biourine increased the growth of soybean plants as indicated by plant height and the number of leaves with three branches. The concentration of 100 ml biourine/1 liter of water increased the growth of soybean plants

    Stressors agents in workplace and sugestions to soften its: opinions of the post graduation's nurses

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    A sobrecarga de trabalho, relacionamento e comunicação, características da Instituição e poluição ambiental foram os agentes estressores organizacionais mais citados neste estudo composto por 30 enfermeiras, sendo que a melhoria no planejamento do trabalho, o aspecto de humanização, adequação dos recursos humanos, melhora na comunicação e educação continuada, dentre outras, foram as sugestões identificadas para melhorar estes agentes estressores. Como agentes estressores extra organizacionais, os mais citados foram problemas econômicos e familiares e distância do trabalho / transporte.The work overload, relationship and comunication problems, institution's characteristics and ambiental pollution were the stressing organization agents with the greatest pontuation in this study composed by 30 nurses. The work planning, work humanization, suitable human resourses, improving comunication and continued education were the suggestions given by nurses to minimize these stressing organizational agents. Analysing the stressing extra organizational agents, economic and familiar problems, work distance and transportation to work , were the most pointed

    Dansyl Fluorophore Functionalized Hierarchically Structured Mesoporous Silica Nanoparticles As Novel Latent Fingerprint Development Agents

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    A nanostructured hybrid material based on mesoporous silica nanoparticles (MCM-41) functionalized with chitosan and a fluorescent dye (dansylglycine), designated MCM-41@Ch@DnsGly, was synthesized and characterized with a view to its application for the visualization of latent fingerprints. These nanoparticles were applied as latent fingerprint developers for marks on surfaces of diverse chemical composition, topography, optical characteristics, and spatially variant nature, typical of forensically challenging evidence. For quality assessment of the enhanced fingermarks, the developed images were analyzed holistically using the UK Home Office scale, forensic protocols and, in terms of their constituent features (minutiae), using forensic software. Across a substantive collection of marks deposited on chemically diverse surfaces and subject to complex environmental and temporal histories, 94% of the enhanced images presented sufficient minutiae for comparison with model dactyloscopy images. This novel nanomaterial presents enhanced performance with significant promise for superior exploitation by forensic practitioners in the acquisition and analysis of crime scene evidence
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