16 research outputs found

    Zebularine induces long-term survival of pancreatic islet allotransplants in streptozotocin treated diabetic rats.

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    Coping with the immune rejection of allotransplants or autologous cells in patients with an active sensitization towards their autoantigens and autoimmunity presently necessitates life-long immune suppressive therapy acting on the immune system as a whole, which makes the patients vulnerable to infections and increases their risk of developing cancer. New technologies to induce antigen selective long-lasting immunosuppression or immune tolerance are therefore much needed

    Mörka Neuron och Mobiltelefoner : Dedicerad till en 90-årig man, Arne Brun i Lund

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    Med denna svenska översikt av våra egna och andra forskares observationer av mörka neuron vid mikrovågs exponering från mobiltelefoner, som lite senkommet tillägnas Arne Brun på hans 90 års-dag, vill vi att hans insatser blir uppmärksammade och inte faller i glömska.Kring 2000 millennium skiftet pågick ett intensivt arbete i Lund med att sammanfatta och bekräfta effekterna av exponering med GSM-900 MHz mikrovågor på blod-hjärna barriären och hjärnans neuroner. Leif G. Salford, Arne Brun och medarbetare presenterade år 2003 i tidskriften Environmental Health Perspectives resultaten från en undersökning av skador på nervcellerna i råtthjärna efter exponering för mikrovågor från GSM Mobiltelefoner. Kontroller och testdjur visade alla tecken på närvao av albumin i hypotalamus, vilket år normalt och indikerar att albumin infärgningen av BBB läckaget också fungerar. Cresylviolettfärgningen avslöjade förekomst av spridda och grupperade mörka nervceller, som ofta var skrumpna och mörkt homogent färgade utan urskiljbara interna cellstrukturer. Några av dessa mörka nervceller var också albuminpositiva eller visade cytoplasmatiska mikrovakuoler som indikerar en aktiv patologisk process. År 2008 presenterades resultaten av ytterligare undersökningar av blod-hjärn barriärens permeabilitet och nervcellsskador i råtthjärnan efter en återhämtningstid på antingen 14 och 28 dagar efter 2 timmas exponering för mikrovågor från GSM-mobiltelefoner i 900 MHz-bandet. Efter 14 dagars återhämtningstid observerades albumin-läckage i BBB och albumin upptag i neuroner. Mörka neuron observerades endast hos råttor som exponerats med det lägsta SAR-värdet, 0,12 mW/kg. Efter 28 dagars återhämtnings period observerades läckage av albumin endast hos råttor som exponerats med det högsta SAR-värdet, 100 mW/kg. Däremot observerades efter 28 dagar förekomst av mörka neuron i råtthjärnor hos alla grupperna vilket korrelerade väl med neuronernas albumin upptag.I studien observeras neuro-patologiska förändringar redan vid SAR-värden så låga som 0,12 mW/kg vilket överensstämmer med våra tidigare resultat. Speciellt iögonfallande är att det högsta albumin upptaget i neuroner observeras vid den lägsta SAR nivån på 0,12 mW/kg. Frekvensen hos förekomsten av mörka nervceller ökade, jämfört med kontrollerna både efter 14 och 28 dagars återhämtning, men var endast signifikant vid 28 dagar efter exponering. Inga signifikanta tecken på förekomsten av mörka neuron observerades emellertid efter 7 dagars återhämtning.I en Fransk studie redovisad av Poulletier de Gannes och medarbetare 2009 exponerades enbart huvudet hos 16 st. Fischer 344-råttor (14 veckor gamla) för GSM-900 under 2 timmar vid SAR värden 0,14 och 2,0 W/kg. Fjorton alternatvt 50 dagar efter GSM-900 exponeringen kunde varken BBB-läckage eller förekomst av mörka nervceller upptäckas i rått hjärnorna. Deras resultat indikerar att det föreligger en väsentlig skillnad i resultaten vid helkropp exponering jämfört med exponering av endast huvudet.År 2015 presenterades en studie, stödd av Nationella Vetenskaps Akademin i Kina (NSFC), avseende albumin-läckage i blod-hjärnbarriären efter exponering med kontinuerliga mikrovågor på 900 MHz med SARvärden mellan 0,016 (hela kroppen) och 2 W/kg (lokalt i huvudet). Hos råttor som exponerats under 28 dagar observerades cellulärt ödem och neuronal cellorganell degeneration hos råttorna. Dessutom observerades med immun-färgning BBB-läckage av albumin i hippocampus och cortex. Efter exponering för 900 MHz mikrovågor under 14 respektive 28 dagar hade serum albumin diffunderat in i neuropilen mellan cellkropparna, som omger neuronerna. Upptag av Albumin i hippocampus neuron hos råttor exponerade under 28 dagar, visar förekomst av mörka neuron. Deras resultat är i linje med Lunda-resultaten som publicerades 2003 och 2008

    Nonthermal GSM RF and ELF EMF effects upon rat BBB permeability

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    Since the late 1980s, our group has examined the effects of radiofrequency electromagnetic fields (RF-EMF), including pulse-modulated waves of the type emitted by mobile phones, upon the blood-brain barrier. In more than 2,000 rats, we have repeatedly demonstrated a passage of the rats' own albumin from the blood through the brain capillaries into the surrounding brain parenchyma at SAR values down to 0.1mW/kg. In most of these experiments, the animals were exposed in TEM-cells, ventilated by an external electrical fan at 50 Hz. In the present study, we examined whether the extremely low frequency (ELF) magnetic fields from the fan (50 Hz, 0.3-1.5 μT) might add to the RF effect. Sixty-four rats were divided into 4 groups: RF only, ELF only and RF + ELF exposure plus a sham group. The GSM-900 MHz RF exposure was at the very low, nonthermal, average whole-body SAR level 0.4 mW/kg. Demonstration of the normally occurring albumin extravasation in the basal hypothalamus is our inbuilt control proving that the staining is reliable. Two full series of staining of the whole material gave negative results for hypothalamus. Not until we changed to avidin, biotin, and antibodies from a third supplier, we received an acceptable staining. Twenty-five percent of the RF animals had a pathological albumin leakage, while the ELF and RF + ELF groups with three and two pathological findings, respectively, were not significantly different from the control group. We conclude that the use of external fans has had no major influence upon the result

    A Story of Immunization with Autologous IFN-γ Secreting Glioma Cells in Patients with Glioblastoma Multiforme is Safe and Prolongs Both Overall and Progress Free Survival

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    The study was a non-randomized controlled phase I-II trial to study were to ascertain the safety, feasibility and efficacy of immunotherapy with autologous IFN-γ transfected tumour cells in patients with glioblastoma multiforme. Autologous tumour cells harvested during surgery were cultured and transduced with the human IFN-γ gene. Irradiated cells were administered as intradermal immunizations every third week. Endpoints for safety were records of toxicity and adverse events, for feasibility the per cent of treated patients out of eligible patients and time to treatment and for clinical efficacy overall survival (OS) and progress free survival (PFS). Eight eligible patients, between 50 and 69 years, were immunized between 8 and 14 times after treatment with surgery and radiotherapy without adverse events or toxicity. Neurological status and quality of life were unchanged during immunotherapy. The immunized patients had a significantly (p < 0.05) longer median overall survival (488 days, 16.1 months than a matched control group of nine patients treated with only surgery and radiotherapy (271 days, 9.0 months). The prolongation of survival was also significant compared to all GBM treated at the same institution during the same period and published control groups within the same age cohort

    Photon activation therapy of RG2 glioma carrying Fischer rats using stable thallium and monochromatic synchrotron radiation.

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    75 RG2 glioma-carrying Fischer rats were treated by photon activation therapy (PAT) with monochromatic synchrotron radiation and stable thallium. Three groups were treated with thallium in combination with radiation at different energy; immediately below and above the thallium K-edge, and at 50 keV. Three control groups were given irradiation only, thallium only, or no treatment at all. For animals receiving thallium in combination with radiation to 15 Gy at 50 keV, the median survival time was 30 days, which was 67% longer than for the untreated controls (p = 0.0020) and 36% longer than for the group treated with radiation alone (not significant). Treatment with thallium and radiation at the higher energy levels were not effective at the given absorbed dose and thallium concentration. In the groups treated at 50 keV and above the K-edge, several animals exhibited extensive and sometimes contra-lateral edema, neuronal death and frank tissue necrosis. No such marked changes were seen in the other groups. The results were discussed with reference to Monte Carlo calculated electron energy spectra and dose enhancement factors

    No viable transplant in control animal.

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    <p>Control animal which became diabetic at day 14 after transplantation, where no insulin positive cells are seen within the thickened renal capsule (C) (semiquantitative scoring of 0). Bar is 80 µm.</p

    In: Abstracts from the World Federation of Neuro-Oncology Second Quadrennial Meeting and the Sixth Meeting of the European Association for Neuro-Oncology: May 5–8, 2005, Edinburgh, UK. No.308

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    Abstracts from Neuro-Oncology are provided here courtesy of Society for Neuro-Oncology and Duke University Press.Adjuvant chemotherapy using DNA-damaging agents has largely failed to make a significant impact on the outcome of patients with malignant astrocytoma. One of the primary mechanisms of resistance to nitrosureas such as CCNU is mediated through O6-methylguanine-DNA methyltrans-ferase (MGMT). This DNA repair enzyme removes the cytotoxic alkyl adducts from O6-guanine, and hence the level of MGMT activity in tumor cells is related to their sensitivity to nitroureas. It has been proposed that functional inactivation of MGMT through hypermethylation of the gene promotor region could be predictive of chemosensitivity. We have previously reported differential sensitivity to CCNU in a panel of 17 short-term cultures derived from malignant astrocytoma. In this study, we determined the methylation status of MGMT using methylation-specific PCR in these 17 cultures. We also assessed the amounts of MGMT mRNA and protein present in each culture using real-time quantitative PCR and immunohistochemistry with a commercial antibody against MGMT. There was good correlation between MGMT promotor methylation and presence of MGMT mRNA and protein in all but 2 cases. In both these cultures, mRNA and protein were not detected even though the MGMT promotor was unmethylated. However, there was no correlation between sensitivity to CCNU and MGMT status. In the 2 most resistant cultures, the MGMT gene was methylated and was not expressed. Similarly, in 4/5 of the most sensitive cultures, MGMT was unmethylated, and in 2 of these cases, there was commensurate MGMT expression. However, in the remaining 2 cultures, MGMT expression was not detected, indicating that an alternative mechanism to gene methylation is responsible for MGMT inactivation. This study highlights that the resistance of malignant astrocytoma to nitroureas may be more complex than simple reliance on MGMT activity and prediction of response to such agents by MGMT methylation status should be used with caution

    Expression of IDO1 in rat spleen.

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    <p>Analysis of the IDO1-gene expression in spleens from four Wistar rats treated with daily i.p. injections of Zebularine (225 mg/kg/day, two rats) or PBS (two rats) for 7 days. IDO1 expression was measured by Real-time qPCR fluorescence and the normalized rIDO1 expression level for each spleen sample calculated by rIDO1 expression divided by rHPRT expression. The normalized IDO1 expressions of spleens from Zebularine-treated rats are presented in relation to the mean of that of PBS-treated controls.</p
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