Publications by authors named "Landauer M"

There are no FDA-approved drugs that can be administered prior to ionizing radiation exposure to prevent hematopoietic-acute radiation syndrome (H-ARS). A suspension of synthetic genistein nanoparticles was previously shown to be an effective radioprotectant against H-ARS when administered prior to exposure to a lethal dose of total body radiation. Here we aimed to determine the time to protection and the duration of protection when the genistein nanosuspension was administered by intramuscular injection, and we also investigated the drug's mechanism of action.

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Early assessment and intervention are crucial to alleviate symptoms and prevent long-term negative outcomes in children suffering from Attention-deficit/hyperactivity disorder (ADHD). In Germany, at present, no standardized screening for ADHD is routinely administered. This study aims to evaluate a potential screening measure in a study population that is representative for a primary school entrance exam population in a German metropolitan region.

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Several infrastructure projects are under development or already operational across the Arctic region. Often the deployment of such projects creates benefits at the national, regional, or global scales. However, local communities can experience negative impacts due to the requirements for extensive land areas, which cause pressure on traditional land use.

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17β-Estradiol is known to regulate energy metabolism and body weight. Ovariectomy results in body weight gain while estradiol administration results in a reversal of weight gain. Isoflavones, found in rodent chow, can mimic estrogenic effects making it crucial to understand the role of these compounds on metabolic regulation.

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Accidental high-dose radiation exposures can lead to multi-organ injuries, including radiation dermatitis. The types of cellular damage leading to radiation dermatitis are not completely understood. To identify the cellular mechanisms that underlie radiation-induced skin injury in vivo, we evaluated the time-course of cellular effects of radiation (14, 16 or 17 Gy X-rays; 0.

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Article Synopsis
  • Phytoestrogens, particularly isoflavones found in rodent diets, mimic estrogen and can disrupt endocrine functions by influencing estrogen receptors.
  • In ovariectomized (OVX) rats, the presence of isoflavones altered the effects of 17β-estradiol (E2), showing that E2 caused anxiety when isoflavones were included, but reduced anxiety when they weren't.
  • Additionally, E2 promoted antidepressant-like behaviors and increased BDNF expression in the hippocampus, amygdala, and hypothalamus only when isoflavones were part of the diet, highlighting their role in modulating hormonal effects on behavior.
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Damage to normal lung tissue is a limiting factor when ionizing radiation is used in clinical applications. In addition, radiation pneumonitis and fibrosis are a major cause of mortality following accidental radiation exposure in humans. Although clinical symptoms may not develop for months after radiation exposure, immediate events induced by radiation are believed to generate molecular and cellular cascades that proceed during a clinical latent period.

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We reported that microRNA-30c (miR-30c) plays a key role in radiation-induced human cell damage through an apoptotic pathway. Herein we further evaluated radiation-induced miR-30 expression and mechanisms of delta-tocotrienol (DT3), a radiation countermeasure candidate, for regulating miR-30 in a mouse model and human hematopoietic CD34+ cells. CD2F1 mice were exposed to 0 (control) or 7-12.

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We recently demonstrated that natural delta-tocotrienol (DT3) significantly enhanced survival in total-body irradiated (TBI) mice, and protected mouse bone marrow cells from radiation-induced damage through Erk activation-associated mTOR survival pathways. Here, we further evaluated the effects and mechanisms of DT3 on survival of radiation-induced mouse acute gastrointestinal syndrome. DT3 (75-100 mg/kg) or vehicle was administered as a single subcutaneous injection to CD2F1 mice 24 h before 10-12 Gy (60)Co total-body irradiation at a dose rate of 0.

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Previous studies demonstrated that genistein protects mice from radiation-induced bone marrow failure. To overcome genistein's extremely low water solubility, a nanoparticle suspension of genistein has been formulated for more rapid dissolution. In the current study, we evaluated the radioprotective effects of a nanoparticle formulation of genistein on survival and hematopoietic recovery in mice exposed to total-body gamma irradiation.

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The hematopoietic system is sensitive to radiation injury, and mortality can occur due to blood cell deficiency and stem cell loss. Genistein and the angiotensin converting enzyme (ACE) inhibitor captopril are two agents shown to protect the hematopoietic system from radiation injury. In this study we examined the combination of genistein with captopril for reduction of radiation-induced mortality from hematopoietic damage and the mechanisms of radiation protection.

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Article Synopsis
  • Captopril, an angiotensin converting enzyme inhibitor, affects erythroid recovery in mice after total body irradiation (TBI), showing improved recovery when given post-irradiation but hindering recovery when administered beforehand.
  • The study measured plasma levels of erythropoietin (EPO) and thrombopoietin (TPO) in C57BL/6 mice, alongside gene expression and activation of hypoxia-inducible factors (HIFs) in response to captopril and TBI.
  • Results indicated that captopril has a complex effect on EPO regulation and HIF activation, suppressing both after TBI but enhancing EPO induction before irradiation, highlighting its role in managing erythroid progen
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Mice are increasingly used to investigate mechanobiology in fracture healing. The need exists for standardized models allowing for adjustment of the mechanical conditions in the fracture gap. We introduced such a model using rigid and flexible external fixators with considerably different stiffness (axial stiffnesses of 18.

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Concern regarding the potential for radiation exposure from accidents or nuclear and radiologic terrorism is increasing. The purpose of this study was to determine whether the addition of minimal supportive care consisting of hydration or nutritional gels could be used to reduce mortality in mice exposed to (60)Co gamma-radiation. Male CD2F1 mice received 0, 8.

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Objective: Angiotensin II (Ang II), a potent vasoconstrictor, affects the growth and development of hematopoietic cells. Mixed findings have been reported for the effects of angiotensin-converting enzyme (ACE) inhibitors on radiation-induced injury to the hematopoietic system. We investigated the consequences of different regimens of the ACE inhibitor captopril on radiation-induced hematopoietic injury.

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Article Synopsis
  • A need exists for effective drugs to reduce injuries from ionizing radiation in both military and civilian settings.
  • Previous research showed that a non-toxic dose of genistein can protect against acute radiation damage by promoting recovery of blood cell progenitors.
  • This study found that genistein treatment enhances the levels of important cytokines, specifically G-CSF and IL-6, which may aid in quicker recovery of blood cells after radiation exposure.
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Purpose: The search for ideal protective agents for use in a variety of radiation scenarios has continued for more than six decades. This review evaluates agents and procedures that have the potential to protect against acute and late effects of ionising radiation when administered either before or after radiation exposure.

Conclusion: Over the years, extensive experimental studies of radiation-protective agents have enhanced our knowledge of radiation physics, chemistry, and biology.

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Purpose: In 2007, a legal reform introduced formal health economic evaluation for selected reimbursement decisions by the statutory health insurance in Germany. The methods of evaluation are currently under discussion. This study assesses whether an approach based on decision-analytic cost per QALY modelling fits with the legal requirements set by Book Five of the German Social Code (SGB V).

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Purpose: In this study we addressed whether genistein-induced radioprotection in mice is associated with alterations of the cell cycle of hematopoietic stem and progenitor cells.

Materials And Methods: C57BL/6J female mice received a single subcutaneous injection of genistein (200 mg/kg) 24 h prior to a lethal dose (7.75 Gy, (60)Co) of total body irradiation.

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The effects of genistein on 30-day survival and delayed lung injury were examined in C57BL/6J female mice. A single subcutaneous injection of vehicle (PEG-400) or genistein (200 mg/kg) was administered 24 h before total body irradiation (7.75 Gy (60)Co, 0.

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Purpose: Genistein, a non-toxic isoflavone from soybeans, has immunomodulating and radioprotective properties. In this study we investigated the mechanism for genistein-induced radioprotection by evaluating the recovery of bone marrow cells and peripheral blood hematology in lethally irradiated mice.

Materials And Methods: CD2F1 male mice received a single subcutaneous injection of genistein (200 mg/kg) 24 h prior to a lethal, total body irradiation dose (8.

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Genistein, a radioprotective soy isoflavone and protein kinase inhibitor, blocks the invasion of pathogenic bacteria in mammalian epithelial cells. The purpose of this study was to evaluate the direct effect of genistein on the survival and growth of the probiotic Lactobacillus reuteri and selected opportunistic bacteria in vitro as a prelude to in vivo use for managing postirradiation sepsis. We evaluated the opportunistic bacterial enteropathogens Escherichia coli, Shigella sonnei, and Staphylococcus aureus as well as Klebsiella pneumoniae and the non-pathogenic organism, Bacillus anthracis (Sterne).

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Article Synopsis
  • The study examined the effects of genistein, an isoflavone, on survival after exposure to lethal gamma radiation in male mice.
  • Mice given genistein 24 hours before radiation showed significantly better survival rates compared to controls, while those treated 1 hour prior did not.
  • Additionally, genistein proved non-toxic at various doses in terms of behavior and physiological health indicators in non-irradiated mice.
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The potential of antioxidants to reduce the cellular damage induced by ionizing radiation has been studied in animal models for more than 50 years. The application of antioxidant radioprotectors to various human exposure situations has not been extensive although it is generally accepted that endogenous antioxidants, such as cellular non-protein thiols and antioxidant enzymes, provide some degree of protection. This review focuses on the radioprotective efficacy of naturally occurring antioxidants, specifically antioxidant nutrients and phytochemicals, and how they might influence various endpoints of radiation damage.

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