106 research outputs found
Neuroinflammation and structural injury of the fetal ovine brain following intra-amniotic Candida albicans exposure.
BackgroundIntra-amniotic Candida albicans (C. Albicans) infection is associated with preterm birth and high morbidity and mortality rates. Survivors are prone to adverse neurodevelopmental outcomes. The mechanisms leading to these adverse neonatal brain outcomes remain largely unknown. To better understand the mechanisms underlying C. albicans-induced fetal brain injury, we studied immunological responses and structural changes of the fetal brain in a well-established translational ovine model of intra-amniotic C. albicans infection. In addition, we tested whether these potential adverse outcomes of the fetal brain were improved in utero by antifungal treatment with fluconazole.MethodsPregnant ewes received an intra-amniotic injection of 10(7) colony-forming units C. albicans or saline (controls) at 3 or 5 days before preterm delivery at 0.8 of gestation (term ~ 150 days). Fetal intra-amniotic/intra-peritoneal injections of fluconazole or saline (controls) were administered 2 days after C. albicans exposure. Post mortem analyses for fungal burden, peripheral immune activation, neuroinflammation, and white matter/neuronal injury were performed to determine the effects of intra-amniotic C. albicans and fluconazole treatment.ResultsIntra-amniotic exposure to C. albicans caused a severe systemic inflammatory response, illustrated by a robust increase of plasma interleukin-6 concentrations. Cerebrospinal fluid cultures were positive for C. albicans in the majority of the 3-day C. albicans-exposed animals whereas no positive cultures were present in the 5-day C. albicans-exposed and fluconazole-treated animals. Although C. albicans was not detected in the brain parenchyma, a neuroinflammatory response in the hippocampus and white matter was seen which was characterized by increased microglial and astrocyte activation. These neuroinflammatory changes were accompanied by structural white matter injury. Intra-amniotic fluconazole reduced fetal mortality but did not attenuate neuroinflammation and white matter injury.ConclusionsIntra-amniotic C. albicans exposure provoked acute systemic and neuroinflammatory responses with concomitant white matter injury. Fluconazole treatment prevented systemic inflammation without attenuating cerebral inflammation and injury
In vivo biofunctional evaluation of hydrogels for disc regeneration
Purpose Regenerative strategies aim to restore the original
biofunctionality of the intervertebral disc. Different
biomaterials are available, which might support disc
regeneration. In the present study, the prospects of success
of two hydrogels functionalized with anti-angiogenic peptides
and seeded with bone marrow derived mononuclear
cells (BMC), respectively, were investigated in an ovine
nucleotomy model.
Methods In a one-step procedure iliac crest aspirates
were harvested and, subsequently, separated BMC were
seeded on hydrogels and implanted into the ovine disc. For
the cell-seeded approach a hyaluronic acid-based hydrogel
was used. The anti-angiogenic potential of newly developed
VEGF-blockers was investigated on ionically crosslinked
metacrylated gellan gum hydrogels. Untreated discs
served as nucleotomy controls. 24 adult merino sheep were
used. After 6 weeks histological, after 12 weeks histological
and biomechanical analyses were conducted.
Results Biomechanical tests revealed no differences
between any of the implanted and nucleotomized discs. All
implanted discs significantly degenerated compared to
intact discs. In contrast, there was no marked difference
between implanted and nucleotomized discs. In tendency,
albeit not significant, degeneration score and disc height
index deteriorated for all but not for the cell-seeded
hydrogels from 6 to 12 weeks. Cell-seeded hydrogels
slightly decelerated degeneration.
Conclusions None of the hydrogel configurations was
able to regenerate biofunctionality of the intervertebral
disc. This might presumably be caused by hydrogel
extrusion. Great importance should be given to the development
of annulus sealants, which effectively exploit the
potential of (cell-seeded) hydrogels for biological disc
regeneration and restoration of intervertebral disc
functioningThis work was supported by the EU-project Disc Regeneration (NMP3-LA-2008-213904). Technical assistance of Iris Baum and the whole animal surgery team of the Institute of Orthopaedic Research and Biomechanics, Ulm, are gratefully acknowledged. DDAHA hydrogels were kindly provided by Cristina Longinotti (DDAHA, Anika Therapeutics, Abano Therme, Italy)
Hormone-sensing cells require Wip1 for paracrine stimulation in normal and premalignant mammary epithelium
10.1186/bcr3381Breast Cancer Research15
Mesenchymal Stem Cells Induce T-Cell Tolerance and Protect the Preterm Brain after Global Hypoxia-Ischemia
Hypoxic-ischemic encephalopathy (HIE) in preterm infants is a severe disease for which no curative treatment is available. Cerebral inflammation and invasion of activated peripheral immune cells have been shown to play a pivotal role in the etiology of white matter injury, which is the clinical hallmark of HIE in preterm infants. The objective of this study was to assess the neuroprotective and anti-inflammatory effects of intravenously delivered mesenchymal stem cells (MSC) in an ovine model of HIE. In this translational animal model, global hypoxia-ischemia (HI) was induced in instrumented preterm sheep by transient umbilical cord occlusion, which closely mimics the clinical insult. Intravenous administration of 2 x 106MSC/kg reduced microglial proliferation, diminished loss of oligodendrocytes and reduced demyelination, as determined by histology and Diffusion Tensor Imaging (DTI), in the preterm brain after global HI. These anti-inflammatory and neuroprotective effects of MSC were paralleled by reduced electrographic seizure activity in the ischemic preterm brain. Furthermore, we showed that MSC induced persistent peripheral T-cell tolerance in vivo and reduced invasion of T-cells into the preterm brain following global HI. These findings show in a preclinical animal model that intravenously administered MSC reduced cerebral inflammation, protected against white matter injury and established functional improvement in the preterm brain following global HI. Moreover, we provide evidence that induction of T-cell tolerance by MSC might play an important role in the neuroprotective effects of MSC in HIE. This is the first study to describe a marked neuroprotective effect of MSC in a translational animal model of HIE
Anastrozole versus tamoxifen for the prevention of locoregional and contralateral breast cancer in postmenopausal women with locally excised ductal carcinoma in situ (IBIS-II DCIS): A double-blind, randomised controlled trial
Cellulose nanofiber backboned Prussian blue nanoparticles as powerful adsorbents for the selective elimination of radioactive cesium
On 11 March 2011, the day of the unforgettable disaster of the 9 magnitude Tohoku earthquake and quickly followed by the devastating Tsunami, a damageable amount of radionuclides had dispersed from the Fukushima Daiichi’s damaged nuclear reactors. Decontamination of the dispersed radionuclides from seawater and soil, due to the huge amounts of coexisting ions with competitive functionalities, has been the topmost difficulty. Ferric hexacyanoferrate, also known as Prussian blue (PB), has been the most powerful material for selectively trapping the radioactive cesium ions; its high tendency to form stable colloids in water, however, has made PB to be impossible for the open-field radioactive cesium decontamination applications. A nano/nano combinatorial approach, as is described in this study, has provided an ultimate solution to this intrinsic colloid formation difficulty of PB. Cellulose nanofibers (CNF) were used to immobilize PB via the creation of CNF-backboned PB. The CNF-backboned PB (CNF/PB) was found to be highly tolerant to water and moreover, it gave a 139 mg/g capability and a million (106) order of magnitude distribution coefficient (Kd) for absorbing of the radioactive cesium ion. Field studies on soil and seawater decontaminations in Fukushima gave satisfactory results, demonstrating high capabilities of CNF/PB for practical applications.National Science Foundation (U.S.) (DMR-1507806
Over-the-Counter Monocyclic Non-Steroidal Anti-Inflammatory Drugs in Environment—Sources, Risks, Biodegradation
Recently, the increased use of monocyclic
non-steroidal anti-inflammatory drugs has resulted in
their presence in the environment. This may have
potential negative effects on living organisms. The
biotransformation mechanisms of monocyclic nonsteroidal
anti-inflammatory drugs in the human body
and in other mammals occur by hydroxylation and
conjugation with glycine or glucuronic acid.
Biotransformation/biodegradation of monocyclic
non-steroidal anti-inflammatory drugs in the environment
may be caused by fungal or bacterial microorganisms.
Salicylic acid derivatives are degraded by
catechol or gentisate as intermediates which are
cleaved by dioxygenases. The key intermediate of
the paracetamol degradation pathways is hydroquinone.
Sometimes, after hydrolysis of this drug, 4-
aminophenol is formed, which is a dead-end metabolite.
Ibuprofen is metabolized by hydroxylation or
activation with CoA, resulting in the formation of
isobutylocatechol. The aim of this work is to attempt
to summarize the knowledge about environmental risk
connected with the presence of over-the-counter antiinflammatory
drugs, their sources and the biotransformation
and/or biodegradation pathways of these
drugs
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