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2.
Mol Imaging Biol ; 21(5): 818-824, 2019 10.
Article in English | MEDLINE | ID: mdl-30617729

ABSTRACT

PURPOSE: To evaluate the ability of anti-1-amino-3-anti-1-amino-3-[18F]fluorocyclobutane-1-carboxylic acid ([18F]fluciclovine) positron emission tomography/X-ray computed tomography (PET/CT) in comparison to Technetium-99m 2-methoxy isobutyl isonitrile ([99mTc]sestamibi) single-photon emission computed tomography/CT (SPECT/CT) for the localization of hyperfunctioning parathyroid glands in patients with hyperparathyroidism. PROCEDURES: Four patients with hyperparathyroidism underwent 60-minutes sequential neck and thorax PET/CT after [18F]fluciclovine (352 ± 28 MBq) injection. Lesion uptake and target-to-background ratios (TBR) were compared with [99mTc]sestamibi (798 ± 27 MBq) SPECT/CT in the same patient. RESULTS: Both techniques detected 4/5 hyperfunctioning parathyroid glands identified at surgery. The highest [18F]fluciclovine uptake and TBRs were at 5-9 min with rapid washout. [99mTc]sestamibi had significantly higher TBRs compared with [18F]fluciclovine (5-9 min) for blood pool (10.9 ± 4.7 vs 1.3 ± 0.6; p < 0.01) and reference muscle backgrounds (5.8 ± 3.0 vs 1.7 ± 0.6; p < 0.01), with non-significant trend for thyroid tissue background (1.3 ± 0.5 vs 1.1 ± 0.5; p = 0.73). CONCLUSION: Hyperfunctioning parathyroid glands can be detected on [18F]fluciclovine PET/CT at early imaging, but conspicuity (TBR) is better with [99mTc]sestamibi. [18F]fluciclovine PET/CT does not seem promising in the detection of hyperfunctioning parathyroid glands.


Subject(s)
Carboxylic Acids/chemistry , Cyclobutanes/chemistry , Parathyroid Glands/diagnostic imaging , Parathyroid Glands/physiopathology , Positron Emission Tomography Computed Tomography , Carboxylic Acids/pharmacokinetics , Cyclobutanes/pharmacokinetics , Feasibility Studies , Female , Humans , Male , Middle Aged , Technetium Tc 99m Sestamibi/pharmacokinetics
3.
Nature ; 563(7733): 661-665, 2018 11.
Article in English | MEDLINE | ID: mdl-30464339

ABSTRACT

One of the hallmarks of quantum physics is the generation of non-classical quantum states and superpositions, which has been demonstrated in several quantum systems, including ions, solid-state qubits and photons. However, only indirect demonstrations of non-classical states have been achieved in mechanical systems, despite the scientific appeal and technical utility of such a capability1,2, including in quantum sensing, computation and communication applications. This is due in part to the highly linear response of most mechanical systems, which makes quantum operations difficult, as well as their characteristically low frequencies, which hinder access to the quantum ground state3-7. Here we demonstrate full quantum control of the mechanical state of a macroscale mechanical resonator. We strongly couple a surface acoustic-wave8 resonator to a superconducting qubit, using the qubit to control and measure quantum states in the mechanical resonator. We generate a non-classical superposition of the zero- and one-phonon Fock states and map this and other states using Wigner tomography9-14. Such precise, programmable quantum control is essential to a range of applications of surface acoustic waves in the quantum limit, including the coupling of disparate quantum systems15,16.

4.
Amino Acids ; 50(9): 1301-1305, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29905905

ABSTRACT

We investigated if previously demonstrated inhibition of fluciclovine (18F) in vitro could be replicated in a PC3-Luc xenograft mouse model. Following intratumoral injection of 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH), alpha-(methylamino)isobutyric acid (MeAIB) or saline, fluciclovine PET tumor-to-background activity was 43.6 (± 5.4)% and 25.3 (± 5.2)% lower in BCH (n = 6) and MeAIB (n = 5) injected PC3 Luc xenografts, respectively, compared to saline-injected controls (n = 2). Partial inhibition of fluciclovine uptake by BCH and MeAIB can be demonstrated in vivo similar to previous in vitro modeling.


Subject(s)
Carboxylic Acids/metabolism , Cyclobutanes/metabolism , Prostatic Neoplasms/metabolism , Animals , Biological Transport , Carboxylic Acids/chemistry , Cell Line, Tumor , Cyclobutanes/chemistry , Heterografts , Humans , Luminescence , Male , Mice , Mice, Nude , Positron Emission Tomography Computed Tomography , Prostate/chemistry , Prostate/metabolism , Prostatic Neoplasms/diagnostic imaging
5.
Phys Rev Lett ; 120(15): 150504, 2018 Apr 13.
Article in English | MEDLINE | ID: mdl-29756860

ABSTRACT

We realize a Λ system in a superconducting circuit, with metastable states exhibiting lifetimes up to 8 ms. We exponentially suppress the tunneling matrix elements involved in spontaneous energy relaxation by creating a "heavy" fluxonium, realized by adding a capacitive shunt to the original circuit design. The device allows for both cavity-assisted and direct fluorescent readouts, as well as state preparation schemes akin to optical pumping. Since direct transitions between the metastable states are strongly suppressed, we utilize Raman transitions for coherent manipulation of the states.

6.
Nat Commun ; 9(1): 172, 2018 01 09.
Article in English | MEDLINE | ID: mdl-29317635

ABSTRACT

In the original version of this Article, the affiliation details for Peter Groszkowski and Jens Koch were incorrectly given as 'Department of Physics, University of Chicago, Chicago, IL, 60637, USA', instead of the correct 'Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA'. This has now been corrected in both the PDF and HTML versions of the Article.

7.
Nat Commun ; 8(1): 1904, 2017 12 04.
Article in English | MEDLINE | ID: mdl-29199271

ABSTRACT

Qubit connectivity is an important property of a quantum processor, with an ideal processor having random access-the ability of arbitrary qubit pairs to interact directly. This a challenge with superconducting circuits, as state-of-the-art architectures rely on only nearest-neighbor coupling. Here, we implement a random access superconducting quantum information processor, demonstrating universal operations on a nine-qubit memory, with a Josephson junction transmon circuit serving as the central processor. The quantum memory uses the eigenmodes of a linear array of coupled superconducting resonators. We selectively stimulate vacuum Rabi oscillations between the transmon and individual eigenmodes through parametric flux modulation of the transmon frequency. Utilizing these oscillations, we perform a universal set of quantum gates on 38 arbitrary pairs of modes and prepare multimode entangled states, all using only two control lines. We thus achieve hardware-efficient random access multi-qubit control in an architecture compatible with long-lived microwave cavity-based quantum memories.

8.
Phys Rev Lett ; 119(26): 264801, 2017 Dec 29.
Article in English | MEDLINE | ID: mdl-29328733

ABSTRACT

In niobium superconducting radio frequency (SRF) cavities for particle acceleration, a decrease of the quality factor at lower fields-a so-called low field Q slope or LFQS-has been a long-standing unexplained effect. By extending the high Q measurement techniques to ultralow fields, we discover two previously unknown features of the effect: (i) saturation at rf fields lower than E_{acc}∼0.1 MV/m; (ii) strong degradation enhancement by growing thicker niobium pentoxide. Our findings suggest that the LFQS may be caused by the two level systems in the natural niobium oxide on the inner cavity surface, thereby identifying a new source of residual resistance and providing guidance for potential nonaccelerator low-field applications of SRF cavities.

9.
Laryngorhinootologie ; 95(9): 640-52, 2016 Sep.
Article in German | MEDLINE | ID: mdl-27626817

Subject(s)
Tracheotomy , Humans
10.
Eur J Med Chem ; 124: 49-62, 2016 Nov 29.
Article in English | MEDLINE | ID: mdl-27560282

ABSTRACT

The peroxisome proliferator-activated receptor (PPAR) γ regulates the expression of genes involved in adipogenesis, lipid homeostasis, and glucose metabolism, making it a valuable drug target. However, full activation of the nuclear receptor is associated with unwanted side effects. Research therefore focuses on the discovery of novel partial agonists, which show a distinct protein-ligand interaction pattern compared to full agonists. Within this study, we employed pharmacophore- and shape-based virtual screening and docking independently and in parallel for the identification of novel PPARγ ligands. The ten top-ranked hits retrieved with every method were further investigated with external in silico bioactivity profiling tools. Subsequent biological testing not only confirmed the binding of nine out of the 29 selected test compounds, but enabled the direct comparison of the method performances in a prospective manner. Although all three methods successfully identified novel ligands, they varied in the numbers of active compounds ranked among the top-ten in the virtual hit list. In addition, these compounds were in most cases exclusively predicted as active by the method which initially identified them. This suggests, that the applied programs and methods are highly complementary and cover a distinct chemical space of PPARγ ligands. Further analyses revealed that eight out of the nine active molecules represent novel chemical scaffolds for PPARγ, which can serve as promising starting points for further chemical optimization. In addition, two novel compounds, identified with docking, proved to be partial agonists in the experimental testing.


Subject(s)
Drug Evaluation, Preclinical/methods , Drug Partial Agonism , PPAR gamma/agonists , Animals , COS Cells , Chlorocebus aethiops , Molecular Docking Simulation , PPAR gamma/chemistry , PPAR gamma/metabolism , Protein Conformation , User-Computer Interface
11.
BJR Case Rep ; 1(3): 20150060, 2015.
Article in English | MEDLINE | ID: mdl-30363554

ABSTRACT

Sarcoid-like reaction (SLR) is a cause of non-caseating granulomas in some of the cancer patients with otherwise no signs or symptoms of sarcoidosis. SLR has been described in a variety of solid organ malignancies, including breast and lung cancer. SLR may result in hypermetabolic activity in 18-fludeoxyglucose positron emission tomography (PET)/CT scan, resulting in false positive reporting for malignancy. The purpose of this case series is to expose residents/practising physicians who interpret PET/CT to a series of cases illustrating findings of SLR.

12.
Br J Pharmacol ; 172(2): 388-402, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24641506

ABSTRACT

UNLABELLED: Opioid and α2 -adrenoceptor agonists are potent analgesic drugs and their analgesic effects can synergize when co-administered. These supra-additive interactions are potentially beneficial clinically; by increasing efficacy and/or reducing the total drug required to produce sufficient pain relief, undesired side effects can be minimized. However, combination therapies of opioids and α2 -adrenoceptor agonists remain underutilized clinically, in spite of a large body of preclinical evidence describing their synergistic interaction. One possible obstacle to the translation of preclinical findings to clinical applications is a lack of understanding of the mechanisms underlying the synergistic interactions between these two drug classes. In this review, we provide a detailed overview of the interactions between different opioid and α2 -adrenoceptor agonist combinations in preclinical studies. These studies have identified the spinal cord as an important site of action of synergistic interactions, provided insights into which receptors mediate these interactions and explored downstream signalling events enabling synergy. It is now well documented that the activation of both µ and δ opioid receptors can produce synergy with α2 -adrenoceptor agonists and that α2 -adrenoceptor agonists can mediate synergy through either the α2A or the α2C adrenoceptor subtypes. Current hypotheses surrounding the cellular mechanisms mediating opioid-adrenoceptor synergy, including PKC signalling and receptor oligomerization, and the evidence supporting them are presented. Finally, the implications of these findings for clinical applications and drug discovery are discussed. LINKED ARTICLES: This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.


Subject(s)
Receptors, Adrenergic, alpha-2/metabolism , Receptors, Opioid/metabolism , Adrenergic alpha-Agonists/pharmacokinetics , Adrenergic alpha-Agonists/pharmacology , Analgesia , Analgesics, Opioid/pharmacology , Animals , Drug Synergism , Humans
13.
Z Gerontol Geriatr ; 48(2): 176-83, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25119700

ABSTRACT

BACKGROUND: In all, 39 % of people living in Swiss nursing homes suffer from dementia. Detailed data about type and course of symptoms displayed by these patients in their terminal phase are lacking. METHODS: This descriptive, retrospective study analysed 65 nursing documents from deceased people with dementia in four nursing homes in the canton of Zurich, Switzerland. RESULTS: Difficulties with mobility (81 %), pain (71 %) and sleep disturbance (63 %) were the most frequent of the 10 identified symptoms. Towards the end of life, difficulties with mobility, sleep disturbance, agitation and other neuropsychiatric symptoms, such as episodes of depression, decreased (decrescent pattern), while pain, feeding problems, breathing abnormalities, apathy and anxiety increased (crescent pattern). Courses of pain were documented in 17 % of the nursing records. In addition, 76 % of the residents had been visited on a daily basis by next of kin in their last 7 days, compared with only one third of residents previously. Furthermore, daily communication between healthcare professionals and next of kin tripled during this period. CONCLUSION: The documented prevalence of a high and increasing level of pain towards the end of life, combined with the lack of documented courses of pain, shows potential for improvement in pain relief and pain identification for patients with dementia in their terminal phase. The increasing number of visits by next of kin and the increasingly intensive contact between healthcare professionals and next of kin in the last 7 days are a strong indicator that the end of life can be predicted relatively well by the involved participants and appropriate reactions follow.


Subject(s)
Dementia/diagnosis , Dementia/mortality , Homes for the Aged/statistics & numerical data , Nursing Homes/statistics & numerical data , Palliative Care/statistics & numerical data , Terminal Care/statistics & numerical data , Aged, 80 and over , Anxiety/diagnosis , Anxiety/mortality , Anxiety/psychology , Dementia/psychology , Depression/diagnosis , Depression/mortality , Depression/psychology , Female , Humans , Length of Stay/statistics & numerical data , Male , Pain/diagnosis , Pain/mortality , Pain/psychology , Palliative Care/psychology , Sleep Wake Disorders/diagnosis , Sleep Wake Disorders/mortality , Sleep Wake Disorders/psychology , Survival Rate , Switzerland/epidemiology , Symptom Assessment/statistics & numerical data , Terminal Care/psychology
14.
Br J Pharmacol ; 172(2): 642-53, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24827408

ABSTRACT

BACKGROUND AND PURPOSE: We recently found that PKCε was required for spinal analgesic synergy between two GPCRs, δ opioid receptors and α2 A adrenoceptors, co-located in the same cellular subpopulation. We sought to determine if co-delivery of µ and δ opioid receptor agonists would similarly result in synergy requiring PKCε. EXPERIMENTAL APPROACH: Combinations of µ and δ opioid receptor agonists were co-administered intrathecally by direct lumbar puncture to PKCε-wild-type (PKCε-WT) and -knockout (PKCε-KO) mice. Antinociception was assessed using the hot-water tail-flick assay. Drug interactions were evaluated by isobolographic analysis. KEY RESULTS: All agonists produced comparable antinociception in both PKCε-WT and PKCε-KO mice. Of 19 agonist combinations that produced analgesic synergy, only 3 required PKCε for a synergistic interaction. In these three combinations, one of the agonists was morphine, although not all combinations involving morphine required PKCε. Morphine + deltorphin II and morphine + deltorphin I required PKCε for synergy, whereas a similar combination, morphine + deltorphin, did not. Additionally, morphine + oxymorphindole required PKCε for synergy, whereas a similar combination, morphine + oxycodindole, did not. CONCLUSIONS AND IMPLICATIONS: We discovered biased agonism for a specific signalling pathway at the level of spinally co-delivered opioid agonists. As the bias is only revealed by an appropriate ligand combination and cannot be accounted for by a single drug, it is likely that the receptors these agonists act on are interacting with each other. Our results support the existence of µ and δ opioid receptor heteromers at the spinal level in vivo. LINKED ARTICLES: This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.


Subject(s)
Analgesics, Opioid/pharmacology , Analgesics, Opioid/therapeutic use , Pain/drug therapy , Protein Kinase C-epsilon/metabolism , Receptors, Opioid, delta/metabolism , Receptors, Opioid, mu/metabolism , Animals , Behavior, Animal/drug effects , Drug Therapy, Combination , Female , Hot Temperature , Ligands , Male , Mice, Knockout , Morphine/pharmacology , Morphine/therapeutic use , Morpholines/pharmacology , Morpholines/therapeutic use , Oligopeptides/pharmacology , Oligopeptides/therapeutic use , Pain/metabolism , Protein Multimerization , Receptors, Opioid, delta/agonists , Receptors, Opioid, mu/agonists , Spinal Cord/metabolism
15.
Br J Pharmacol ; 171(9): 2399-412, 2014 May.
Article in English | MEDLINE | ID: mdl-24467325

ABSTRACT

BACKGROUND AND PURPOSE: 1,4-Benzoquinones are well-known inhibitors of 5-lipoxygenase (5-LOX, the key enzyme in leukotriene biosynthesis), but the molecular mechanisms of 5-LOX inhibition are not completely understood. Here we investigated the molecular mode of action and the pharmacological profile of the novel 1,4-benzoquinone derivative 3-((decahydronaphthalen-6-yl)methyl)-2,5-dihydroxycyclohexa-2,5-diene-1,4-dione (RF-Id) in vitro and its effectiveness in vivo. EXPERIMENTAL APPROACH: Mechanistic investigations in cell-free assays using 5-LOX and other enzymes associated with eicosanoid biosynthesis were conducted, along with cell-based studies in human leukocytes and whole blood. Molecular docking of RF-Id into the 5-LOX structure was performed to illustrate molecular interference with 5-LOX. The effectiveness of RF-Id in vivo was also evaluated in two murine models of inflammation. KEY RESULTS: RF-Id consistently suppressed 5-LOX product synthesis in human leukocytes and human whole blood. RF-Id also blocked COX-2 activity but did not significantly inhibit COX-1, microsomal PGE2 synthase-1, cytosolic PLA2 or 12- and 15-LOX. Although RF-Id lacked radical scavenging activity, reducing conditions facilitated its inhibitory effect on 5-LOX whereas cell stress impaired its efficacy. The reduced hydroquinone form of RF-Id (RED-RF-Id) was a more potent inhibitor of 5-LOX as it had more bidirectional hydrogen bonds within the 5-LOX substrate binding site. Finally, RF-Id had marked anti-inflammatory effects in mice in vivo. CONCLUSIONS AND IMPLICATIONS: RF-Id represents a novel anti-inflammatory 1,4-benzoquinone that potently suppresses LT biosynthesis by direct inhibition of 5-LOX with effectiveness in vivo. Mechanistically, RF-Id inhibits 5-LOX in a non-redox manner by forming discrete molecular interactions within the active site of 5-LOX.


Subject(s)
Anti-Inflammatory Agents/chemistry , Benzoquinones/chemistry , Lipoxygenase Inhibitors/chemistry , Molecular Docking Simulation , Animals , Anti-Inflammatory Agents/metabolism , Anti-Inflammatory Agents/therapeutic use , Benzoquinones/metabolism , Benzoquinones/therapeutic use , Edema/drug therapy , Edema/metabolism , Humans , Lipoxygenase Inhibitors/metabolism , Lipoxygenase Inhibitors/therapeutic use , Male , Mice , Molecular Docking Simulation/methods , Protein Structure, Secondary , Sheep , Treatment Outcome
16.
Br J Pharmacol ; 171(7): 1676-86, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24329519

ABSTRACT

BACKGROUND AND PURPOSE: The transcription factor NF-κB orchestrates many pro-inflammatory signals and its inhibition is considered a promising strategy to combat inflammation. Here we report the characterization of the natural product plumericin as a highly potent inhibitor of the NF-κB pathway with a novel chemical scaffold, which was isolated via a bioactivity-guided approach, from extracts of Himatanthus sucuuba, an Amazonian plant traditionally used to treat inflammation-related disorders. EXPERIMENTAL APPROACH: A NF-κB luciferase reporter gene assay was used to identify NF-κB pathway inhibitors from H. sucuuba extracts. Monitoring of TNF-α-induced expression of the adhesion molecules VCAM-1, ICAM-1 and E-selectin by flow cytometry was used to confirm NF-κB inhibition in endothelial cells, and thioglycollate-induced peritonitis in mice to confirm effects in vivo. Western blotting and transfection experiments were used to investigate the mechanism of action of plumericin. KEY RESULTS: Plumericin inhibited NF-κB-mediated transactivation of a luciferase reporter gene (IC50 1 µM), abolished TNF-α-induced expression of the adhesion molecules VCAM-1, ICAM-1 and E-selectin in endothelial cells and suppressed thioglycollate-induced peritonitis in mice. Plumericin exerted its NF-κB pathway inhibitory effect by blocking IκB phosphorylation and degradation. Plumericin also inhibited NF-κB activation induced by transfection with the constitutively active catalytic subunit of the IκB kinase (IKK-ß), suggesting IKK involvement in the inhibitory action of this natural product. CONCLUSION AND IMPLICATIONS: Plumericin is a potent inhibitor of NF-κB pathways with a new chemical scaffold. It could be further explored as a novel anti-inflammatory lead compound.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Indenes/pharmacology , Inflammation Mediators/antagonists & inhibitors , Inflammation/prevention & control , Iridoids/pharmacology , NF-kappa B/antagonists & inhibitors , Plant Extracts/pharmacology , Animals , Apocynaceae , Cell Adhesion Molecules/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , HEK293 Cells , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/immunology , Human Umbilical Vein Endothelial Cells/metabolism , Humans , I-kappa B Kinase/metabolism , I-kappa B Proteins/metabolism , Inflammation/chemically induced , Inflammation/genetics , Inflammation/immunology , Inflammation/metabolism , Inflammation Mediators/metabolism , Male , Mice , Mice, Inbred C57BL , NF-kappa B/genetics , NF-kappa B/metabolism , Phosphorylation , Signal Transduction/drug effects , Thioglycolates , Transfection
17.
Rev Sci Instrum ; 84(2): 025116, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23464260

ABSTRACT

We discuss the design and implementation of thin film superconducting coplanar waveguide micro-resonators for pulsed electron spin resonance experiments. The performance of the resonators with P doped Si epilayer samples is compared to waveguide resonators under equivalent conditions. The high achievable filling factor even for small sized samples and the relatively high Q-factor result in a sensitivity of 4.5 × 10(8) spins per shot, which is superior to that of conventional waveguide resonators, in particular to spins close to the sample surface. The peak microwave power is on the order of a few milliwatts, which is compatible with measurements at ultra-low temperatures. We also discuss the effect of the nonuniform microwave magnetic field on the Hahn echo power dependence.

18.
J Psychiatr Ment Health Nurs ; 20(7): 613-22, 2013 Sep.
Article in English | MEDLINE | ID: mdl-22762380

ABSTRACT

In the 20th century, houseparent families represented a significant resource in the long-term care of people with mental illnesses and physical disabilities in diaconical care settings in Germany. In theory, such families could therefore be understood as a type of institutional family: groups which occasionally use familial patterns of reciprocity but are not themselves families. As little empirical material on life in institutional families existed, a qualitative study was undertaken to explore the experiences of contemporary witnesses, particularly those who had experienced the duties and responsibilities of housemothers in the second half of the 20th century. This paper has combined the experiences of residents (n= 8) and biological children of houseparents (n= 5) from a qualitative study (n= 42). The qualitative study took a grounded theory approach, with the phenomena of power and domination forming the central category. The findings show that life in houseparent families of the time was shaped by rules which the family members had to obey. This study explores a highly controversial area which is of great relevance for current mental health nursing practice: the power relations in diaconal families. This demonstrates the importance of integrating autonomy and empowerment into everyday communal life and contributes to professional nursing practice.


Subject(s)
Mental Disorders/nursing , Nursing Homes/history , Psychiatric Nursing/history , Family Relations , History, 20th Century , Humans , Nursing Homes/organization & administration , Power, Psychological , Psychiatric Nursing/organization & administration , Qualitative Research
19.
Neurogastroenterol Motil ; 25(2): e89-100, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23252426

ABSTRACT

BACKGROUND: Primary afferent neurons whose cell bodies reside in thoracolumbar and lumbosacral dorsal root ganglia (DRG) innervate colon and transmit sensory signals from colon to spinal cord under normal conditions and conditions of visceral hypersensitivity. Histologically, these extrinsic afferents cannot be differentiated from intrinsic fibers of enteric neurons because all known markers label neurons of both populations. Adeno-associated virus (AAV) vectors are capable of transducing DRG neurons after intrathecal administration. We hypothesized that AAV-driven overexpression of green fluorescent protein (GFP) in DRG would enable visualization of extrinsic spinal afferents in colon separately from enteric neurons. METHODS: Recombinant AAV serotype 8 (rAAV8) vector carrying the GFP gene was delivered via direct lumbar puncture. Green fluorescent protein labeling in DRG and colon was examined using immunohistochemistry. KEY RESULTS: Analysis of colon from rAAV8-GFP-treated mice demonstrated GFP-immunoreactivity (GFP-ir) within mesenteric nerves, smooth muscle layers, myenteric plexus, submucosa, and mucosa, but not in cell bodies of enteric neurons. Notably, GFP-ir colocalized with CGRP and TRPV1 in mucosa, myenteric plexus, and globular-like clusters surrounding nuclei within myenteric ganglia. In addition, GFP-positive fibers were observed in close association with blood vessels of mucosa and submucosa. Analysis of GFP-ir in thoracolumbar and lumbosacral DRG revealed that levels of expression in colon and L6 DRG appeared to be related. CONCLUSIONS & INFERENCES: These results demonstrate the feasibility of gene transfer to mouse colonic spinal sensory neurons using intrathecal delivery of AAV vectors and the utility of this approach for histological analysis of spinal afferent nerve fibers within colon.


Subject(s)
Colon/innervation , Gene Transfer Techniques , Green Fluorescent Proteins , Neurons, Afferent/cytology , Animals , Dependovirus/genetics , Ganglia, Spinal , Genetic Vectors , Immunohistochemistry , Mice , Myenteric Plexus , Transduction, Genetic/methods
20.
Acta Biomater ; 9(3): 5689-97, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23168223

ABSTRACT

The work presented here shows for the first time that it is possible to silicify S-layer coated liposomes and to obtain stable functionalized hollow nano-containers. For this purpose, the S-layer protein of Geobacillus stearothermophilus PV72/p2 was recombinantly expressed and used for coating positively charged liposomes composed of dipalmitoylphosphatidylcholine, cholesterol and hexadecylamine in a molar ratio of 10:5:4. Subsequently, plain (uncoated) liposomes and S-layer coated liposomes were silicified. Determination of the charge of the constructs during silicification allowed the deposition process to be followed. After the particles had been silicified, lipids were dissolved by treatment with Triton X-100 with the release of previously entrapped fluorescent dyes being determined by fluorimetry. Both, ζ-potential and release experiments showed differences between silicified plain liposomes and silicified S-layer coated liposomes. The results of the individual preparation steps were examined by embedding the respective assemblies in resin, ultrathin sectioning and inspection by bright-field transmission electron microscopy (TEM). Energy filtered TEM confirmed the successful construction of S-layer based silica cages. It is anticipated that this approach will provide a key to enabling technology for the fabrication of nanoporous protein cages for applications ranging from nano medicine to materials science.


Subject(s)
Liposomes/chemical synthesis , Membrane Glycoproteins/chemical synthesis , Silicon Dioxide/chemistry , Crystallization , Fluoresceins/metabolism , Geobacillus stearothermophilus/chemistry , Isoelectric Point , Liposomes/ultrastructure , Membrane Glycoproteins/ultrastructure , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Reproducibility of Results , Time Factors
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