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1.
BMC Genomics ; 17: 701, 2016 09 02.
Article in English | MEDLINE | ID: mdl-27590662

ABSTRACT

BACKGROUND: The common carp (Cyprinus carpio) is the oldest, most domesticated and one of the most cultured fish species for food consumption. Besides its economic importance, the common carp is also highly suitable for comparative physiological and disease studies in combination with the animal model zebrafish (Danio rerio). They are genetically closely related but offer complementary benefits for fundamental research, with the large body mass of common carp presenting possibilities for obtaining sufficient cell material for advanced transcriptome and proteome studies. RESULTS: Here we have used 19 different tissues from an F1 hybrid strain of the common carp to perform transcriptome analyses using RNA-Seq. For a subset of the tissues we also have performed deep proteomic studies. As a reference, we updated the European common carp genome assembly using low coverage Pacific Biosciences sequencing to permit high-quality gene annotation. These annotated gene lists were linked to zebrafish homologs, enabling direct comparisons with published datasets. Using clustering, we have identified sets of genes that are potential selective markers for various types of tissues. In addition, we provide a script for a schematic anatomical viewer for visualizing organ-specific expression data. CONCLUSIONS: The identified transcriptome and proteome data for carp tissues represent a useful resource for further translational studies of tissue-specific markers for this economically important fish species that can lead to new markers for organ development. The similarity to zebrafish expression patterns confirms the value of common carp as a resource for studying tissue-specific expression in cyprinid fish. The availability of the annotated gene set of common carp will enable further research with both applied and fundamental purposes.


Subject(s)
Carps/genetics , Carps/metabolism , Proteome , Transcriptome , Animals , Computational Biology/methods , Europe , Gene Expression Profiling , Genome , Genomics/methods , High-Throughput Nucleotide Sequencing , Molecular Sequence Annotation , Organ Specificity , Proteomics
2.
Phys Rev Lett ; 117(10): 100402, 2016 Sep 02.
Article in English | MEDLINE | ID: mdl-27636458

ABSTRACT

Recent progress in manipulating atomic and condensed matter systems has instigated a surge of interest in nonequilibrium physics, including many-body dynamics of trapped ultracold atoms and ions, near-field radiative heat transfer, and quantum friction. Under most circumstances the complexity of such nonequilibrium systems requires a number of approximations to make theoretical descriptions tractable. In particular, it is often assumed that spatially separated components of a system thermalize with their immediate surroundings, although the global state of the system is out of equilibrium. This powerful assumption reduces the complexity of nonequilibrium systems to the local application of well-founded equilibrium concepts. While this technique appears to be consistent for the description of some phenomena, we show that it fails for quantum friction by underestimating by approximately 80% the magnitude of the drag force. Our results show that the correlations among the components of driven, but steady-state, quantum systems invalidate the assumption of local thermal equilibrium, calling for a critical reexamination of this approach for describing the physics of nonequilibrium systems.

3.
Phys Rev Lett ; 111(23): 231101, 2013 Dec 06.
Article in English | MEDLINE | ID: mdl-24476248

ABSTRACT

A limit on a possible cosmological variation of the proton-to-electron mass ratio µ is derived from methanol (CH3OH) absorption lines in the benchmark PKS1830-211 lensing galaxy at redshift z=0.89 observed with the Effelsberg 100-m radio telescope, the Institute de Radio Astronomie Millimétrique 30-m telescope, and the Atacama Large Millimeter/submillimeter Array. Ten different absorption lines of CH3OH covering a wide range of sensitivity coefficients K(µ) are used to derive a purely statistical 1σ constraint of Δµ/µ=(1.5±1.5)×10(-7) for a lookback time of 7.5 billion years. Systematic effects of chemical segregation, excitation temperature, frequency dependence, and time variability of the background source are quantified. A multidimensional linear regression analysis leads to a robust constraint of Δµ/µ=(-1.0±0.8(stat)±1.0(sys))×10(-7).

4.
Emerg Microbes Infect ; 12(1): 2164216, 2023 12.
Article in English | MEDLINE | ID: mdl-36580440

ABSTRACT

Ebolaviruses cause outbreaks of haemorrhagic fever in Central and West Africa. Some members of this genus such as Ebola virus (EBOV) are highly pathogenic, with case fatality rates of up to 90%, whereas others such as Reston virus (RESTV) are apathogenic for humans. Bombali virus (BOMV) is a novel ebolavirus for which complete genome sequences were recently found in free-tailed bats, although no infectious virus could be isolated. Its pathogenic potential for humans is unknown. To address this question, we first determined whether proteins encoded by the available BOMV sequence found in Chaerephon pumilus were functional in in vitro assays. The correction of an apparent sequencing error in the glycoprotein based on these data then allowed us to generate infectious BOMV using reverse genetics and characterize its infection of human cells. Furthermore, we used HLA-A2-transgenic, NOD-scid-IL-2γ receptor-knockout (NSG-A2) mice reconstituted with human haematopoiesis as a model to evaluate the pathogenicity of BOMV in vivo in a human-like immune environment. These data demonstrate that not only does BOMV show a slower growth rate than EBOV in vitro, but it also shows low pathogenicity in humanized mice, comparable to previous studies using RESTV. Taken together, these findings suggest a low pathogenic potential of BOMV for humans.


Subject(s)
Ebolavirus , Hemorrhagic Fever, Ebola , Humans , Animals , Mice , Ebolavirus/genetics , Mice, Inbred NOD , Animals, Genetically Modified , Africa, Western
5.
Proc Math Phys Eng Sci ; 478(2264): 20220132, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35937429

ABSTRACT

The wetting of soft polymer substrates brings in multiple complexities when compared with the wetting on rigid substrates. The contact angle of the liquid is no longer governed by Young's Law, but is affected by the substrate's bulk and surface deformations. On top of that, elastic interfaces exhibit a surface energy that depends on how much they are stretched-a feature known as the Shuttleworth effect (or as surface-elasticity). Here, we present two models through which we explore the wetting of drops in the presence of a strong Shuttleworth effect. The first model is macroscopic in character and consistently accounts for large deformations via a neo-Hookean elasticity. The second model is based on a mesoscopic description of wetting, using a reduced description of the substrate's elasticity. While the second model is more empirical in terms of the elasticity, it enables a gradient dynamics formulation for soft wetting dynamics. We provide a detailed comparison between the equilibrium states predicted by the two models, from which we deduce robust features of soft wetting in the presence of a strong Shuttleworth effect. Specifically, we show that the (a)symmetry of the Shuttleworth effect between the 'dry' and 'wet' states governs horizontal deformations in the substrate. Our results are discussed in the light of recent experiments on the wettability of stretched substrates.

6.
Nanotechnology ; 22(3): 035201, 2011 Jan 21.
Article in English | MEDLINE | ID: mdl-21149968

ABSTRACT

In this work, we demonstrate an approach to tune the electrical behavior of our Ω-gated germanium-nanowire (Ge-NW) MOSFETs by focused ion beam (FIB) implantation. For the MOSFETs, 35 nm thick Ge-NWs are covered by atomic layer deposition (ALD) of a high-κ gate dielectric. With the Ω-shaped metal gate acting as implantation mask, highly doped source/drain (S/D) contacts are formed in a self-aligned process by FIB implantation. Notably, without any dopant activation by annealing, the devices exhibit more than three orders of magnitude higher I(ON) currents, an improved I(ON)/I(OFF) ratio, a higher mobility and a reduced subthreshold slope of 140 mV/decade compared to identical Ge-NW MOSFETs without FIB implantation.

7.
Microelectron Eng ; 88(3): 262-267, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21461054

ABSTRACT

Schottky barrier SOI-MOSFETs incorporating a La(2)O(3)/ZrO(2) high-k dielectric stack deposited by atomic layer deposition are investigated. As the La precursor tris(N,N'-diisopropylformamidinato) lanthanum is used. As a mid-gap metal gate electrode TiN capped with W is applied. Processing parameters are optimized to issue a minimal overall thermal budget and an improved device performance. As a result, the overall thermal load was kept as low as 350, 400 or 500 °C. Excellent drive current properties, low interface trap densities of 1.9 × 10(11) eV(-1) cm(-2), a low subthreshold slope of 70-80 mV/decade, and an I(ON)/I(OFF) current ratio greater than 2 × 10(6) are obtained.

8.
BMC Res Notes ; 14(1): 42, 2021 Feb 02.
Article in English | MEDLINE | ID: mdl-33531031

ABSTRACT

OBJECTIVE: Currently the majority of non-culturable microbes in sea water are yet to be discovered, Nanopore offers a solution to overcome the challenging tasks to identify the genomes and complex composition of oceanic microbiomes. In this study we evaluate the utility of Oxford Nanopore Technologies (ONT) sequencing to characterize microbial diversity in seawater from multiple locations. We compared the microbial species diversity of retrieved environmental samples from two different locations and time points. RESULTS: With only three ONT flow cells we were able to identify thousands of organisms, including bacteriophages, from which a large part at species level. It was possible to assemble genomes from environmental samples with Flye. In several cases this resulted in > 1 Mbp contigs and in the particular case of a Thioglobus singularis species it even produced a near complete genome. k-mer analysis reveals that a large part of the data represents species of which close relatives have not yet been deposited to the database. These results show that our approach is suitable for scalable genomic investigations such as monitoring oceanic biodiversity and provides a new platform for education in biodiversity.


Subject(s)
High-Throughput Nucleotide Sequencing , Nanopores , Pilot Projects , Seawater , Sequence Analysis, DNA
9.
Nano Lett ; 9(5): 1830-4, 2009 May.
Article in English | MEDLINE | ID: mdl-19323479

ABSTRACT

In this letter, we demonstrate the simultaneous vertical integration of self-contacting and highly oriented nanowires (NWs) into airbridge structures, which have been developed into surround gated metal oxide semiconductor field effect transistors (MOSFETs). With the use of conventional photolithography, reactive ion etching (RIE), and low pressure chemical vapor deposition, a suspended vertical NW architecture is formed on a silicon on insulator (SOI) substrate where the nanodevice will later be fabricated on. The vapor-liquid-solid (VLS) grown Si-NWs are contacted to prepatterned airbridges by a self-aligned process, and there is no need for postgrowth NW assembly or alignment. Such vertical NW architecture can be easily integrated into existing ICs processes opening the path to a new generation of nonconventional nano devices. To demonstrate the potential of this method, surround gated vertical MOSFETs have been fabricated with a highly simplified integration scheme combining top-down and bottom-up approaches, but in the same way, one can think about the realization of integrated nano sensors on the industrial scale.

10.
Pathologe ; 31 Suppl 2: 234-8, 2010 Oct.
Article in German | MEDLINE | ID: mdl-20665023

ABSTRACT

Results of molecular pathology have supported changes in the 2004 WHO classification of urothelial cancer. Since then new molecular data such as the distribution pattern of the fibroblast growth factor receptor 3 (FGFR3) has further supported the principle of low and high grade entities of urothelial carcinoma. Animal experiments with knockout mice and conditional knockout systems reveal important parallels to humans and results emphasize the cellular context as a trigger for malignancy. One special feature of the urothelium is its high protection of the urothelial cells by members of the retinoblastoma gene family, efficiently inhibiting invasion even in the presence of p53 mutations. In search of the tumor stem cell phenotype the basal cell phenotype is the focus of attention providing a high clonogenic potential. At the same time detailed analysis of the distribution of mutations in the mitochondrial genome within the urothelium will help to gain insight into the spreading of normal cell or tumor cell clones. The overall data in urological oncology provide evidence that diagnostic and prognostic tools for urothelial cancer can only be reached with multiparametric approaches.


Subject(s)
Carcinoma, Transitional Cell/genetics , Carcinoma, Transitional Cell/pathology , Receptor, Fibroblast Growth Factor, Type 3/genetics , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/pathology , Animals , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/pathology , Chromosomes, Human, Pair 19/genetics , Cyclin-Dependent Kinase Inhibitor p16 , DNA Mutational Analysis , Genes, Retinoblastoma/genetics , Humans , Mice , Mice, Knockout , Neoplasm Invasiveness/genetics , Neoplasm Invasiveness/pathology , Neoplasm Proteins/genetics , Neoplasm Staging , Neoplastic Stem Cells/pathology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Tumor Suppressor Protein p53/genetics , Urothelium/pathology
11.
Neuroscience ; 154(1): 346-54, 2008 Jun 12.
Article in English | MEDLINE | ID: mdl-18372115

ABSTRACT

Axonal projections from the dorsal nucleus of the lateral lemniscus (DNLL) distribute contralaterally in a pattern of banded layers in the central nucleus of the inferior colliculus (IC). The banded pattern of DNLL projections is already in the IC by onset of hearing in postnatal rat pups. Previously, it was shown that unilateral cochlear ablation in neonatal rat pups disrupted the banded pattern in IC for the projections of the DNLL contralateral to the ablation but not those of the DNLL ipsilateral to the ablation. In the present study, bilateral cochlear ablation or sham surgery was performed at postnatal day 9 (P9) after which rat pups were killed at P12 and the brains removed to study axonal projections of the DNLL. A lipophilic carbocyanine dye, 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI), was placed in the dorsal tegmental commissure of Probst to label decussating DNLL axons that end in the central nucleus of the contralateral IC. The distribution of labeled fibers across the central nucleus of the IC was analyzed in digital images by comparing the pattern of labeling with a sine model of periodic distribution of banded layers. In the control group, labeled axons formed a regular pattern of dense banded layers in IC. In the bilateral cochlear ablation group, labeled axons in the IC were distributed diffusely and there was little or no regular pattern of dense bands of axonal labeling. The influence of the cochlea on developing auditory circuits possibly mediated by activity-dependent mechanisms is discussed.


Subject(s)
Cochlea/injuries , Cochlea/physiopathology , Functional Laterality/physiology , Inferior Colliculi/pathology , Inferior Colliculi/physiopathology , Neurons/pathology , Amino Acids , Animals , Animals, Newborn , Auditory Pathways/physiopathology , Models, Neurological , Multivariate Analysis , Rats , Time Factors
12.
Neuroscience ; 146(1): 225-35, 2007 Apr 25.
Article in English | MEDLINE | ID: mdl-17324524

ABSTRACT

Axonal projections from the lateral superior olivary nuclei (LSO), as well as from the dorsal cochlear nucleus (DCN) and dorsal nucleus of the lateral lemniscus (DNLL), converge in frequency-ordered layers in the central nucleus of the inferior colliculus (IC) where they distribute among different synaptic compartments. A carbocyanine dye, 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI), was used as a tracer to study the postnatal development of axonal projections in the ferret IC. The results indicated that projections from all three nuclei are present at birth, but are not segregated into bands. During the postnatal week between approximately postnatal days 4 and 12 (P4-P12), axons from LSO proliferate in IC, become more branched, and segregate into a series of bands composed of densely packed fibers and endings. LSO projections in these afferent bands course parallel to IC layers and are separated by intervening regions with few endings. A modest fit of a sine curve (R2>0.15) to the pattern of spacing of LSO projections in IC indicated that regularly spaced bands are forming by P7. Similarly, banded patterns of DCN and DNLL projections to IC have developed by the end of the first postnatal week. Thus, well before hearing onset in ferret (P28-30), three different afferent projections have segregated into banded compartments along layers in the central nucleus of the ferret IC. Possible mechanisms in circuit development are discussed.


Subject(s)
Auditory Pathways/growth & development , Critical Period, Psychological , Hearing/physiology , Inferior Colliculi/growth & development , Age Factors , Animals , Animals, Newborn , Auditory Pathways/metabolism , Carbocyanines/metabolism , Ferrets , Functional Laterality , Inferior Colliculi/metabolism
13.
Neuroscience ; 148(4): 1033-47, 2007 Sep 21.
Article in English | MEDLINE | ID: mdl-17764853

ABSTRACT

Afferent activity modulates synaptic plasticity as well as the levels of activity-dependent molecules such as growth factors. Disruption of this activity due to deafferentation has been shown to result in an altered trophic support and consequently in changes in neuronal excitability and synaptic transmission. In the present study, to test whether lack of cochlear integrity results in changes in insulin-growth factor-1 (IGF-1) and synaptophysin immunostaining in the cochlear nucleus, the first relay structure in the auditory pathway, unilateral cochlear ablations were performed in adult ferrets. Changes in IGF-1 and synaptophysin immunostaining were assessed in the anteroventral (AVCN), posteroventral (PVCN) and dorsal cochlear nucleus (DCN) at 1, 20 and 90 days after deafferentation. An increase in IGF-1 immunostaining within AVCN, PVCN and DCN was observed ipsilaterally at all survival times after cochlear ablation when compared with the contralateral side and unoperated animals. This increase was accompanied by a significant ipsilateral increase in the mean gray level of synaptophysin immunostaining as well as a decrease in the area of synaptophysin immunostaining at 1 and 20 days after the ablation in AVCN, PVCN and DCN compared with the contralateral side and control animals. These changes in synaptophysin immunostaining were no longer present 90 days after cochlear ablation. The present results provide evidence of a persistent upregulation in IGF-1 and a transitory upregulation in synaptophysin levels in the cochlear nucleus that may reflect neuroprotective mechanisms following the loss of trophic support from spiral ganglion neurons.


Subject(s)
Cochlea/surgery , Cochlear Nucleus/metabolism , Gene Expression Regulation/physiology , Insulin-Like Growth Factor I/metabolism , Synaptophysin/metabolism , Animals , Cochlea/innervation , Cochlea/physiology , Ferrets , Functional Laterality , Time Factors
14.
Int J Oncol ; 30(4): 985-92, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17332939

ABSTRACT

Matrix metalloproteinases (MMPs), in particular MMP-2 and MMP-9, are involved in colon cancer progression and metastasis due to their ability to degrade extracellular matrix (ECM) components. In previous studies we described the MMP-9 hemopexin like domain (MMP-9-PEX) as an MMP-9 antagonist. In the present study it was examined whether recombinant MMP-9-PEX has an inhibitory effect on migration and adhesion of colorectal carcinoma cells. Furthermore, we searched for MMP-9 substrate binding sites within the MMP-9-PEX by surface plasmon resonance. Migration of SW620 and LS174 cells was investigated in a modified Boyden chamber assay. In the presence of 0.2 microg/ml MMP-9-PEX migration of SW620 was decreased by 34%, while addition of 0.4 microg/ml diminished migration by 56%. Migration of LS174 cells was not affected by MMP-9-PEX. Adhesion studies were performed on 96-well plates coated with gelatin, collagen type I, and laminin, respectively. In the presence of MMP-9-PEX, adhesion of SW620 cells to these coating substrates was significantly inhibited. Surface plasmon resonance studies revealed binding of collagen type I and IV, elastin, and fibrinogen to proMMP-9 as well as to MMP-9-PEX. However, equilibrium constants (Kd) indicated a higher affinity of proMMP-9 to the matrix proteins. This could indicate that there is more than one binding site for matrix components within the entire proMMP-9 molecule. Since migration and adhesion of metastatic colorectal carcinoma cells were reduced by MMP-9-PEX, this recombinant MMP-9 antagonist might be of therapeutical interest.


Subject(s)
Antineoplastic Agents/pharmacology , Cell Adhesion/drug effects , Cell Movement/drug effects , Colorectal Neoplasms/pathology , Hemopexin/pharmacology , Matrix Metalloproteinase 9/metabolism , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/metabolism , Cell Line, Tumor , Collagen Type I/metabolism , Collagen Type IV/metabolism , Colorectal Neoplasms/enzymology , Elastin/metabolism , Fibrinogen/metabolism , Gelatin/metabolism , Hemopexin/genetics , Hemopexin/isolation & purification , Hemopexin/metabolism , Humans , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/isolation & purification , Matrix Metalloproteinase 9/pharmacology , Protein Structure, Tertiary/genetics , Recombinant Fusion Proteins , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Recombinant Proteins/pharmacology , Surface Plasmon Resonance
15.
Neuroscience ; 143(1): 105-15, 2006 Nov 17.
Article in English | MEDLINE | ID: mdl-16971048

ABSTRACT

During postnatal development, ascending and descending auditory inputs converge to form fibrodendritic layers within the central nucleus of the inferior colliculus (IC). Before the onset of hearing, specific combinations of inputs segregate into bands separated by interband spaces. These bands may define functional zones within the IC. Previous studies in our laboratory have shown that unilateral or bilateral cochlear ablation at postnatal day 2 (P2) disrupts the development of afferent bands from the dorsal nucleus of the lateral lemniscus (DNLL) to the IC. These results suggest that spontaneous activity propagated from the cochlea is required for the segregation of afferent bands within the developing IC. To test if spontaneous activity from the cochlea also may be required to maintain segregated bands of DNLL input, we performed cochlear ablations in rat pups at P9, after DNLL bands already are established. All animals were killed at P12 and glass pins coated with carbocyanine dye, DiI (1,1'-dioctodecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate), subsequently were placed in the commissure of Probst to label the crossed projections from both DNLLs. When compared with surgical controls, experimental results showed a similar pattern of DNLL bands in the IC contralateral to the ablated cochlea, but a disruption of DNLL bands in the IC ipsilateral to the cochlear ablation. The present results suggest that cochlear ablation after DNLL bands have formed may affect the maintenance of banded DNLL projections within the central nucleus of the IC.


Subject(s)
Auditory Pathways/cytology , Cochlea/physiology , Inferior Colliculi/cytology , Inferior Colliculi/growth & development , Neurons, Afferent/cytology , Amino Acids/metabolism , Analysis of Variance , Animals , Animals, Newborn , Auditory Pathways/physiology , Cochlea/surgery , Diagnostic Imaging/methods , Functional Laterality , Rats
16.
Neuroscience ; 136(3): 945-55, 2005.
Article in English | MEDLINE | ID: mdl-16344162

ABSTRACT

The central nucleus of the inferior colliculus (CNIC) is comprised of an orderly series of fibrodendritic layers. These layers include integrative circuitry for as many as 13 different ascending auditory pathways, each tonotopically ordered. Calcium-binding proteins, such as calbindin-D28k (CB), may be useful neurochemical markers for specific subsets of afferent input in these layers and their spatial organization that are developmentally regulated. In this study, CB-immunohistochemistry was used to examine 1-42 postnatal-day-old kitten and adult cat CNIC and anterograde tracers were used to label afferent projections from the lateral superior olivary nucleus (LSO) to the CNIC at similar ages. A distinct axonal plexus that is CB-immunopositive is described. This CB-afferent compartment is present at birth and persists throughout the ages examined. Already at birth, the CB-immunostained plexus in kitten CNIC is organized into discrete bands that are approximately 75 microm thick and 500 microm long. In adult CNIC, the periodic banded pattern of CB-immunostained fibers is similar to that in kittens albeit bands are thicker (145 microm) and longer (700 microm). Growth in band thickness in adult cat appears proportional to growth of the IC, whereas length of the dense CB-immunostained bands is somewhat more focused in the central region of fibrodendritic layers. The banded pattern of the CB-immunostained plexus is well correlated with the location and dimension of afferent projections from the LSO in newborn kitten labeled with carbocyanine dye, 1,1'-dioctodecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate and in adult cat labeled with wheat germ agglutinin conjugated with horseradish peroxidase. The results reveal a neurochemical marker for one type of synaptic compartment in CNIC layers, banding, that is organized before hearing onset in kittens, but that may undergo some postnatal pruning.


Subject(s)
Afferent Pathways/growth & development , Gene Expression Regulation, Developmental/physiology , Inferior Colliculi , S100 Calcium Binding Protein G/metabolism , Afferent Pathways/anatomy & histology , Age Factors , Animals , Animals, Newborn , Calbindins , Carbocyanines/metabolism , Cats , Immunohistochemistry/methods , Inferior Colliculi/cytology , Inferior Colliculi/growth & development , Inferior Colliculi/metabolism , Signal Processing, Computer-Assisted , Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate/metabolism
17.
Neuroscience ; 136(3): 957-69, 2005.
Article in English | MEDLINE | ID: mdl-16344163

ABSTRACT

In the present study, unilateral cochlear ablations were performed in adult ferrets in order to determine whether an upregulation of the calretinin immunostained plexus in the central nucleus of the inferior colliculus occurs and if so, what the time course of this upregulation is. Accordingly, the mean gray level and the calretinin-immunostained area of the axonal plexus in the central nucleus of the inferior colliculus were evaluated at 1, 20 and 90 days after cochlear ablation. In unoperated animals, the calretinin-immunostained plexus was bilaterally symmetric. In ablated animals, both the mean gray level and the immunostained area of the plexus increased in the central nucleus of the inferior colliculus contralateral to the lesion compared with both the ipsilateral side and unoperated animals. This upregulation was present 24 h after the ablation and did not change at the two subsequent time points. In a previous study in young ferrets, the immunostained area of the plexus in the central nucleus of the inferior colliculus contralateral to the lesion increased 200% compared with control ferrets [J Comp Neurol 460 (2003) 585], whereas it increased only 33% in adult ferrets. These findings suggest that 1) calretinin upregulation in the contralateral central nucleus of the inferior colliculus following cochlear ablation occurs by 24 h after cochlear ablation and 2) there is an age-related decline in the magnitude of this upregulation after cochlear ablation.


Subject(s)
Cochlea/surgery , Functional Laterality/physiology , Inferior Colliculi/metabolism , S100 Calcium Binding Protein G/metabolism , Animals , Auditory Pathways/physiology , Calbindin 2 , Cell Count , Cochlea/innervation , Cochlea/physiology , Diagnostic Imaging/methods , Ferrets , Immunohistochemistry/methods , Time Factors , Up-Regulation/physiology
18.
Braz J Med Biol Res ; 48(6): 537-44, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25831200

ABSTRACT

Amfepramone (diethylpropion) is an appetite-suppressant drug used for the treatment of overweight and obesity. It has been suggested that the systemic and central activity of amfepramone produces cardiovascular effects such as transient ischemic attacks and primary pulmonary hypertension. However, it is not known whether amfepramone produces immediate vascular effects when applied in vitro to rat aortic rings and, if so, what mechanisms may be involved. We analyzed the effect of amfepramone on phenylephrine-precontracted rat aortic rings with or without endothelium and the influence of inhibitors or blockers on this effect. Amfepramone produced a concentration-dependent vasorelaxation in phenylephrine-precontracted rat aortic rings that was not affected by the vehicle, atropine, 4-AP, glibenclamide, indomethacin, clotrimazole, or cycloheximide. The vasorelaxant effect of amfepramone was significantly attenuated by NG-nitro-L-arginine methyl ester (L-NAME) and tetraethylammonium (TEA), and was blocked by removal of the vascular endothelium. These results suggest that amfepramone had a direct vasorelaxant effect on phenylephrine-precontracted rat aortic rings, and that inhibition of endothelial nitric oxide synthase and the opening of Ca2+-activated K+ channels were involved in this effect.


Subject(s)
Acetylcholine/pharmacology , Aorta, Thoracic/drug effects , Appetite Depressants/pharmacology , Diethylpropion/pharmacology , Vasodilator Agents/pharmacology , Animals , Aorta, Thoracic/metabolism , Calcium Channels/drug effects , Calcium Channels/metabolism , Endothelium, Vascular/drug effects , Male , NG-Nitroarginine Methyl Ester/metabolism , Nitric Oxide Synthase Type III/drug effects , Phenylephrine/pharmacology , Potassium Channels/drug effects , Potassium Channels/metabolism , Rats, Wistar , Tetraethylammonium/metabolism , Vasoconstrictor Agents/pharmacology , Vasodilation/drug effects
19.
Hypertension ; 30(3 Pt 2): 596-602, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9322988

ABSTRACT

Increased relaxant response to acetylcholine during pregnancy is proposed to be due to an estrogen-mediated increase in nitric oxide release. We studied acetylcholine-induced pathways of relaxation in the thoracic and abdominal aortic rings from pregnant and nonpregnant Wistar-Kyoto rats and measured basal and stimulated release of nitrites in these vessels. Endothelium-dependent relaxation was significantly greater in pregnant than in nonpregnant rats. Acetylcholine provoked a concentration-dependent relaxation on thoracic and abdominal aortic rings from nonpregnant and pregnant rats. After N118-nitro-L-arginine methyl ester pretreatment, the relaxation was significantly inhibited in the two preparations of nonpregnant and pregnant rodents. The relaxation was not inhibited by indomethacin in any of the aortic segments from pregnant and nonpregnant rats. After cytochrome P450 arachidonic acid metabolism inhibitor clotrimazole, a nonsignificant decrease in the Emax to acetylcholine-induced relaxation was observed in the thoracic segments of pregnant and nonpregnant rats. On the other hand, in abdominal aorta, clotrimazole decreased maximal relaxation in rings from pregnant rats (P<.05) but did not change the acetylcholine-induced relaxation from nonpregnant rats. Our results show an increase in the acetylcholine-stimulated release of nitrites in thoracic aortic rings from pregnant rats compared with rings from nonpregnant rats, which cannot be evidenced in abdominal aortic rings. These results suggest that acetylcholine-induced vasodilation in the abdominal segment from pregnant rats is mediated only in part by nitric oxide, the remainder apparently due to an endothelium-derived vasodilator, cytochrome P450-dependent, which may be endothelium-derived hyperpolarizing factor/epoxyeicosatrienoic acid.


Subject(s)
Aorta, Abdominal/physiology , Biological Factors/physiology , Pregnancy, Animal/physiology , Vasodilation/drug effects , Acetylcholine/pharmacology , Animals , Epoprostenol/physiology , Female , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide/physiology , Pregnancy , Rats , Rats, Inbred WKY
20.
J Comp Neurol ; 380(1): 136-44, 1997 Mar 31.
Article in English | MEDLINE | ID: mdl-9073088

ABSTRACT

The distribution and morphology of axons projecting from the medial superior olivary nucleus to the dorsal nucleus of the lateral lemniscus were studied in the adult cat. Injections of Phaseolus vulgaris-leucoagglutinin, biocytin, or dextran-rhodamine in the medial superior olivary nucleus labeled axons that ascended in the lateral lemniscus. Before entering the inferior colliculus, collateral branches of these labeled axons ended in the dorsal nucleus of the lateral lemniscus in thin, horizontal bands forming laminae that extended throughout the rostral-caudal length of the dorsal nucleus of the lateral lemniscus. A dorsal-ventral topography was apparent in the position of the lamina with respect to the injection site, but no relation between the rostral-caudal location of labeled endings and the injection site was observed. There was a divergent pattern of connections within the horizontal laminae rather than a point-to-point organization. The terminal branches of the collateral axons exhibited round or oval boutons en passant and terminaux. Individual arbors reconstructed from serial sections distributed varicosities in circumscribed domains that were only a subcomponent of the area of the afferent laminae in which they were distributed. The spatial relationships of axonal domains of several axons labeled from a single injection in the medial superior olivary nucleus suggest a mosaic pattern in the laminar connections with the dorsal nucleus of the lateral lemniscus.


Subject(s)
Auditory Pathways/physiology , Axons/physiology , Brain Mapping , Cats/physiology , Inferior Colliculi/physiology , Olivary Nucleus/physiology , Afferent Pathways/physiology , Animals , Axons/ultrastructure , Dendrites/physiology , Inferior Colliculi/ultrastructure , Nerve Fibers/physiology , Nerve Fibers/ultrastructure
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