| 1. |
- Ackermann, Paul, et al.
(författare)
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An opioid system in connective tissue : A study of Achilles tendon in the rat
- 2001
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Ingår i: Journal of Histochemistry and Cytochemistry. - : SAGE Publications. - 0022-1554 .- 1551-5044. ; 49:11, s. 1387-1395
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Tidskriftsartikel (refereegranskat)abstract
- The occurrence of endogenous opioids and their receptors in rat achilles tendon was analyzed by immunohistochemistry (IHC), radioimmunoassay (RIA), and in vitro binding assays. The investigation focused on four enkephalins, dynorphin B, and nociceptin/orphanin FQ. Nerve fibers immunoreactive to all enkephalins (Met-enkephalin, Leu-enkephalin, Met-enkephalin-Arg-Gly-Lys, Met-enkephalin-Arg-Phe) were consistently found in the loose connective tissue and the paratenon, whereas dynorphin B and nociceptin/orphanin FQ could not be detected. The majority of enkephalin-positive nerve fibers exhibited varicosities predominantly seen in blood vessel walls. Measurable levels of Met-enkephalin-Arg-Phe and nociceptin/orphanin FQ were found in tendon tissue using RIA, whereas dynorphin B could not be detected. In addition to the endogenous opioids identified, delta -opioid receptors on nerve fibers were also detected by IHC. Binding assays to characterize the opioid binding sites showed that they were specific and saturable for [H-3]-naloxone (K-d 7.01 +/- 0.98 nM; B-max 23.52 +/- 2.23 fmol/mg protein). Our study demonstrates the occurrence of an opioid system in rat achilles tendon, which may be assumed to be present also in other connective tissues of the locomotor apparatus. This system may prove to be a useful target for pharmacological therapy in painful and inflammatory conditions by new drugs acting selectively in the periphery.
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| 2. |
- Aitola, M, et al.
(författare)
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Aint/Tacc3 is highly expressed in proliferating mouse tissues during development, spermatogenesis, and oogenesis
- 2003
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Ingår i: The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society. - : SAGE Publications. - 0022-1554. ; 51:4, s. 455-469
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Tidskriftsartikel (refereegranskat)abstract
- Aint was originally identified on the basis of its interaction in vitro with the aryl hydrocarbon nuclear receptor translocator (Arnt). Arnt is a common heterodimerization partner in the basic helix-loop–helix (bHLH)-PER-ARNT-SIM (PAS) protein family and is involved in diverse biological functions. These include xenobiotic metabolism, hypoxic response, and circadian rhythm. In addition, Arnt has a crucial role during development. Aint is a member of a growing family of transforming acidic coiled-coil (TACC) proteins and is the murine homologue of human TACC3. Here we report the spatiotemporal expression of Tacc3 mRNA and protein in embryonic, postnatally developing, and adult mouse tissues using in situ hybridization and immunocytochemistry. Tacc3 mRNA was highly expressed in proliferating cells of several organs during murine development. However, the only adult tissues expressing high levels were testis and ovary. Immunocytochemistry revealed that Tacc3 is a nuclear protein. Our results suggest that Tacc3 has an important role in murine development, spermatogenesis, and oogenesis.
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| 3. |
- Almqvist, PM, et al.
(författare)
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Immunohistochemical detection of nestin in pediatric brain tumors
- 2002
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Ingår i: The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society. - : SAGE Publications. - 0022-1554. ; 50:2, s. 147-158
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Tidskriftsartikel (refereegranskat)abstract
- Nestin is an intermediate filament protein (IFP) expressed in undifferentiated cells during CNS development and in CNS tumors. Previous studies have arrived at different conclusions in terms of which types of CNS tumors express nestin. In this report we establish an immunohistochemical protocol using antigen retrieval, which significantly enhances staining with two polyclonal anti-nestin antisera, #130 and #4350. The staining pattern was identical for the two nestin antisera and very similar to that of vimentin, while glial fibrillary acidic protein (GFAP), immunoreactivity was absent from 9.5-week-old forebrain. The current study of 20 primary CNS tumors from pediatric patients included seven ependymomas, seven primitive neuroectodermal tumors (PNETs), five pilocytic astrocytomas, and one glioblastoma multiforme (GBM). All these tumors expressed nestin to various extents, in contrast to five brain metastases tested. Strong nestin immunoreactivity was found in malignant primary CNS tumors, whereas benign pilocytic astrocytomas showed low but consistent nestin expression. In all tumors nestin immunoreactivity was confined to the cytoplasm of tumor cells and was co-expressed with astrocyte markers vimentin, GFAP, and S-100. Vascular endothelial cells of all neoplasms also showed marked immunoreactivity for nestin and vimentin, whereas they were negative for GFAP and S-100. In conclusion, antiserum #4350 detected nestin in formalin-fixed, paraffin-embedded tissue sections by heat-induced antigen retrieval immunohistochemistry. Nestin was expressed in both highly malignant and low malignant gliomas, indicating the potential use of nestin as a diagnostic tumor marker in surgical pathology.
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| 4. |
- Büki, Andras, 1966-, et al.
(författare)
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Novel application of tyramide signal amplification (TSA) : ultrastructural visualization of double-labeled immunofluorescent axonal profiles
- 2000
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Ingår i: Journal of Histochemistry and Cytochemistry. - : Sage Publications. - 0022-1554 .- 1551-5044. ; 48:1, s. 153-161
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Tidskriftsartikel (refereegranskat)abstract
- Fluorescent immunocytochemistry (FICC) allows multiple labeling approaches when enzyme-based techniques are difficult to combine, such as in double-labeling experiments targeting small-caliber axonal segments. Nevertheless, the conversion of FICC to a product visible at the electron microscopic (EM) level requires labor-intensive procedures, thus justifying the development of more user-friendly conversion methods. This study was initiated to simplify the conversion of FICC to EM by employing the unique properties of tyramide signal amplification (TSA), which allowed the simultaneous targeting of a fluorescent tag and biotin label to the same antigenic site. Briefly, one of two antigenic sites typically co-localized in damaged axonal segments was visualized by the application of a fluorescent secondary antibody, with the other tagged via a biotinylated antibody. Next, an ABC kit was used, followed by the simultaneous application of fluorophore-tyramide and biotin-tyramide. After temporary mounting for fluorescent digital photomicroscopy, sections were incubated in ABC and reacted with diaminobenzidine before EM analysis. Double-labeling fluorescent immunocytochemistry with TSA clearly delineated damaged axonal segments. In addition, these same axonal segments yielded high-quality EM images with discrete electron-dense reaction products, thereby providing a simple and reproducible means for following fluorescent analysis with EM.
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| 5. |
- Hultgård-Ekwall, Anna-Karin H, et al.
(författare)
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Network organization of interstitial connective tissue cells in the human endolymphatic duct
- 2003
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Ingår i: Journal of Histochemistry and Cytochemistry. - : SAGE Publications. - 0022-1554 .- 1551-5044. ; 51:11, s. 1491-500
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Tidskriftsartikel (refereegranskat)abstract
- The human endolymphatic duct (ED) and sac of the inner ear have been suggested to control endolymph volume and pressure. However, the physiological mechanisms for these processes remain obscure. We investigated the organization of the periductal interstitial connective tissue cells and extracellular matrix (ECM) in four freshly fixed human EDs by transmission electron microscopy and by immunohistochemistry. The unique surgical material allowed a greatly improved structural and epitopic preservation of tissue. Periductal connective tissue cells formed frequent intercellular contacts and focally occurring electron-dense contacts to ECM structures, creating a complex tissue network. The connective tissue cells also formed contacts with the basal lamina of the ED epithelium and the bone matrix, connecting the ED with the surrounding bone of the vestibular aqueduct. The interstitial connective tissue cells were non-endothelial and non-smooth muscle fibroblastoid cells. We suggest that the ED tissue network forms a functional mechanical entity that takes part in the control of inner ear fluid pressure and endolymph resorption.
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| 6. |
- Lang, P, et al.
(författare)
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Expression and distribution of tartrate-resistant purple acid phosphatase in the rat nervous system
- 2001
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Ingår i: The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society. - : SAGE Publications. - 0022-1554. ; 49:3, s. 379-396
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Tidskriftsartikel (refereegranskat)abstract
- Tartrate-resistant purple acid phosphatase (TRAP) of osteoclasts and certain cells of the monocyte–macrophage lineage belongs to the family of purple acid phosphatases (PAPs). We provide here evidence for TRAP/PAP expression in the central and peripheral nervous systems in the rat. TRAP/PAP protein was partially purified and characterized from the trigeminal ganglion, brain, and spinal cord. The TRAP activity (U/mg tissue) in these tissues was about 10–20 times lower than in bone. Reducing agents, e.g. ascorbate and ferric iron, increased the TRAP activity from the neural tissues (nTRAP) and addition of oxidizing agents completely inactivated both bone and nTRAP. The IC50 for three known oxyanion inhibitors of TRAP/PAP was similar for bone and nTRAP with the same rank order of potency (molybdate > tungstate > phosphate). This indicates that the redox-sensitive binuclear iron center characteristic of mammalian PAPs is present also in nTRAP. Western blots of partially purified nTRAP revealed a band with the expected size of 35 kD. The expression of TRAP in the trigeminal ganglion, brain, and spinal cord was confirmed at the mRNA level by RT-PCR. In situ hybridization histochemistry demonstrated TRAP mRNA expression in small ganglion cells of the trigeminal ganglion, in α-motor neurons of the ventral spinal cord, and in Purkinje cells of the cerebellum. TRAP-like immunoreactivity was encountered in the cytoplasm of neuronal cell bodies in specific areas of both the central and the peripheral nervous system. Together, the data demonstrate that active TRAP/PAP is expressed in certain parts of the rat nervous system.
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| 7. |
- Liu, Jing-Xia, et al.
(författare)
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Muscle spindles in the deep muscles of the human neck : a morphological and immunocytochemical study
- 2003
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Ingår i: Journal of Histochemistry and Cytochemistry. - : Sage Publications. - 0022-1554 .- 1551-5044. ; 51:2, s. 175-186
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Tidskriftsartikel (refereegranskat)abstract
- Muscle spindle density is extremely high in the deep muscles of the human neck. However, there is a paucity of information regarding the morphology and immunoreactivity of these muscle spindles. The objective of this study was to investigate the intrafusal fiber content and to assess the myosin heavy chain (MyHC) composition of muscle spindles from human deep neck muscles. In addition to the conventional spindles containing bag(1), bag(2), and chain fibers (b(1)b(2)c spindle), we observed a number of spindles lacking bag(1) (b(2)c spindle) or bag(2) (b(1)c spindle) fibers. Both bag(1) and bag(2) fibers contained slow tonic MyHCs along their entire fiber length and MyHCI, MyHCIIa, embryonic, and alpha-cardiac MyHC isoforms along a variable length of the fibers. Fetal MyHC was present in bag(2) fibers but not in bag(1) fibers. Nuclear chain fibers contained MyHCIIa, embryonic, and fetal isoforms with regional variations. We also compared the present data with our previous results obtained from muscle spindles in human biceps brachii and the first lumbrical muscles. The allotment of numbers of intrafusal fibers and the MyHC composition showed some muscle-related differences, suggesting functional specialization in the control of movement among different human muscles.
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| 8. |
- Lopez-Cepero, Jose M
(författare)
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Silver carbonate staining reveals mitochondrial heterogeneity
- 2004
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Ingår i: Journal of Histochemistry and Cytochemistry. - 0022-1554 .- 1551-5044. ; 52:2, s. 211-216
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Tidskriftsartikel (refereegranskat)abstract
- Silver staining methods, when selective, yield a high-contrast and high-resolution image in optical microscopy. A classical method for silver impregnation of mitochondria has been applied to murine tissues and reveals a marked heterogeneity among mitochondria in single cells. This heterogeneity can be detected in the optical microscope but is even more evident at the ultrastructural level. The differences in staining intensity may reflect different stages in the mitochondrial life cycle. The progressive accumulation of uranyl-argyrophilic material may be a marker of mitochondrial aging. This highly selective staining procedure may be of use in studies of mitochondrial changes under pathological conditions and during apoptosis.
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| 9. |
- Pedrosa-Domellöf, Fatima, et al.
(författare)
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Laminin chains in developing and adult human myotendinous junctions.
- 2000
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Ingår i: Journal of Histochemistry and Cytochemistry. - 0022-1554 .- 1551-5044. ; 48:2, s. 201-10
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Tidskriftsartikel (refereegranskat)abstract
- In addition to being the specialized site for transmission of force from the muscle to the tendon, the myotendinous junction (MTJ) also plays an important role in muscle splitting during morphogenesis. An early event in the formation of the MTJ is a regional deposition of basement membranes. We used immunocytochemistry to investigate the distribution of laminin chains during the development of MTJs in human limb muscle at 8-22 weeks of gestation (wg) and in adult MTJs. We used polyclonal antibodies and a new monoclonal antibody (MAb) against the human laminin alpha1 G4/G5 domains. At 8-10 wg, laminin alpha1 and laminin alpha5 chains were specifically localized to the MTJ. Laminin alpha1 chain remained restricted to the MTJ at 22 wg as the laminin beta2 chain had appeared, whereas the laminin alpha5 chain became deposited along the entire length of the myotubes from 12 wg. In the adult MTJ, only vestigial amounts of laminin alpha1 and laminin alpha5 chains could be detected. On the basis of co-distribution data, we speculate that laminin alpha1 chain in the forming MTJ undergoes an isoform switch from laminin 1 to laminin 3. Our data indicate a potentially important role for laminin alpha1 chain in skeletal muscle formation.
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| 10. |
- Petersson, Christoffer, 1973-, et al.
(författare)
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A new method to visualize the helicobacter pylori-associated lewisb-binding adhesin utilizing SDS-digested freeze-fracture replica labeling
- 2000
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Ingår i: Journal of Histochemistry and Cytochemistry. - : SAGE Publications. - 0022-1554 .- 1551-5044. ; 48:6, s. 877-883
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Tidskriftsartikel (refereegranskat)abstract
- Freeze-fracture replica labeling has become a versatile tool to visualize both membrane components and other cell structures using SDS-replica cleaning before specific immunogold labeling of proteins or lipids. We report here for the first time the adoption and optimization of the method to studies of bacterial envelopes, as applied to structural analysis of the distribution of the unique BabA-adhesin of the gastric pathogen Helicobacter pylori. BabA is important for bacterial adherence to the human epithelial cell lining of the stomach. The adhesin was found to be distributed all over the bacterial cell surfaces. Our results suggest that the SDS-replica labeling allows assessment of protein localization to distinct cell compartments and analysis of co-localization with neighboring membrane structures.
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