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J A Matsubara

Publications and source records attributed to J A Matsubara.

At least 19 recordsLinked to original sources
PubMed2006

Stage specificity of novel growth factor expression during development of proliferative vitreoretinopathy.

OBJECTIVE: To compare the relative levels of connective tissue growth factor (CTGF), platelet-derived growth factor alpha (PDGF-AA), and hepatocyte growth factor (HGF) in glial and retinal pigment epithelial (RPE) cells of epiretinal membranes from proliferative vitreoretinopathy (PVR). METHODS: A total of 37 PVR membranes, of various stages, underwent fluorescent immunohistochemisty and confocal laser scanning microscopy to localize CTGF, HGF, and PDGF-AA in RPE and glial cells. RESULTS: Numerous RPE, and relatively fewer glial cells, were found in all stages of PVR. CTGF immunoreactivity increased from early to late stage PVR and was principally expressed by RPE cells in early stage, and by glial cells in late stage PVR. HGF, expressed by both RPE and glial cells, was principally expressed in mid-stage PVR. PDGF-AA, expressed by both cell types, demonstrated a uniform level of staining throughout all stages of PVR. CONCLUSIONS: RPE and glial cells contribute to the expression of CTGF, HGF, and PDGF-AA during PVR, but with specific developmental patterns. PDGF-AA is expressed uniformly throughout all stages of PVR, while HGF expression peaks during mid stage, and CTGF expression is highest during late stage PVR. These results allow for the development of stage-specific therapeutics for PVR that may allow targeting of the early proliferative and/or the late tractional stages of PVR.

Biomarkers↗
PubMed2005

Vitreous leptin levels in retinal disease.

BACKGROUND/AIMS: The purpose of this study was to investigate the relationship between vitreous leptin levels and retinal diseases. METHODS: Levels of vitreous leptin were evaluated in proliferative diabetic retinopathy (PDR) and a variety of other retinopathies including: macular disease, neovascular maculopathies, primary retinal detachments, and vascular occlusive disease. RESULTS: In patients with PDR (N=7), the average vitreous level of leptin (37.4 ng/ml) was significantly higher than that in patients with PVR (<1.0 ng/ml, P<0.05). Vitreous leptin level in patients with PVR or macular disease (N=18), with or without diabetes, was not significantly different from the control subjects who had retinal detachment only (N=7). CONCLUSION: The results show that the leptin level in vitreous taps is elevated in PDR. We suggest that leptin plays an active role in PDR.

Adult↗
PubMed2002

Immunohistochemical investigations of neurofilament M' and alphabeta-crystallin in the magnocellular layers of the primate lateral geniculate nucleus.

The magnocellular and parvocellular pathways are two major processing streams in the primate visual system. Using high-density grid arrayed cDNA clones to hybridize to cDNA probes from cortical regions of each pathway, a list of candidate differentially expressed genes was produced [Mol. Brain Res. 82 (2000) 11-24]. Magnocellular pathway candidates include neurofilament M' and alphabeta-crystallin. Using antibodies generated against these proteins, immunohistochemical analysis revealed preferential staining of the magnocellular layers in the primate lateral geniculate nucleus, providing verification of two candidate magnocellular-enriched genes.

Animals↗
PubMed2001

The role of leptin in choroidal neovascularization.

PURPOSE: The purpose of this study was to investigate the role of leptin in choroidal neovascularization. METHODS: We examined the localization of leptin by immunohistochemistry in nine choroidal neovascular membranes surgically excised from patients with age-related macular degeneration, idiopathic choroidal neovascularization, and ocular histoplasmosis. Controls included omission of primary antibody, use of an irrelevant primary antibody and leptin staining of posterior segment of four normal donor eyes. RESULTS: Leptin was present in eight membranes and appeared vesicular, within the cytoplasm. The more vascular membranes and those consisting of a larger number of retinal pigment epithelium cells were associated with greater leptin staining. Leptin was not seen in the posterior segment of the four normal eyes. CONCLUSION: We suggest that leptin plays an active role in choroidal neovascularization, although further experiments are necessary to establish a causal relationship.

Adolescent↗
PubMed2001

The effects of panretinal photocoagulation on the primary visual cortex of the adult monkey.

PURPOSE: To determine the effects of panretinal photocoagulation (PRP) on the levels of cytochrome oxidase (CO), Zif268, synaptophysin, and growth-associated protein 43 (GAP-43) in the primary visual cortex of adult monkeys. METHODS: Ten adult primates underwent unilateral argon laser PRP with instrument settings at 300 to 500 microns spot diameter, 200 to 500 mW power intensity, and 0.1 to 0.2 second duration, causing moderate to severe burns in the peripheral retina. At 20 hours, 12 days, 6 months, and 13 months after laser treatment, the visual cortex was assessed histologically for CO and immunohistochemically for Zif268, synaptophysin, and GAP-43. RESULTS: PRP resulted in transneuronal changes in the relative distributions of CO, Zif268, synaptophysin, and GAP-43 in the primary visual cortex. CO activity was relatively decreased in the lasered eye's ocular dominance columns at 12 days post-PRP, with recovery by 13 months post-PRP. The level of Zif268 was dramatically decreased in the lasered eye's ocular dominance columns at 20 hours post-PRP, with gradual recovery by 13 months post-PRP. Levels of synaptophysin and GAP-43 immunoreactivity were increased in both the lasered and the nonlasered eyes' ocular dominance columns at 6 months post-PRP. CONCLUSION: PRP treatment results in metabolic activity changes in the visual cortex of the adult monkey. These changes are followed chronologically by spatial redistribution of synaptophysin and GAP-43, neurochemicals known to play a role in cortical plasticity. This study demonstrates, for the first time, that PRP as used in the treatment of diabetic retinopathy results in a redistribution of neurochemicals in the adult monkey visual cortex. Such changes may help explain the anomalous visual functional loss often reported by patients after PRP.

Animals↗
PubMed2000

Organization of efferent neurons in area 19: the projection to extrastriate area 21a.

The organization of efferent neurons in area 19 of the cat was examined by bulk injections of retrograde tracers, WGA-HRP and CTX-Au, into extrastriate area 21a. In one case, the cortex was cut coronally and retrogradely labeled cells in area 19 were present in columnar register throughout layers 2 to 6, with the majority of labeled cells in layers 2/3. The number of columns per tissue section ranged from 0 to 4 and had a centre-to-centre spacing ranging from 0.6 to 0.9 mm. A few lightly labeled cells were found between the columns. In six other cases, the visual cortex was flattened, and cut in the tangential plane to reveal a pattern of irregular, widely spaced bands that were elongated in the mediolateral direction with a mean centre-to-centre spacing of 2.6 mm. The density of labeled cells within these bands fluctuated such that dense aggregates of cells were found, on average, at 0.9 mm intervals along the bands. This tangential heterogeneity in density, along with the patchy columnar staining witnessed in the coronal plane, suggests that the widely spaced efferent projection bands may have a patchy substructure with a spacing of approximately 1 mm. The pattern of efferent projection bands and its substructure in area 19 is reminiscent of the stripe-like organization of V2 found in primates.

Animals↗
PubMed2000

The projection from V1 to extrastriate area 21a: a second patchy efferent pathway colocalizes with the CO blob columns in cat visual cortex.

The different patchy organizations of neurons projecting from primary visual cortex (area 17) to the various extrastriate areas may contribute to functional differences in the output to each of these areas. The pattern of neurons projecting to extrastriate area 21a was examined using large injections of retrograde tracers and compared to the pattern shown by neurons projecting to the lateral suprasylvian area (LS). Patches of neurons projecting to 21a showed a bimodal laminar distribution, with numerous labeled cells in the upper and lower third of layer 3 bracketing a sparsely labeled central third; LS-projecting neurons were confined to the lower and middle thirds of layer 3. The 21a projecting cells were relatively tighter in their clustering pattern than the LS projecting cells, i. e. the difference in labeling density between patch and interpatch zones was greater for 21a-projecting cells than for LS-projecting cells. As previously shown for the LS-projecting cells, patches of 21a-projecting cells colocalized with CO blob columns in area 17. Combined with our earlier results, this study shows that the CO blob compartments in area 17 give rise to at least two distinct efferent pathways, one projecting to LS and the other to 21a, and furthermore suggest that each pathway may carry unique information to its extrastriate target.

Animals↗
PubMed1999

Experimental gene therapy for an in vitro model of proliferative vitreoretinopathy.

BACKGROUND: Proliferative vitreoretinopathy (PVR) is the leading cause of failure of retinal reattachment surgery. Since a key component of PVR is cell proliferation, we performed a study to examine whether the ribonucleotide-reductase-deficient herpes simplex virus type I (HSV-I) mutant hrR3 can be effective at destroying proliferating retinal pigment epithelial (RPE) cells and thus prevent epiretinal membrane formation and PVR, while sparing nondividing cells, such as neurons. METHODS: Primary cultures of rat RPE cells and rat cortical neurons were infected with 300 microL of hrR3 HSV-I to achieve a multiplicity of infection of 1.0. After 1 hour at 37 degrees C, 700 microL of growth medium was added to raise the total volume of medium to 1 mL. At 0, 12, 24 and 36 hours the cultures were observed, and the ratio of dead cells to live cells was determined. HSV infection and protein expression were confirmed by a beta-galactosidase histochemical assay or an antihuman HSV-I immunoassay, or both. RESULTS: At 24 hours more than 95% of the RPE cells and neurons stained positively for HSV infection, although beta-galactosidase was expressed predominantly in RPE cells. At 36 hours 72% (standard deviation 2.1%) of the RPE cells were dead. There was no noticeable cell death in the neuronal or mock-infected control cultures. INTERPRETATION: The results suggest that the hrR3 mutant strain of HSV-I can be used to infect and selectively kill actively proliferating rat RPE cells while sparing normal, nonreplicating cells. This model may be used to explore potential therapies for PVR in humans.

Animals↗
PubMed1996

Comparative morphology of three types of projection-identified pyramidal neurons in the superficial layers of cat visual cortex.

The morphology and dendritic organization of corticocortical neurons in the superficial layers of area 18 that project to area 17 were studied by intracellular injection of lucifer yellow in the fixed-slice preparation. This corticocortical population contains primarily standard pyramidal cells, but occasional nonpyramidal, modified, fusiform, star, and inverted pyramidal cells were also seen. All cell types were present throughout layer 2 and in the upper and middle parts of layer 3. Standard pyramidal cells were found exclusively in lower layer 3. The mean somatic area of the area 17 projecting neurons was 251 microns 2. The width of basal dendritic fields was correlated to cell size for standard pyramidal cells but not for the other cell types. Next, the morphology and dendritic organization of the area 17 projecting neurons were compared to the pyramidal cells of the local horizontal patch networks and of the callosal system. The depth profile of the area 17 projecting and callosal pyramidal groups was virtually identical, peaking at 400 microns from the pial surface, whereas the local patch pyramidal group peaked at 281 microns. The local patch, area 17 projecting, and callosal pyramidal cells displayed increasingly larger mean somatic areas and basilar dendritic field width measurements. The number of basal dendritic branch points was greatest for callosal cells, and it was indistinguishable between local patch and area 17 projecting neurons. In the tangential plane, circular dendritic fields were observed on all callosal cells, but they were found on only approximately half of the local patch and area 17 projecting neurons. The remaining local patch and area 17 projecting neurons displayed mediolaterally and anteroposteriorly elongated basal dendritic fields, respectively.

Animals↗
PubMed1996

Laminar and columnar patterns of geniculocortical projections in the cat: relationship to cytochrome oxidase.

We examined the laminar and columnar arrangement of projections from different layers of the lateral geniculate nucleus (LGN) to the visual cortex in the cat. In light of recent reports that cytochrome oxidase blobs (which in primates receive specific geniculate inputs) are also found in the visual cortex of cats, the relationship between cytochrome oxidase staining and geniculate inputs in this species was studied. Injections of wheat germ agglutinin-conjugated horseradish peroxidase were made into the anterior "genu" of the LGN, where isoelevation contours of the geniculate layers are distorted due to the curvature of the nucleus. Consequently, anterograde labeling from the various LGN layers was topographically separated across the surface of the cortex, and labeling in a particular isoelevation representation of the cortex could be associated with a specific layer of the LGN. Labeling from the A layers, which contain X and Y cells, was coextensive with layers 4 and 6 in both area 17 and area 18, as previously reported. Labeling from the C layers, which contain Y and W cells, occupied a zone extending from the 4a/4b border to part way into layer 3 in area 17. The labeling extended throughout layer 4 in area 18. There was also labeling in layer 5a and layer 1 in both area 17 and area 18. Except in layer 1, labeling from the C layers was patchy. In the tangential plane, adjacent sections stained for cytochrome oxidase showed that the patches of labeling from the C laminae aligned with the cytochrome oxidase blobs. The cytochrome blobs were visible in layers 3 and 4a, but not in layer 4b in both areas 17 and 18. These results suggest that W cells project specifically to the layer 3 portion of the blobs, while Y cells, at least those of the C layers, project specifically to the layer 4a portion of the blobs in area 17. The heavy synaptic drive of the Y cells is probably the cause of the elevated metabolism, and thus, higher cytochrome oxidase activity, of the blobs.

Animals↗
PubMed1996

Differential expression of neurofilament protein in the visual system of the vervet monkey.

It has been previously reported that the monoclonal antibody SMI-32 reveals a characteristic pattern of immunostaining which may be used to delineate various cortical modules in the monkey visual system. We wished to examine staining patterns with this antibody at both the lateral geniculate nucleus (LGN) and cortical levels with regard to magno- and parvocellular processing schemes in the vervet monkey. Using standard immunohistochemical procedures, we have found that the M-layers of the LGN were intensely stained in comparison to P-layers and that there were regional variations in staining within the visual cortex that reflected this input. The transition between areas V1 and V2 was especially prominent due to differences in the laminar staining profiles. Another striking result was found within the superior temporal sulcus where heavy SMI-32 immunostaining confined to the floor of the sulcus coincided with a similar zone of intense myelin staining. We have also found a number of other areas within the intraparietal and lateral sulci that show foci of heavy SMI-32 staining. As with Cat-301 immunostaining, the regional variabilities that are observed with SMI-32 in the visual cortex reflect molecular distinctions that may provide further criteria for functional segmentation.

Animals↗
PubMed1992

Presence of GABA-immunoreactive neurons within intracortical patches in area 18 of the cat.

In cat visual cortex, horizontal, intracortical connections spread laterally to link together specific columnar sites. When visualized by retrograde tracers, these intracortical connections appear as periodic, columnar patches of dense cellular labeling interspersed with areas of much less dense labeling. We looked for anatomical evidence for direct inhibition among the patchy, horizontal connections in area 18, by combining retrograde labeling using wheat germ agglutinin (WGA) conjugated to horseradish peroxidase (HRP) with immunohistochemistry using an antiserum against the inhibitory neurotransmitter gamma-amino butyric acid (GABA). We found numerous double-labeled cells associated with some, but not all, of the local patches nearest to the injection site. In the superficial layers, the GABA-immunoreactive cells also labeled with WGA-HRP were confined to a zone approximately 1.0 mm from the center of the injection, while the double-labeled cells in the deeper layers spanned greater distances, up to 3.0 mm from the injection center. These more distant, double-labeled cells in the deeper layers were located on the edges or outside of the patches of dense labeling. Thus, all of the more distant intracortical patches, as well as some of the more proximal patches were devoid of double-labeled cells--a finding which suggests that direct inhibition may occur among only a selected group of the 'short range' intracortical patches and among none of the long-range patches.

Animals↗
PubMed1990

Light and electron microscopical studies on the spherical neurons in the electrosensory lateral line lobe of the gymnotiform fish, Sternopygus.

Spherical cells are a principal cell type of the electrosensory lateral line lobe (ELLL) and play a crucial role in the jamming avoidance response (JAR) behavior. Since Sternopygus, a low frequency gymnotiform genus, does not display a JAR we searched for spherical cells in its ELLL. While present in Sternopygus, spherical cells differed remarkedly from those in the high-frequency gymnotiforms, Eigenmannia and Apteronotus. This study reveals species-characteristic differences in the morphology and synaptology of the spherical cell, a projection neuron located in the deep neuropil layer (DNL) of the ELLL. In contrast to the adendritic spherical cell of other species, the spherical neuron in Sternopygus exhibits an extensive basilar dendrite that extends into the primary electroreceptive afferent zone, the deep fiber layer (DFL). In Sternopygus, these neurons are distributed evenly across the full length of each tuberous subdivision, with cell densities highest in the centrolateral subdivision. At the ultrastructural level, the contacts on the soma, proximal, and distal dendrite of the spherical neuron in Sternopygus are asymmetrical chemical synapses, quite distinct from the electrotonic gap junctions found on the spherical neurons of other species.

Animals↗
PubMed1990

Calbindin D-28K immunoreactivity in the cat's superior olivary complex.

The calcium binding protein, calbindin D-28K (CaBP), was identified immunohistochemically in the cat's superior olivary nuclei. Intense somatic labeling was observed in the medial and lateral nucleus of the trapezoid body. The lateral superior olive contained dense, perisomatic, terminal bouton labeling surrounding unlabeled somata, while the medial superior olive exhibited the least amount of labeling, comprised only of a few fiber fragments.

Animals↗
PubMed1988

Intracortical connections and their physiological correlates in the primary auditory cortex (AI) of the cat.

We studied the functional and anatomical properties of the intrinsic connections in the primary auditory cortex (AI) of the cat by using physiological mapping and retrograde tracing methods. Our results revealed that a focal microinjection of tracer labeled as many as five intracortical patches in AI. The patches contained labeled pyramidal and non-pyramidal cell types, most of which were clustered in the middle layers. A densely distributed anterograde-like reaction product was present in the superficial layers above the labeled cells. The distribution of the patches was anisotropic, with most patches occurring dorsal, ventral, and anterior to the injection site. We examined the correlation between the characteristic frequency (CF) and binaural response properties of the injected and labeled regions. We found local labeling in regions possessing CFs equivalent to or slightly greater than that of the injected area. This appears to be a specific connection since we were able to predict the general location of many of the patches on the basis of the organization of the isofrequency domains. Patches were more numerous dorsoposterior to the injection site when the isofrequency contours ran obliquely (i.e., dorsoposterior to ventroanterior) across AI. The binaural response properties of the injected and labelled regions, however, were unrelated.

Animals↗
PubMed1987

Laminar distribution of GABA-immunoreactive neurons and processes in area 18 of the cat.

Intracortical inhibition mediated by the neurotransmitter gamma-amino butyric acid (GABA) plays a crucial role in the formation of the physiological response properties of neurons in mammalian visual cortex. Using a potent antibody developed against the amino acid neurotransmitter. GABA (Immunoclear Co., USA), we have identified GABA-immunoreactive neuronal somata and processes in area 18 of the cat. The GABA-positive neurons included multipolar, bipolar and bitufted but not pyramidal cell types. The density of GABA-immunoreactive neurons was higher in Layers I-IV (range 182-205 cells/mm2) than in Layers V-VI (range 78-92 cells/mm2). The mean areal measurement of GABA-immunoreactive somatic profiles was 135 micron2 (s.d. = 66). We observed numerous GABA-immunoreactive fiber fragments predominantly in Layers I, III, IV and V. Most of the fibers were oriented with their long axis tangential to the cortical surface, but, vertically-oriented fibers were observed as well. Many of the fibers were axonal-like and appeared beaded in Layer I and occasionally in II, while most of the fibers in the other layers appeared myelinated. A dense GABA-immunoreactive neuropil was present in Layer V. Results from our studies provide immunohistochemical evidence for a system of GABA-immunoreactive neurons and axonal collaterals which presumably mediate inhibition in the visual cortex. Since many of the GABA-immunoreactive fibers were oriented tangential to the cortical surface, the structural elements required for inhibition between functional columns are present. GABA-mediated inhibition both within and between functional columns likely assists in the formation of receptive field properties in the visual cortex.

Animals↗
PubMed1987

Anatomical properties and physiological correlates of the intrinsic connections in cat area 18.

After making a map of response properties of neurons in a roughly 3 X 4 mm region of area 18 in the cat, we injected wheat-germ agglutinin horseradish peroxidase (WGA-HRP) and succinylated concanavalin A (Con A) into physiologically identified regions of the map. We observed up to 10 patches of retrogradely labeled cells surrounding each injection site. The majority of the patches occurred within 1.4 mm of the center of the injection site, but rare patches were found as far as 3.4 mm from the injection site. The mean center-to-center spacing of the intrinsic patches was about 1 mm, while the mean distance between the center of the injection site and the nearest patches was less than 1 mm. The labeled cells included both nonpyramidal and pyramidal types and were found in all layers, although they were usually most dense in layers II-IV. Between 2% and 9% of the cells within a cortical column were labeled after a single injection of WGA-HRP or Con A into area 18. Injections of different tracers into 2 neighboring areas resulted in a uniform and less patchy distribution of labeled cells, which suggests that the patches observed after a single injection were only a portion of a continuous horizontal system of interconnections. The patterns and positions of the intrinsic patches were compared to the distribution of the following receptive-field properties: preferred orientation, receptive-field location, and eye preference. The preferred orientations of the recording sites within the injected and labeled areas were different and, most frequently, orthogonal to each other. This is a highly specific projection, since regions with orientation values like those of the injection site were "within range," yet not labeled. We were unable to detect any relationship between the ocular preferences of the injected and labeled cell regions. Injections into areas predominantly driven by the contralateral eye resulted in labeled regions exhibiting varied eye preference distributions. In some animals they were like the injection site and in others there were equal numbers of contra- and ipsilateral eye-dominated regions. The overall distribution of the patches around the injection site was elongated along the anterior-posterior cortical axis of the brain. The patches extended further in the posterior than the anterior direction. These observations appear to be related to the finding that the cortical magnification factor is greater along the anterior-posterior than the medial-lateral axis of area 18.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗