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1.
Clin Radiol ; 75(3): 209-215, 2020 03.
Article in English | MEDLINE | ID: mdl-31785782

ABSTRACT

AIM: To evaluate the capability of integrated 2-[18F]-fluoro-2-deoxy-d-glucose (FDG)-positron-emission tomography (PET)/magnetic resonance imaging (MRI) to characterise the distinct phenotypes of endometrial cancer. MATERIALS AND METHODS: Thirty-one patients with endometrial cancer (23 with type I, including 17 G1 and six G2 endometrioid adenocarcinomas, and eight with type II, including three G3 endometrioid adenocarcinomas, two carcinosarcomas, and three serous carcinomas) underwent pretreatment FDG-PET/MRI with simultaneous reduced field-of-view diffusion-weighted imaging (DWI). The standardised uptake value (SUV), apparent diffusion coefficient (ADC), and SUV-to-ADC ratio were compared between low-risk (type I and stage I and negative for lymph-vascular space invasion [LVSI]) and high-risk cancers. The diagnostic accuracy for discriminating the cancer phenotypes was evaluated using receiver operating characteristic (ROC) analysis. RESULTS: The SUV was not significantly different between low-risk and high-risk endometrial cancers. High-risk cancers had a significantly lower ADC (756±232×10-6) and a greater SUV-to-ADC ratio (21.7±7.7×109) than low-risk cancers (937±154×10-6, p<0.05 and 13.1±4.1×109, p<0.005, respectively). On comparison of the area under the ROC curves (AUCs), the SUV-to-ADC ratio demonstrated the greatest diagnostic accuracy (ratio 0.83, ADC 0.72, and SUV 0.66). The AUCs for the ratios were significantly higher than those for the SUV values (p<0.05). The optimal SUV-to-ADC cut-off value of 16.9×109 for predicting high-risk cancer revealed a sensitivity of 73%, specificity of 81%, and accuracy of 77%, which was significantly higher than the accuracy for SUV. CONCLUSION: The SUV-to-ADC ratio obtained using integrated FDG-PET/MRI with high-resolution DWI reflects tumour aggressiveness including LVSI, and will be useful for lesion characterisation to decide on an appropriate therapeutic strategy for endometrial cancer.


Subject(s)
Endometrial Neoplasms/diagnostic imaging , Multimodal Imaging , Diffusion Magnetic Resonance Imaging , Female , Fluorodeoxyglucose F18 , Humans , Middle Aged , Neoplasm Grading , Phenotype , Positron-Emission Tomography , Radiopharmaceuticals , Retrospective Studies
2.
Cytopathology ; 29(4): 361-367, 2018 08.
Article in English | MEDLINE | ID: mdl-29768678

ABSTRACT

INTRODUCTION: The aims of the Fukui Cervical Cancer Screening (FCCS) study are to determine the frequency of women with high-risk HPV (hrHPV), whether HPV16 or HPV18 (HPV16/18), in the Japanese cancer screening population for the first time and to identify the best strategy for cervical cancer screening in Japan. METHODS: This study enrolled 7584 women aged ≥25 years who were undergoing routine screening. All women underwent LBC and cobas HPV tests. Women with abnormal cytology, whether hrHPV positive or negative; women with hrHPV positivity with either normal or abnormal cytology; and women randomly selected from women with normal cytology and negative hrHPV negative were referred for colposcopy. RESULTS: The prevalences of hrHPV positivity and HPV16/18 positivity were 6.8% and 1.7%, respectively. The baseline data from the FCCS study showed that the combination of HPV tests and cytology was more sensitive than cytology with respect to the detection of intraepithelial neoplasia grade 2 or worse. However, the specificity (94.1%) of the co-testing strategy that required all women with abnormal cytology or hrHPV positivity to be referred for colposcopy was much lower than that (97.8%) of cytology. The sensitivity and specificity of the co-testing strategy that required only women with abnormal cytology or HPV16/18 positivity to undergo colposcopy were 85.5% and 97.0%, respectively. CONCLUSION: The baseline data from the FCCS study suggest that a cervical cancer screening strategy in which only women with abnormal cytology or HPV16/18 positivity undergo colposcopy offers a more balanced sensitivity and specificity than other strategies.


Subject(s)
Early Detection of Cancer/methods , Human papillomavirus 16/isolation & purification , Human papillomavirus 18/isolation & purification , Mass Screening/methods , Papillomavirus Infections/pathology , Uterine Cervical Neoplasms/pathology , Adult , Aged , Colposcopy , Female , Flow Cytometry , Humans , Japan , Middle Aged , Papillomavirus Infections/virology , Sensitivity and Specificity , Uterine Cervical Neoplasms/virology
3.
J Neurophysiol ; 107(4): 1094-110, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22114163

ABSTRACT

We used dynamic dense noise stimuli and local spectral reverse correlation methods to reveal the local sensitivities of neurons in visual area 2 (V2) of macaque monkeys to orientation and spatial frequency within their receptive fields. This minimized the potentially confounding assumptions that are inherent in stimulus selections. The majority of neurons exhibited a relatively high degree of homogeneity for the preferred orientations and spatial frequencies in the spatial matrix of facilitatory subfields. However, about 20% of all neurons showed maximum orientation differences between neighboring subfields that were greater than 25 deg. The neurons preferring horizontal or vertical orientations showed less inhomogeneity in space than the neurons preferring oblique orientations. Over 50% of all units also exhibited suppressive profiles, and those were more heterogeneous than facilitatory profiles. The preferred orientation and spatial frequency of suppressive profiles differed substantially from those of facilitatory profiles, and the neurons with suppressive subfields had greater orientation selectivity than those without suppressive subfields. The peak suppression occurred with longer delays than the peak facilitation. These results suggest that the receptive field profiles of the majority of V2 neurons reflect the orderly convergence of V1 inputs over space, but that a subset of V2 neurons exhibit more complex response profiles having both suppressive and facilitatory subfields. These V2 neurons with heterogeneous subfield profiles could play an important role in the initial processing of complex stimulus features.


Subject(s)
Orientation/physiology , Sensory Receptor Cells/physiology , Space Perception/physiology , Visual Cortex/cytology , Visual Fields/physiology , Action Potentials/physiology , Animals , Anisotropy , Brain Mapping , Macaca mulatta/physiology , Nonlinear Dynamics , Photic Stimulation/methods , Psychophysics , Reaction Time , Sensory Gating/physiology , Spectrum Analysis , Statistics as Topic , Visual Cortex/physiology
4.
Cereb Cortex ; 21(9): 2033-45, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21263036

ABSTRACT

Amblyopia, a developmental disorder of spatial vision, is thought to result from a cascade of cortical deficits over several processing stages beginning at the primary visual cortex (V1). However, beyond V1, little is known about how cortical development limits the visual performance of amblyopic primates. We quantitatively analyzed the monocular and binocular responses of V1 and V2 neurons in a group of strabismic monkeys exhibiting varying depths of amblyopia. Unlike in V1, the relative effectiveness of the affected eye to drive V2 neurons was drastically reduced in the amblyopic monkeys. The spatial resolution and the orientation bias of V2, but not V1, neurons were subnormal for the affected eyes. Binocular suppression was robust in both cortical areas, and the magnitude of suppression in individual monkeys was correlated with the depth of their amblyopia. These results suggest that the reduced functional connections beyond V1 and the subnormal spatial filter properties of V2 neurons might have substantially limited the sensitivity of the amblyopic eyes and that interocular suppression was likely to have played a key role in the observed alterations of V2 responses and the emergence of amblyopia.


Subject(s)
Amblyopia/physiopathology , Strabismus/physiopathology , Visual Cortex/physiopathology , Age of Onset , Algorithms , Animals , Contrast Sensitivity/physiology , Data Interpretation, Statistical , Dominance, Ocular/physiology , Macaca mulatta , Microelectrodes , Neurons/physiology , Normal Distribution , Orientation/physiology , Photic Stimulation , Refractive Errors/physiopathology , Vision, Binocular/physiology , Visual Cortex/cytology , Visual Fields/physiology
5.
Clin Exp Immunol ; 160(3): 394-402, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20089076

ABSTRACT

Interstitial lung disease (ILD) is an intractable disease induced by various factors in humans. However, there is no universally effective treatment for ILD. In this study, we investigated the role of transforming growth factor (TGF)-beta signalling in the pathogenesis of ILD by using model mice. Injection of interleukin (IL)-18 plus IL-2 in C57BL6 (B6) mice resulted in acute ILD by infiltration of natural killer (NK) cells and a significant increase of TGF-beta mRNA in the lung. To examine the pathogenetic role of TGF-beta in ILD mice, we used SB-431542 (4-[4-(1,3-benzodioxol-5-yl)-5-(2-pyridinyl)-1H-imidazol-2-yl]-benzamide), which is a potent and selective inhibitor of TGF-beta receptor I (TbetaRI), also known as activin receptor-like kinase 5 (ALK5). Treatment of B6-ILD mice with SB-431542 resulted in improvement of ILD, delay in mortality, reduction of the expression of interferon (IFN)-gamma and IL-6 in the lungs. The same treatment also decreased significantly the percentage of natural killer (NK) cells in the lungs (P < 0.05) and mRNA expression levels of certain chemokines such as CCL2, CCL3, CCL4, CCL5 and CXCL10 in B6-ILD. These findings were confirmed by IL-18 plus IL-2 treatment of Smad3-deficient (Smad3(-/-)) mice (P < 0.05). Our results showed that inhibition of TGF-beta signalling reduced the percentage of NK cells and the expression of certain chemokines in the lungs, resulting in improvement of ILD. The findings suggest that TGF-beta signalling may play an important role in the pathogenesis of IL-18 plus IL-2-induced ILD in mice.


Subject(s)
Antineoplastic Agents/adverse effects , Interleukin-18/adverse effects , Interleukin-2/adverse effects , Lung Diseases, Interstitial/immunology , Signal Transduction/immunology , Transforming Growth Factor beta/immunology , Acute Disease , Animals , Antineoplastic Agents/pharmacology , Benzamides/pharmacology , Chemokines/biosynthesis , Chemokines/genetics , Chemokines/immunology , Dioxoles/pharmacology , Humans , Interferon-gamma/biosynthesis , Interferon-gamma/genetics , Interferon-gamma/immunology , Interleukin-18/pharmacology , Interleukin-2/pharmacology , Interleukin-6/biosynthesis , Interleukin-6/genetics , Interleukin-6/immunology , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Killer Cells, Natural/pathology , Lung Diseases, Interstitial/chemically induced , Lung Diseases, Interstitial/genetics , Lung Diseases, Interstitial/metabolism , Lung Diseases, Interstitial/pathology , Mice , Mice, Knockout , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/immunology , Protein Serine-Threonine Kinases/metabolism , RNA, Messenger/genetics , RNA, Messenger/immunology , RNA, Messenger/metabolism , Receptor, Transforming Growth Factor-beta Type I , Receptors, Transforming Growth Factor beta/antagonists & inhibitors , Receptors, Transforming Growth Factor beta/genetics , Receptors, Transforming Growth Factor beta/immunology , Receptors, Transforming Growth Factor beta/metabolism , Signal Transduction/drug effects , Signal Transduction/genetics , Smad3 Protein/genetics , Smad3 Protein/immunology , Smad3 Protein/metabolism , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/metabolism
6.
Clin Exp Immunol ; 159(1): 1-10, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19807734

ABSTRACT

To determine the cytokine balance in patients with lupus nephritis (LN), we analysed kidney-infiltrating T cells. Renal biopsy samples from 15 systemic lupus erythematosus (SLE) patients were used. In accordance with the classification of International Society of Nephrology/Renal Pathology Society, they were categorized into Class III, Class III+V (Class III-predominant group, n = 4), Class IV, Class IV+V (Class IV-predominant group, n = 7) and Class V (n = 4) groups. The single-cell samples of both the glomelular and interstitial infiltrating cells were captured by laser-microdissection. The glomerular and interstitial infiltrating T cells produced interleukin (IL)-2, IL-4, IL-10, IL-13 and IL-17 cytokines in the Class III-predominant, Class IV-predominant and Class V groups. Interferon-gamma was detected only in the glomeruli of the Class III-predominant and Class V group samples. The expression level of IL-17 was correlated closely with clinical parameters such as haematuria, blood urea nitrogen level, SLE Disease Activity Index scores in both glomeruli and interstitium, urine protein level in glomeruli and serum creatinine and creatinine clearance levels in interstitium. This suggests that the glomerular infiltrating T cells might act as T helper type 1 (Th1), Th2 and Th17 cells while the interstitial infiltrating T cells, act as Th2 and Th17 cells in the Class III-predominant and Class V groups. In contrast, both the glomerular and interstitial infiltrating T cells might act as Th2 and Th17 cells in the Class IV-predominant group. The cytokine balances may be dependent upon the classification of renal pathology, and IL-17 might play a critical role in SLE development.


Subject(s)
Cytokines/metabolism , Kidney/metabolism , Laser Therapy , Lupus Nephritis/metabolism , Microdissection/methods , T-Lymphocytes/metabolism , Actins/genetics , Adolescent , Adult , Biomarkers/blood , Biomarkers/urine , Biopsy , Cytokines/genetics , Female , Gene Expression/genetics , Humans , Interferon-gamma/metabolism , Interleukin-17/genetics , Interleukins/metabolism , Kidney/pathology , Kidney/surgery , Kidney Glomerulus/metabolism , Kidney Glomerulus/pathology , Lupus Nephritis/immunology , Lupus Nephritis/pathology , Lupus Nephritis/surgery , Male , Middle Aged , Receptors, Antigen, T-Cell, alpha-beta/genetics , Severity of Illness Index , T-Lymphocyte Subsets/metabolism , T-Lymphocytes/immunology , Th1 Cells/metabolism , Th2 Cells/metabolism , Young Adult
7.
J Neurophysiol ; 100(5): 2486-95, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18753321

ABSTRACT

Macaque monkeys do not reliably discriminate binocular depth cues until about 8 wk of age. The neural factors that limit the development of fine depth perception in primates are not known. In adults, binocular depth perception critically depends on detection of relative binocular disparities and the earliest site in the primate visual brain where a substantial proportion of neurons are capable of discriminating relative disparity is visual area 2 (V2). We examined the disparity sensitivity of V2 neurons during the first 8 wk of life in infant monkeys and compared the responses of V2 neurons to those of V1 neurons. We found that the magnitude of response modulation in V2 and V1 neurons as a function of interocular spatial phase disparity was adult-like as early as 2 wk of age. However, the optimal spatial frequency and binocular response rate of these disparity sensitive neurons were more than an octave lower in 2- and 4-wk-old infants than in adults. Consequently, despite the lower variability of neuronal firing in V2 and V1 neurons of infant monkeys, the ability of these neurons to discriminate fine disparity differences was significantly reduced compared with adults. This reduction in disparity sensitivity of V2 and V1 neurons is likely to limit binocular depth perception during the first several weeks of a monkey's life.


Subject(s)
Animals, Newborn/growth & development , Vision Disparity/physiology , Visual Cortex/physiology , Action Potentials/physiology , Age Factors , Animals , Functional Laterality , Macaca mulatta , Neurons/physiology , Orientation/physiology , Photic Stimulation/methods , Visual Cortex/cytology
8.
J Neurophysiol ; 97(6): 3905-16, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17428899

ABSTRACT

The temporal contrast sensitivity of human infants is reduced compared to that of adults. It is not known which neural structures of our visual brain sets limits on the early maturation of temporal vision. In this study we investigated how individual neurons in the primary visual cortex (V1) and visual area 2 (V2) of infant monkeys respond to temporal modulation of spatially optimized grating stimuli and a range of stimulus contrasts. As early as 2 wk of age, V1 and V2 neurons exhibited band-pass temporal frequency tuning. However, the optimal temporal frequency and temporal resolution of V1 neurons were much lower in 2- and 4-wk-old infants than in 8-wk-old infants or adults. V2 neurons of 8-wk-old monkeys had significantly lower optimal temporal frequencies and resolutions than those of adults. Onset latency was longer in V1 at 2 and 4 wk of age and was slower in V2 even at 8 wk of age than in adults. Contrast threshold of V1 and V2 neurons was substantially higher in 2- and 4-wk-old infants but became adultlike by 8 wk of age. For the first 4 wk of life, responses to high-contrast stimuli saturated more readily in V2. The present results suggest that although the early development of temporal vision and contrast sensitivity may largely depend on the functional maturation of precortical structures, it is also likely to be limited by immaturities that are unique to V1 and V2.


Subject(s)
Contrast Sensitivity/physiology , Neurons, Afferent/physiology , Visual Cortex/cytology , Visual Cortex/growth & development , Action Potentials/physiology , Analysis of Variance , Animals , Animals, Newborn , Macaca mulatta , Photic Stimulation/methods , Reaction Time/physiology
9.
J Neurophysiol ; 97(4): 2612-26, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17267754

ABSTRACT

Visual performance improves with practice (perceptual learning). In this study, we sought to determine whether or not adult monkeys reared with early abnormal visual experience improve their stereoacuity by extensive psychophysical training and testing, and if so, whether alterations of neuronal responses in the primary visual cortex (V1) and/or visual area 2 (V2) are involved in such improvement. Strabismus was optically simulated in five macaque monkeys using a prism-rearing procedure between 4 and 14 wk of age. Around 2 yr of age, three of the prism-reared monkeys ("trained" monkeys) were tested for their spatial contrast sensitivity and stereoacuity. Two other prism-reared monkeys received no training or testing ("untrained" monkeys). Microelectrode experiments were conducted around 4 yr of age. All three prism-reared trained monkeys showed improvement in stereoacuity by a factor of 7 or better. However, final stereothresholds were still approximately 10-20 times worse than those in normal monkeys. In V1, disparity sensitivity was drastically reduced in both the trained and untrained prism-reared monkeys and behavioral training had no obvious effect. In V2, the disparity sensitivity in the trained monkeys was better by a factor of approximately 2.0 compared with that in the untrained monkeys. These data suggest that the observed improvement in stereoacuity of the trained prism-reared monkeys may have resulted from better retention of disparity sensitivity in V2 and/or from "learning" by upstream neurons to more efficiently attend to residual local disparity information in V1 and V2.


Subject(s)
Learning/physiology , Neurons/physiology , Perceptual Distortion/physiology , Vision, Binocular/physiology , Visual Cortex/physiology , Visual Perception/physiology , Animals , Conditioning, Operant/physiology , Cues , Data Interpretation, Statistical , Depth Perception/physiology , Dominance, Ocular/physiology , Electrophysiology , Macaca mulatta , Photic Stimulation , Strabismus/physiopathology , Vision Disparity/physiology , Visual Acuity/physiology
10.
J Neurophysiol ; 95(5): 2856-65, 2006 May.
Article in English | MEDLINE | ID: mdl-16452254

ABSTRACT

Experiencing daily brief periods of unrestricted vision during early monocular form deprivation prevents or reduces the degree of resulting amblyopia. To gain insight into the neural basis for these "protective" effects, we analyzed the monocular and binocular response properties of individual neurons in the primary visual cortex (V1) of macaque monkeys that received intermittent unrestricted vision. Microelectrode-recording experiments revealed significant decreases in the proportion of units that were dominated by the treated eyes, and the magnitude of this ocular dominance imbalance was correlated with the degree of amblyopia. The sensitivity of V1 neurons to interocular spatial phase disparity was significantly reduced in all treated monkeys compared with normal adults. With unrestricted vision, however, there was a small but significant increase in overall disparity sensitivity. Binocular suppression was prevalent in monkeys with constant form deprivation but significantly reduced by the daily periods of unrestricted vision. If neurons exhibited consistent responses to stimulation of the treated eye, monocular response properties obtained by stimulation of the two eyes were similar. These results suggest that the observed protective effects of brief periods of unrestricted vision are closely associated with the ability of V1 neurons to maintain their functional connections from the deprived eye and that interocular suppression in V1 may play an important role in regulating synaptic plasticity of these monkeys.


Subject(s)
Contrast Sensitivity/physiology , Neurons/physiology , Sensory Deprivation/physiology , Vision, Monocular/physiology , Visual Cortex/physiology , Animals , Animals, Newborn , Behavior, Animal , Macaca mulatta , Orientation/physiology , Photic Stimulation/methods , Time Factors , Visual Cortex/cytology , Visual Cortex/growth & development
11.
Mod Rheumatol ; 13(1): 90-4, 2003 Mar.
Article in English | MEDLINE | ID: mdl-24387124

ABSTRACT

Abstract We describe two cases of Behçet's disease associated with myelodysplastic syndrome (MDS) with trisomy 8. Both cases developed ulceration in the cecum as a gastrointestinal complication of Behçet's disease, after a diagnosis of MDS. We summarized recent case reports of Behçet's disease associated with myelodysplastic syndrome, and studied the clinical manifestations. Most cases showed trisomy 8 as a chromosomal abnormality. Gastrointestinal involvement without eye lesions seems to be characteristic of Behçet's disease associated with MDS.

12.
J Mater Sci Mater Med ; 13(4): 397-401, 2002 Apr.
Article in English | MEDLINE | ID: mdl-15348615

ABSTRACT

Pure titanium and some of its alloys are currently considered as the most attractive metallic materials for biomedical applications due to their excellent mechanical properties, corrosion resistance, and biocompatibility. It has been demonstrated that titanium and titanium alloys are well accepted by human tissues as compared to other metals such as SUS316L stainless steel and Co-Cr-Mo type alloy. In the present study, highly porous titanium foams with porosities

13.
Gan To Kagaku Ryoho ; 28(12): 1897-9, 2001 Nov.
Article in Japanese | MEDLINE | ID: mdl-11729483

ABSTRACT

Hepatic infusion of docetaxel using PEIT was performed for a patient with stage IV breast cancer. Docetaxel was effective to a solitary liver metastatic lesion. A 64-year-old woman was admitted to our hospital because of a left breast mass that was bleeding. She was diagnosed with stage IV breast cancer. Surgery was performed on February 16th. The pathological diagnosis was invasive ductal carcinoma, and hormone receptors were negative. Two weeks after operation, monthly docetaxel injections were given together with doxifluidine 400 mg/day p.o., cyclophosphamide 50 mg/day p.o., and fadrozole hydrochloride hydrate 2 mg/day p.o. After two courses, hepatic infusion of docetaxel was performed using PEIT after informed consent. The patient's high serum CEA and CA15-3 level returned to the normal range. A metastatic lesion on CT changed to a cystic pattern. These results suggest that PEIT is worth trying in patients with solitary liver metastasis from breast cancer.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/drug therapy , Carcinoma, Ductal, Breast/secondary , Liver Neoplasms/drug therapy , Liver Neoplasms/secondary , Paclitaxel/analogs & derivatives , Paclitaxel/therapeutic use , Taxoids , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cyclophosphamide/administration & dosage , Docetaxel , Drug Administration Schedule , Ethanol/administration & dosage , Fadrozole/administration & dosage , Female , Floxuridine/administration & dosage , Hepatic Artery , Humans , Infusions, Intra-Arterial , Injections, Intralesional , Middle Aged
15.
Life Sci ; 68(8): 933-42, 2001 Jan 12.
Article in English | MEDLINE | ID: mdl-11213363

ABSTRACT

A study was done to determine how lipid microspheres (LM) containing prostaglandin E1 (lipo PGE1) accumulate in injured arterial tissue. After administration of lipo PGE1 labeled with a fluorescence probe, 1,1'-dioctadecyl-3, 3, 3',3'-tetramethyl-indocarbocyanine perchlorate (DiI-lipo PGE1) to rats 14 of days after balloon injury of the carotid artery, localization into the injured site was examined using a fluorescence confocal laser scanning microscope (CLSM). In contrast with the normal carotid artery, DiI-lipo PGE1 accumulated remarkably in neointima of the injured site which was occupied mainly by the migration of the proliferating and quiescent vascular smooth muscle cells (SMC). In vitro cellular uptake of DiI-lipo PGE1 was semi-quantitatively measured using CLSM, regarding differentiated and proliferative phenotypes of human vascular SMC, compared with the human endothelial cells (EC) and mouse fibroblasts. The differentiated SMC incorporated DiI-lipo PGE1 to equal or a higher level of the proliferative phenotype, and was significantly higher than EC and fibroblasts. The uptake of DiI-lipo PGE1 by both SMC and EC was inhibited at 4 degrees C, by dansylcadaverine and excessive LM, but was unaffected by cytochalasin B. These results suggest that the uptake of DiI-lipo PGE1 by SMC plays an important role in localization of DiI-lipo PGE1 at the injured site, and that the uptake seems to be a receptor mediated endocytosis.


Subject(s)
Alprostadil/pharmacokinetics , Cadaverine/analogs & derivatives , Muscle, Smooth, Vascular/metabolism , Tunica Intima/metabolism , 3T3 Cells/metabolism , Animals , Cadaverine/pharmacology , Carbocyanines/pharmacokinetics , Carotid Artery Injuries/metabolism , Carotid Artery Injuries/pathology , Catheterization/adverse effects , Cytochalasin B/pharmacology , Fluorescent Dyes/pharmacokinetics , Humans , Liposomes , Male , Mice , Microspheres , Rats , Rats, Wistar , Tunica Intima/pathology
16.
Invest Ophthalmol Vis Sci ; 41(12): 4022-31, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11053308

ABSTRACT

PURPOSE: To better understand the course of cortical maturation during early development, the phenomenon of binocular cross-orientation suppression in neurons of the primary visual cortex (V1) in young infant monkeys was investigated. METHODS: Extracellular single-unit recordings were made in anesthetized and paralyzed monkeys ranging in age between 6 days and 8 weeks. Orthogonally oriented, dichoptic sine-wave gratings were used as visual stimuli. RESULTS: V1 neurons in young infant monkeys showed a higher prevalence and greater magnitude of binocular cross-orientation suppression than in adult monkeys. Binocular suppression decreased and reached an adult level between 4 and 8 weeks of age, the presumed onset-age for stereopsis in monkeys. CONCLUSIONS: During the first 4 weeks of life, the functional connections that are necessary for initiating binocular cross-orientation suppression exist in the monkey primary visual cortex. This finding is consistent with the view that before the abrupt onset of stereopsis, human infants may detect the differences between interocularly iso-oriented gratings and orthogonal gratings.


Subject(s)
Macaca mulatta/physiology , Orientation/physiology , Vision, Binocular/physiology , Visual Cortex/physiology , Aging/physiology , Animals , Animals, Newborn , Depth Perception/physiology , Neurons/physiology
17.
Invest Ophthalmol Vis Sci ; 41(3): 948-54, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10711717

ABSTRACT

PURPOSE: By 6 weeks of age, neurons in the monkey's primary visual cortex acquire qualitatively adult-like binocular response properties and behaviorally stereopsis emerges. In this study, it was determined whether the onset of strabismus has a more severe impact on cortical binocularity before or after this critical developmental age. METHODS: Infant monkeys were fit with a light-weight helmet which held a total of 27 diopters of base-in prisms in front of their two eyes for a fixed period of two weeks. For one group of infant monkeys, prism-rearing began at 2 weeks of age and for a second group, the onset was at 6 weeks of age. Immediately after the rearing period, i.e., at 4 weeks and 8 weeks of age, respectively, extracellular single-unit recording methods were used to determine the nature and severity of alterations in the binocular response properties of V1 neurons. Dichoptic sinewave gratings were used as visual stimuli. RESULTS: In comparison to normal age-matched infants, V1 neurons in both strabismic groups exhibited reductions in sensitivity to interocular spatial phase disparities (disparity sensitivity) and a higher prevalence of binocular inhibitory interactions (binocular suppression). However, the reduction in disparity sensitivity and the magnitude of binocular suppression were much greater in the late (6-8 weeks) than the early (2- 4 weeks) onset group. CONCLUSIONS: Discordant binocular signals due to brief periods of early strabismus have more serious effects on the development of binocular properties of V1 neurons if they occur shortly after rather than before the emergence of stereopsis (i.e., when the binocular connections are relatively more mature but the visual cortex still shows a high degree of plasticity).


Subject(s)
Neurons/physiology , Strabismus/physiopathology , Vision, Binocular/physiology , Visual Cortex/physiopathology , Age of Onset , Animals , Depth Perception/physiology , Macaca mulatta , Vision Disparity/physiology
18.
Jpn J Pharmacol ; 81(1): 107-14, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10580378

ABSTRACT

Prostaglandin E1 incorporated in lipid microspheres (lipo PGE1) was administered to the umbilical vein of neonatal rats. Morphological measurement and quantitative autoradioluminography assessed the relationship between the vasodilating effect and tissue accumulation of lipo PGE1 in the ductus arteriosus. In the morphological measurement under microscopy, the inner diameter ratio of the ductus arteriosus to the main pulmonary artery after infusion of 3H-labeled lipo PGE1 (3H-lipo PGE1) continued to remain significantly higher than that of free 3H-PGE1. Autoradioluminography of the frozen frontal section of neonates after intravenous infusion of 3H-lipo PGE1 for 2 h revealed that the ductus levels of radioactivity were higher than those of free 3H-PGE1 in saline solution, although the blood levels were almost equal. Localization of lipo PGE1 labeled with a lipophilic fluorescent probe, 1,1'-dioctadecyl-3,3,3',3-tetramethyl-indocarbocyanine perchlorate (diI), in the endothelial cells of the ductus arteriosus was confirmed by confocal laser scanning microscopy. These findings suggest that the incorporation of lipid microspheres by the endothelial cells is one of the mechanisms that enables lipo PGE1 to accumulate to higher levels in the ductus tissue and to act more efficiently than free PGE1 in neonatal rats.


Subject(s)
Alprostadil/administration & dosage , Alprostadil/pharmacokinetics , Ductus Arteriosus/drug effects , Ductus Arteriosus/metabolism , Vasodilator Agents/administration & dosage , Vasodilator Agents/pharmacokinetics , Alprostadil/blood , Animals , Dose-Response Relationship, Drug , Drug Carriers , Ductus Arteriosus/ultrastructure , Female , Infusions, Intravenous , Liposomes , Microscopy, Confocal , Microscopy, Fluorescence , Microspheres , Pregnancy , Rats , Tissue Distribution , Tritium , Umbilical Veins , Vasodilator Agents/blood
19.
Restor Neurol Neurosci ; 15(2-3): 165-76, 1999.
Article in English | MEDLINE | ID: mdl-12671231

ABSTRACT

The mature visual cortex is capable of reorganizing its functional connections in response to retinal injuries. Although this phenomenon is well established, there are a number of unresolved issues. This paper will review some of the more critical aspects of adult plasticity including those based on our most recent findings. Our preliminary data indicate that a large-scale reorganization of cortical maps following retinal injuries may require an increase in synaptic strengths at key cortical sites promoted by long-term, repeated use.

20.
Invest Ophthalmol Vis Sci ; 39(12): 2259-67, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9804134

ABSTRACT

PURPOSE: Optokinetic nystagmus (OKN) in young infants typically shows a temporal-to-nasal asymmetry under monocular viewing conditions. The neural basis for this asymmetry has been a matter of debate. One idea is that the OKN asymmetry reflects a similar asymmetry in the directional sensitivity of primary visual cortical (V1) neurons. An alternative hypothesis is that the OKN asymmetry is due to an immaturity in the ability of cortical neurons to influence the activity of subcortical structures that directly control OKN. We addressed this issue by studying the directional sensitivity of V1 neurons in young infant monkeys. METHODS: The neuronal activity of V1 units was recorded from anesthetized and paralyzed rhesus monkeys ranging in age from 6 days to 8 weeks using standard extracellular single-unit recording methods. For comparison, V1 units from normal adult monkeys were also studied. Using drifting sinusoidal gratings of the optimal spatial frequency and a moderate contrast, we measured the responsiveness of individual units to 24 directions of stimulus movement. The preferred stimulus direction and the magnitude of the directional response bias were determined by a vector summation method. RESULTS: No clear signs of nasotemporal asymmetries in direction tuning were found in our cell population from infant monkeys. However, the overall directional sensitivity and the peak monocular response amplitudes of these units were significantly lower, and binocular suppression was greater during the first 4 weeks of life than in adults. CONCLUSIONS: The OKN asymmetry in young infants may be more closely associated with the lower overall directional sensitivity and the subnormal responsiveness of V1 neurons rather than with an obvious asymmetry in the directional properties of V1 neurons.


Subject(s)
Macaca mulatta/physiology , Neurons/physiology , Nystagmus, Optokinetic/physiology , Visual Cortex/physiology , Action Potentials/physiology , Aging/physiology , Animals , Animals, Newborn/physiology , Motion Perception/physiology , Vision, Binocular/physiology
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