24 results on '"Kuo HR"'
Search Results
2. Localization of Z-RNA in Normal Lens Epithelium: Middle Fibers
- Author
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Gagna, CE, Kuo, HR, Schulz, R, Cordova, R, Crippen, G, and Lambert, WC
- Abstract
The goal of this project was to analyze the cellular localization of Z-RNA, within middle fibers (MF) of the adult dog ocular lens (1.5 yr) (Fig. 1), using anti-Z-RNA IgG polyclonal antibodies. B-DNA can adopt the left-handed Z-DNA conformation in vitro(1). Right-handed A-RNA can be transformed into left-handed Z-RNA (2). Z-RNA has been studied in cultured cells (3). Evidence supports the presence of Z-DNA in vivo(1). Removal of DNA binding proteins by fixatives can initiate supercoiling which stabilizes Z-DNA sequences (1).Anti-Z-RNA polyclonal antibody probes were developed in rabbits immunized with multiple injections of Z-RNA: Br-poly[ribosomal(G-C)]. Regarding immunohistochemistry, lens tissues were fixed in Carnoy's, embedded in paraffin and sectioned (2.5 μm) (Fig. 2). Computerized image analysis was performed using a Leitz DM-RB microscope and Leica Quantiment 500 + image analyzer.
- Published
- 2000
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3. Left-Handed Z-Rna In Lens Epithelium: Preequatorial Zone
- Author
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Gagna, CE, Kuo, HR, and Lambert, WC
- Abstract
Our goal was to determine the cellular localization of left-handed Z-RNA, within preeguatorial zone (PZ) epithelium of the normal adult dog ocular lens (1.5 yr) (Fig. 1), employing anti-Z-RNA IgG polyclonal antibodies. B-DNA has the ability to adopt the Z-DNA configuration in vitro(1). A-RNA can be transformed into Z-RNA under certain conditions (2). Z-RNA has been localized in cultured cells (3). Strong evidence supports the presence of Z-DNA in vivo(1). Elimination of DNA binding proteins by certain fixatives can initiate DNA supercoiling which stabilizes Z-DNA sequences (1). Z-DNA may play a role in regulating in vivotranscriptional enhancement (1).Anti-Z-RNA antibody probes were produced in 3 rabbits immunized with injections of Z-RNA: Br-poly[ribosomal(G-C)]. Concerning light microscopy [immunohistochemistry (ABC method)], lens tissues were fixed in Carnoy's, embedded in paraffin and sectioned (3 μm) (Fig. 2). Image analysis was performed using a Leitz DM-RB microscope and Leica Quantiment 500 + image analyzer.
- Published
- 1999
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4. Demonstration of Z-RNA in the Dog Eye Lens Epithelium (Germinative Zone)
- Author
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Gagna, CE, Chen, JH, Kuo, HR, and Lambert, WC
- Abstract
The purpose of this scientific investigation was to determine the presence and specific cellular localization of left-handed Z-RNA, within germinative zone (GZ) epithelium of the lens (Fig. 1), using anti-Z-RNA IgG polyclonal antibodies. Right-handed B-DNA has the ability to adopt the Z-DNA conformation in vitro(Sinden, 1994). Right-handed A-RNA can be transformed into Z-RNA under specific conditions (Hall et al., 1984), and Z-RNA has been identified in cultured cells (Zarling et al., 1990). Strong evidence supports the idea of Z-DNA in vivo(Sinden, 1994). Removal of proteins by fixatives can induce supercoiling which stabilizes Z-DNA (Sinden, 1994).Anti-Z-RNA antibodies were produced in rabbits immunized with injections of Z-RNA: brominated-poly[ribosomal(G-C)]. For light microscopy, immunohistochemical studies (ABC method), normal dog lens tissues (1 yr old) were fixed in Carnoy's, embedded in paraffin and sectioned 2 μm thick. For electron microscopy (immunogold staining), pieces of epithelium from the GZ of normal dog lens (1 yr old) were fixed with 5% glutaraldehyde in 0.05 M phosphate buffer solution, pH 7.3.
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- 1998
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5. Natural Compounds Targeting Cancer-Associated Fibroblasts against Digestive System Tumor Progression: Therapeutic Insights.
- Author
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Chiu KJ, Chiou HC, Huang CH, Lu PC, Kuo HR, Wang JW, and Lin MH
- Abstract
Cancer-associated fibroblasts (CAFs) are critical for cancer occurrence and progression in the tumor microenvironment (TME), due to their versatile roles in extracellular matrix remodeling, tumor-stroma crosstalk, immunomodulation, and angiogenesis. CAFs are the most abundant stromal component in the TME and undergo epigenetic modification and abnormal signaling cascade activation, such as transforming growth factor-β (TGF-β) and Wnt pathways that maintain the distinct phenotype of CAFs, which differs from normal fibroblasts. CAFs have been considered therapeutic targets due to their putative oncogenic functions. Current digestive system cancer treatment strategies often result in lower survival outcomes and fail to prevent cancer progression; therefore, comprehensive characterization of the tumor-promoting and -restraining CAF activities might facilitate the design of new therapeutic approaches. In this review, we summarize the enormous literature on natural compounds that mediate the crosstalk of CAFs with digestive system cancer cells, discuss how the biology and the multifaceted functions of CAFs contribute to cancer progression, and finally, pave the way for CAF-related antitumor therapies.
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- 2022
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6. Hyperbaric Oxygen Therapy Alleviates the Autoimmune Encephalomyelitis via the Reduction of IL-17a and GM-Csf Production of Autoreactive T Cells as Well as Boosting the Immunosuppressive IL-10 in the Central Nervous System Tissue Lesions.
- Author
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Chiou HC, Huang SH, Hung CH, Tsai SM, Kuo HR, Huang YR, Wang JW, Chen SC, Kuo CH, Wu DC, Huang SK, Hsu SH, and Lin MH
- Abstract
Multiple sclerosis (MS) is a chronic autoimmune disease mainly caused by autoreactive T cells, followed by neuronal demyelination and disabling paralysis. Hyperbaric oxygen therapy (HBOT) is usually an adjunct to therapy for the treatment of neurological disorders. However, it remains still controversial whether HBOT is an effective option for the treatment of MS. Experimental autoimmune encephalomyelitis (EAE) is a well-studied mouse model investigated for the MS pathogenesis and the efficacy of the therapeutic intervention. Both encephalitogenic Th1 and Th17 are pivotal T cell subsets immunopathogenically producing several disease-initiating/modifying cytokines in the central nervous system (CNS) lesions to further exacerbate/ameliorate the progression of EAE or MS. However, it remains unclear whether HBOT modulates the context of T helper cell subsets in CNS lesions. We employed EAE in the presence of HBOT to assess whether disease amelioration is attributed to alterations of CNS-infiltrating T cell subsets. Our results demonstrated that semi-therapeutic HBOT significantly alleviated the progression of EAE, at least, via the suppression of Th17 response, the downregulation of CD4 T helper cells expressing GM-CSF or TNF-α, and the boosting of immunomodulatory IL-4 or IL-10-expressed CD4 T cells in the CNS lesions. Conclusively, HBOT attenuated EAE through the modulation of T cell responses in an earlier stage.
- Published
- 2021
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7. A comparative proteomic study of secretomes in kaempferitrin-treated CTX TNA2 astrocytic cells.
- Author
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Ku WC, Chang YL, Wu SF, Shih HN, Tzeng YM, Kuo HR, Chang KM, Agrawal DC, Liu BL, Chang CA, Huang S, and Lee MJ
- Subjects
- Animals, Astrocytes metabolism, Cell Line, Cinnamomum chemistry, Cytokines metabolism, Hypoglycemic Agents pharmacology, Plant Extracts chemistry, Plant Extracts pharmacology, Plant Leaves chemistry, Proteomics methods, Rats, Tandem Mass Spectrometry, Astrocytes drug effects, Kaempferols pharmacology, Proteins metabolism
- Abstract
Ethnopharmacological Relevance: Kaempferitrin is extracted in significantly high quantities from the leaves of Cinnamomum osmophloeum (C.O) and Bauhinia forficata, and are used as an antidiabetic herbal remedy in China and Brazil. Commercial product using dry Cinnamomum osmophloeum leaves has been sold locally in Taiwan. Oral administration of kaempferitrin reduced blood sugar in diabetic rats., Aim of the Study: Though previously demonstrated to activate the classical insulin signaling pathways, a mechanism for kaempferitrin is still not fully understood. Also, studies on kaempferitrin on immune related cells have been inconclusive, and people consuming extract containing kaempferitrin often happen to be at high risk of diabetes and neurodegenerative diseases. Therefore, for kaempferitrin to be used every day, a comprehensive study is needed., Materials and Methods: Astrocytic cell line was used as a model to test the differentially regulated secretomes, to test kaempferitrin effect on CNS glia, on pro-inflammatory cytokines, and to test how different the mechanism of kaempferitrin is from that of insulin. CTX TNA2 astrocytic cells were differentially treated with and without 10 µM kaempferitrin for 24 h, and the conditioned medium was collected. For the proteomic study, protein in conditioned medium was trypsin digested, and resulting peptides in kaempferitrin/non-treated sample pair were differentially dimethyl labeled. The labeled peptides were further fractionated by StageTip-based strong-exchange method before LC-MS/MS analyses. Levels of interesting proteins were verified using Western or Eliza. C.O. leaf crude extract treated samples were included for a comparison of effects of purified kaempferitrin vs. kaempferitrin containing crude extract., Results and Conclusions: Data were obtained via ProteomeXchange with identifier PXD002814. It was found that no pro-inflammatory cytokines or inhibitory ECM were elevated upon treatment of kaempferitrin or a crude extract of C.O. leaves. This suggests that prolonged use of kaempferitrin containing herbs may not increase pro-inflammatory reaction. LDL-R trafficking between the cell membrane and the extracellular niche was regulated by kaempferitrin toward reduced secretion. Our proteomic study also demonstrated that molecules related to plasma membrane recycling were regulated by kaempferitrin. Our discoveries provide evidence that link kaempferitrin regulation for LDL-R and membrane recycling to the blood lipid regulation by the C.O. leaves extract. However, these proteins were differently regulated when cells were treated with crude extract. This demonstrates that the molecular interactions within crude extract of herbs are complex and may not act similar to the compound purified from the crude extract., (Copyright © 2017 Elsevier GmbH. All rights reserved.)
- Published
- 2017
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8. Low temperature and high magnetic field spectroscopic ellipsometry system.
- Author
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Su SK, Li LC, Suen YW, Wu JY, Kuo HR, Sung YT, Lee CP, and Voskoboynikov O
- Abstract
We report on the design and implementation of a spectral ellipsometer at near-infrared wavelength (700-1000 nm) for samples placed in high magnetic fields (up to 14 T) at low temperatures (~4.2 K). The main optical components are integrated in a probe, which can be inserted into a conventional long-neck He dewar and has a very long free-space optical path (~1.8 m×2). A polarizer-sample-(quarter-wave plate)-rotating analyzer configuration was employed. Two dielectric mirrors, one before and one after the sample in the optical path, helped to reflect the light back to the analyzer and a two-axis piezo-driven goniometer under the sample holder was used to control the direction of the reflected light. Functional test results performed on an intrinsic GaAs wafer and analysis on the random error of the system are shown. We obtained both amplitude and phase ellipsometric spectra simultaneously and observed helicity transformation at energies near the GaAs exciton transitions in the phase spectra. Significant shifts of them induced by magnetic fields were observed and fitted with a simple model. This system will allow us to study the collective magneto-optical response of materials and spatial dispersive exciton-polariton related problems in high external magnetic fields at low temperatures.
- Published
- 2014
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9. Localization and quantification of intact, undamaged right-handed double-stranded B-DNA, and denatured single-stranded DNA in normal human epidermis and its effects on apoptosis and terminal differentiation (denucleation).
- Author
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Gagna CE, Chan NJ, Farnsworth PN, Kuo HR, Kanthala TR, Patel AH, Patel NH, Law A, Patel PP, Richards SA, Yam T, Nici A, and Lambert WC
- Subjects
- Adult, Cell Differentiation, Cell Nucleus metabolism, DNA, Single-Stranded analysis, Epidermal Cells, Epidermis chemistry, Humans, Keratinocytes cytology, Keratinocytes physiology, Nucleic Acid Denaturation, Apoptosis, DNA, Single-Stranded metabolism, Epidermis physiology
- Abstract
Quantification of two types of nucleic acids [double-stranded (ds-) and single-stranded (ss-) DNA] was performed to understand the distribution of DNA within the epidermal strata and to examine the effects of DNA structure on gene expression, viz., apoptosis and terminal differentiation. In addition, we examined the precise starting point of cell death within the epidermis (suprabasal layer); examined how DNA structure affects gene expression of melanocytes; and characterized the "transitional cells" located between the stratum granulosum and stratum corneum, viz., epidermal phase transition zone (EPTZ). Ultrasensitive anti-DNA antibody probes (ds-DNA, ss-DNA), the Feulgen reaction, histological stains (morphological characterization) and the terminal deoxyribonucleotidyl transferase (TUNEL) assay (apoptosis) were used to characterize cell death in normal human epidermis. This study characterized, for the first time, the deterioration of right-handed ds-B-DNA and the increase in denatured ss-DNA during epidermal maturation. For the first time, this approach also allowed for the quantitative and qualitative characterization of DNA content and structure in all epidermal strata, using anti-ds-B-DNA and anti-ss-DNA antibodies. In order to improve the retention and quality of DNA, a novel histotechnological processing procedure was used. The results indicate that the largest decline in DNA occurred within the stratum granulosum, followed by the EPTZ, and the stratum spinosum. Not all epidermal nuclei lost DNA, indicating two differentiating keratinocyte pathways, viz., apoptotic and non-apoptotic. Both pathways united in the stratum granulosum. These results suggest that keratinocyte terminal differentiation and apoptosis are distinct cellular events, cell death begins earlier than expected, and molecular epidermal events take place in a gradual and orderly manner within keratinocytes. During maturation, ds-B-DNA decreases as ss-DNA increases. Therefore, during differentiation of keratinocytes, both DNA content and DNA structure are altered.
- Published
- 2009
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10. Novel DNA staining method and processing technique for the quantification of undamaged double-stranded DNA in epidermal tissue sections by PicoGreen probe staining and microspectrophotometry.
- Author
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Gagna CE, Kuo HR, Chan NJ, Mitacek EJ, Spivak A, Pasquariello TD, Balgobin C, Mukhi R, and Lambert WC
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- Animals, Fixatives, Fluorescent Dyes, Immunohistochemistry methods, Nucleic Acid Conformation, Nucleic Acid Denaturation, Organic Chemicals, Paraffin Embedding, Ploidies, Sensitivity and Specificity, Staining and Labeling methods, Swine, DNA analysis, Epidermis chemistry, Histocytological Preparation Techniques methods
- Abstract
Histotechnological processing of DNA can cause damage to and loss of DNA and can change its structure. DNA probes have severe tissue-staining limitations. New DNA probes and improved histotechnology are needed to enhance the characterization of fixed tissue-bound DNA. Our team developed a novel DNA staining technique and histotechnological processing procedure that improves tissue-bound DNA retention and the qualification and quantification of intact double-stranded (ds)-B-DNA. We used the ultrasensitive PicoGreen ds-DNA probe for the histochemical characterization of ds-DNA. Fifteen fixatives were examined to determine which were best for preventing DNA denaturation and retaining original DNA content and structures. Our use of a microwave-vacuum oven reduced heating temperatures, shortened heating and processing times, and enhanced fixation. We achieved better qualitative and quantitative results by using superior tissue-acquisition techniques (e.g., reduced prefixation times) and improved histotechnology. We also compared our novel approach with archival tissues, delayed fixation, less sophisticated and conventional histological processing techniques, and by experimenting with preservation of tissue-bound ds-Z-DNA. Results demonstrate that our histotechnological procedure and nucleic acid staining method significantly improve the retention of intact, undamaged ds-DNA which, in turn, allows the investigator to more precisely quantify the content and structures of unaltered and undamaged tissue-bound ds-B-DNA.
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- 2007
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11. Novel use of bovine zeta-crystallin as a conformational DNA probe to characterize a phase transition zone and terminally differentiating fiber cells in the adult canine ocular lens.
- Author
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Gagna CE, Kuo HR, Agostino N, Rizzo D, Isquith IR, Mathew J, Mohammed J, Hoo S, and Lambert WC
- Subjects
- Age Factors, Animals, Antibodies, Monoclonal, Cattle, Cell Differentiation, DNA analysis, DNA immunology, DNA metabolism, DNA, Single-Stranded analysis, DNA, Single-Stranded immunology, DNA, Single-Stranded metabolism, Dogs, Eosine I Bluish, Female, Fluoresceins, Fluorescent Dyes, Image Processing, Computer-Assisted, Male, Nucleic Acid Conformation, Crystallins pharmacokinetics, Immunohistochemistry methods, Lens, Crystalline cytology, Molecular Probe Techniques
- Abstract
Using a novel immunocytochemical staining method, we aimed to characterize the phase transition zone (PTZ) (approximatly 100 microm) in adult ocular lenses and the process of terminal differentiation (denucleation) within normal fiber cells. The binding to DNA of zeta-(zeta) crystallin (Z-DNA-binding protein) and anti-double-stranded (ds-)-B-DNA antibody probes was found to decline gradually throughout denucleating fibers, with a precipitous decrease occurring at about 100 microm (PTZ). Nuclei of superficial fiber cells (in front of the PTZ) showed the highest DNA probe-binding values, followed by middle fibers (MF) and deep fibers (DF). With the use of zeta-crystallin, anti-ds-B-DNA antibody, and anti-single stranded (ss-) DNA antibody probes, it was possible to reveal a loss of reactivity of fiber cell ds-DNA. Ss-DNA antibody binding was seen initially in the MF and reached its highest intensity level in the DF. The pattern of zeta-crystallin probe-DNA reactivity correlates with the loss of anti-B-DNA antibody staining and decreased eosin-protein staining. These data suggest that a reorganization of DNA and intracellular protein supramolecular order in normal adult lenses occurs at a depth of about 100 microm (PTZ).
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- 2001
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12. Comparison of apoptosis and terminal differentiation: the mammalian aging process.
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Gagna CE, Kuo HR, Florea E, Shami W, Taormina R, Vaswani N, Gupta M, Vijh R, and Lambert WC
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- Animals, Cornea chemistry, Cornea cytology, DNA, Single-Stranded analysis, Electrophoresis, Agar Gel, Fixatives, Guinea Pigs, Immunohistochemistry, Lens, Crystalline chemistry, Lens, Crystalline cytology, Nucleic Acid Denaturation, Paraffin Embedding, Skin chemistry, Skin cytology, Aging physiology, Apoptosis
- Abstract
Apoptosis is the ordered chain of events that lead to cell destruction. Terminal differentiation (denucleation) is the process in which cells lose their nuclei but remain functional. Our group examined cell death in three tissues using two different fixatives and a postfixation procedure, involving young (5 months) and old (2 years) guinea pigs. The data reveal that B-DNA and Z-DNA content decreases, whereas single-stranded (ss-) DNA increases, in older tissues undergoing apoptosis (skin and cornea) and terminal differentiation (ocular lens). We speculate that some of the factors that contribute to the aging process might also be responsible for the enhanced amount of damaged DNA in older tissues undergoing cell death. (J Histochem 49:929-930, 2001)
- Published
- 2001
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13. Damage-resistant DNA synthesis in Fanconi anemia cells treated with a DNA cross-linking agent.
- Author
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Centurion SA, Kuo HR, and Lambert WC
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- Cell Line, Cross-Linking Reagents pharmacology, DNA biosynthesis, Fanconi Anemia Complementation Group Proteins, Humans, Methoxsalen pharmacology, Photosensitizing Agents pharmacology, Proteins genetics, S Phase, Cell Cycle Proteins, DNA Adducts drug effects, DNA Damage drug effects, DNA Damage radiation effects, DNA Replication drug effects, DNA-Binding Proteins, Fanconi Anemia genetics, Nuclear Proteins
- Abstract
Fanconi anemia (FA) is a recessive disorder associated with diverse congenital anomalies, progressive bone marrow failure, and a marked predisposition to develop cancer. At the cellular level, FA is characterized by a prolonged G(2) phase in proliferating cells and a marked hypersensitivity to both the cytotoxic and the clastogenic effects of agents which produce DNA interstrand cross-links. Treatment with these agents leads to even further prolongation of the G(2) phase in FA cells. We now show that FA cells, from four different complementation groups, fail to decrease their rates of replicative DNA synthesis, as do normal cells, following treatment with a DNA cross-linking agent. This may be responsible for the prolongation of the G2 phase seen in these cells, and suggests that the fundamental defect in response of FA cells to DNA cross-linking agents may be in the S phase, rather than the G(2) phase, of the cell cycle., (Copyright 2000 Academic Press.)
- Published
- 2000
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14. Effect of antihypertensive therapy on renal injury in type 2 diabetic rats with hypertension.
- Author
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Reddi AS, Nimmagadda VR, Lefkowitz A, Kuo HR, and Bollineni JS
- Subjects
- Albuminuria drug therapy, Animals, Blood Glucose drug effects, Blood Pressure drug effects, Diabetic Nephropathies pathology, Doxazosin therapeutic use, Drug Therapy, Combination, Female, Hypertension physiopathology, Kidney Glomerulus drug effects, Kidney Glomerulus pathology, Lisinopril therapeutic use, Male, Rats, Rats, Inbred SHR, Systole, Antihypertensive Agents therapeutic use, Diabetes Mellitus, Type 2 drug therapy, Diabetic Nephropathies drug therapy, Hypertension drug therapy
- Abstract
In a previous study, we demonstrated that doxazosin (DZN), an alpha(1)-adrenergic blocker, prevented proteinuria in streptozotocin diabetic rats. In this study, we investigated whether DZN would lower established proteinuria by improving glomerular sclerosis in spontaneously hypertensive corpulent rats with type 2 diabetes mellitus. DZN treatment was compared with treatment with angiotensin-converting enzyme inhibitor, lisinopril (LIS) alone, and DZN in combination with LIS. Combination therapy was used to examine any additive effect of either drug alone in the reduction of proteinuria and glomerular sclerosis. Both male and female rats age 6 months with established proteinuria were used. The rats were allocated randomly to 1 of 4 groups: untreated, DZN treated, LIS treated, or a combination of DZN and LIS treatment. Drug treatment was continued for 16 weeks. The results show that (1) either drug alone or in combination significantly lowered systolic blood pressure; (2) DZN, LIS, or combination therapy reduced albuminuria at 16 weeks of treatment from baseline by 38.61+/-5.77%, 30.70+/-4. 21%, and 42.17+/-4.77% (mean+/-SE), respectively. No difference in albuminuria was observed among the 3 groups of rats; (3) the fractional mesangial area, which was 20.55+/-3.77% in untreated rats, was significantly reduced to 11.18+/-1.32% in DZN-treated rats, with a further reduction to 8.72+/-0.64% in LIS-treated rats and to 3.48+/-0.35% in rats treated with DZN+LIS; and (4) DZN but not LIS significantly improved plasma glucose levels in spontaneously hypertensive corpulent rats (untreated 21.06+/-0.97 mmol/L versus DZN treated 15.81+/-0.93 mmol/L or DZN+LIS treated 17.38+/-1.10 mmol/L; P<0.025 to 0.005). Thus, the data suggest that 16-week treatment with either DZN or LIS improves established proteinuria and glomerular sclerosis, but combination therapy is superior to either DZN or LIS alone in preventing glomerular sclerosis in type 2 diabetic rats with hypertension.
- Published
- 2000
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15. Introduction of macromolecules into synaptosomes using electroporation.
- Author
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Ramanathan M, Kuo HR, Lambert CW, and Ingoglia NA
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- Adenosine Triphosphate pharmacology, Animals, Arginine pharmacokinetics, Biological Transport drug effects, Buffers, Cell Membrane metabolism, Cell Survival, Dextrans chemistry, Electric Conductivity, Fluorescein-5-isothiocyanate chemistry, Fluorescein-5-isothiocyanate pharmacokinetics, Male, Molecular Weight, Rats, Rats, Sprague-Dawley, Tritium, Dextrans pharmacokinetics, Electroporation methods, Fluorescein-5-isothiocyanate analogs & derivatives, Synaptosomes metabolism
- Abstract
Synaptic terminals are sites of high metabolic activity and thus are particularly vulnerable to oxidative stress. Oxidative damage to proteins can be toxic to neurons and may cause irreversible cell damage and neurodegeneration. A neuroprotective mechanism used by cells to combat oxidative damage is to selectively degrade damaged proteins. Therefore, it is of interest to study the mechanism of degradation of oxidatively damaged proteins in synaptosomes. One way of oxidizing synaptosomal proteins in vitro is by incubating intact synaptosomes in the presence of an oxidizing agent. A problem with this approach is that it may also cause oxidative damage to the machinery required to recognize and degrade oxidized proteins. We have, therefore, introduced a fluorescent macromolecule into synaptosomes to assess the feasibility of using this technique to study how oxidized proteins are degraded and removed from synaptic terminals. Synaptosomes were subjected to electroporation in the presence of FITC labelled-dextran with an average molecular weight of 70000 (FD-70) and non-specific binding was determined by running parallel experiments in lysed synaptosomes. Following extensive washing, synaptosomes were assayed for the presence of intra-synaptosomal FD-70 by measuring fluorescence in a microplate fluorescence reader. Significant differences in fluorescence were found between intact and lysed synaptosomes with maximal uptake at 100 V/ 1500 microF (approx. 36 pmol/mg protein). To determine if membrane transport was compromised by electroporation, uptake of 3H-arginine was compared in control and electroporated synaptosomes. While untreated electroporated synaptosomes showed a loss of 22% in the ability to transport arginine, preincubation in the presence of 1 mM ATP resulted in a complete restoration of arginine transport. These results show that electroporation is a potentially useful technique for introducing a specific oxidized protein, into synaptic terminals so its metabolic fate can be examined.
- Published
- 2000
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16. Use of anti-single-stranded DNA antibodies to localize and quantify denatured DNA during cell death.
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Gagna CE, Kuo HR, Hornan C, Hammond I, and Lambert WC
- Subjects
- Animals, Antibodies, Antinuclear immunology, DNA, Single-Stranded immunology, Nucleic Acid Denaturation, DNA, Single-Stranded analysis
- Published
- 2000
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17. Terminal differentiation and left-handed Z-DNA: a review.
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Gagna CE, Kuo Hr, and Lambert WC
- Subjects
- Animals, Cell Death, Cell Differentiation, Humans, Nucleic Acid Denaturation, DNA, Gene Expression Regulation
- Abstract
Nucleic acids control the expression of genes, and different conformations of DNA structure may regulate cell death. Left-handed Z-DNA, which is speculated to function as a transcriptional enhancer, may be directly influenced by the destructive effects of terminal differentiation. The nicking-denaturation of double-stranded Z-DNA could possibly initiate and enhance terminal differentiation within specific tissues.
- Published
- 1999
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18. Identification of early apoptosis in feulgen-stained cultured cells in situ by computerized image analysis.
- Author
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Kuo HR, Lapidus A, and Lambert WC
- Subjects
- Coloring Agents, Humans, Staining and Labeling, Tumor Cells, Cultured, Apoptosis, Image Processing, Computer-Assisted methods, Rosaniline Dyes
- Abstract
A method is presented in which Feulgen-stained apoptotic cells are identified among cultured cells in situ using computerized image analysis of their nuclei. Images of either control (untreated) human lymphoblastoid cell nuclei or of similar cells treated with 3mM methyl methanesulfonate for 1 h, which induces apoptosis in 100% of the cells, were converted to a standard size (80 x 80 pixels) and Fourier transforms and boundary images based on 21 proportional mean gray-level thresholds obtained. The perimeter and the mean fractal dimension of the latter and 39 selected coefficients of the former were then obtained from which data were chosen heuristically and subjected to multivariate linear discrimination analysis. Eighty-two percent of a teaching set of 50 nuclei and 69% of a test set of 29 nuclei were correctly identified as apoptotic versus nonapoptotic by the computer, compared with 57% identified correctly by a panel of 7 pathologists. This study shows the feasibility of using this type of analysis to directly identify apoptotic cells in culture, and probably also in tissues, by direct observation using computerized imaging technology.
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- 1998
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19. Localization of left-handed Z-RNA in the outer cortical secondary fiber cells of the adult dog crystalline lens.
- Author
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Gagna CE, Chen JH, Kuo HR, and Lambert WC
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- Animals, Antibodies, Dogs, Immunochemistry, Lens Cortex, Crystalline cytology, Lens Cortex, Crystalline ultrastructure, Microscopy, Electron methods, RNA immunology, Rabbits, Lens, Crystalline cytology, Lens, Crystalline ultrastructure, RNA analysis
- Published
- 1998
20. Binding properties of bovine ocular lens zeta-crystallin to right-handed B-DNA, left-handed Z-DNA, and single-stranded DNA.
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Gagna CE, Chen JH, Kuo HR, and Lambert WC
- Subjects
- Animals, Cattle, Crystallins metabolism, DNA metabolism, DNA, Single-Stranded metabolism, Enzyme-Linked Immunosorbent Assay, Kinetics, Lens, Crystalline anatomy & histology, Protein Binding, Crystallins chemistry, DNA chemistry, DNA, Single-Stranded chemistry, Lens, Crystalline physiology, Nucleic Acid Conformation
- Abstract
Bovine zeta-crystallin has the ability to bind with different DNAs. Initially, this protein was named regulatory factor 36 (Kang et al., 1985), but it has been shown to be an ocular lens zeta-crystallin (Jörnvall et al., 1993), which is considered an enzyme-crystallin (Rodakanaki et al., 1989). The enzyme-linked immunosorbent assay (ELISA) was used to quantitate the binding of bovine zeta-crystallin to purified high molecular weight double-stranded (ds-) and single-stranded (ss-) DNA (bovine and synthetic DNA). ELISA quantitation was achieved by the addition of anti-zeta-crystallin antibodies to the DNA-zeta-crystallin complex, using a novel immunochemical avidin-biotin method. Zeta-crystallin shows much greater binding intensity for ss-DNA and for ds-Z-DNA than for ds-B-DNA. It also reacts slightly more with ds-Z-DNA than ss-DNA. Therefore, we speculate that zeta-crystallin may act as a transcriptional enhancer (outer lens cortex), possibly binding to Z-DNA regulatory elements within lens crystallin genes. It may also act to protect DNA from endogenous DNase activity and as a DNA unwinding (destabilizing) protein also involved with transcription, occurring in normal adult bovine lens nucleated secondary fiber cells.
- Published
- 1998
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21. Echogenicity of hepatic versus portal vein walls revisited with histologic correlation.
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Wachsberg RH, Angyal EA, Klein KM, Kuo HR, and Lambert WC
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- Aged, Cadaver, Female, Humans, Liver diagnostic imaging, Male, Middle Aged, Ultrasonography, Hepatic Veins cytology, Hepatic Veins diagnostic imaging, Liver blood supply, Portal Vein cytology, Portal Vein diagnostic imaging
- Abstract
The portal vein wall typically is hyperechoic over a wide range of beam-vessel angles, whereas the hepatic vein wall is hyperechoic only when the incident beam and the vessel are perpendicular. This has been attributed to marked discrepancies in mural thickness, collagen content, or perivascular fat between portal and hepatic veins. We evaluated histologically the walls of portal and hepatic veins using three cadaveric livers. For vessels with luminal diameter above 2 to 3 mm, hepatic vein and portal vein wall thicknesses were similar such that portal vein walls were not more than 50% thicker than those of hepatic veins of comparable size. Hepatic vein walls were mostly composed of parallel, tightly packed collagen fibers. In contrast, portal vein walls were composed of loosely arrayed, nonparallel connective tissue fibers which were separated by multiple intervening spaces and only a minority of which were collagenous. Perivascular fat was not identified adjacent to intrahepatic vessels beyond the liver hilus. The marked differences in echogenicity between portal vein and hepatic vein walls typically observed at ultrasonography thus cannot be attributed to differences in mural thickness, collagen content, or perivascular fat between these vessels. Rather, the distinct composition of the hepatic vein wall renders it a specular reflector, which is hyperechoic only when the angle between the ultrasound beam and the vessel wall is close to 90 degrees, whereas the composition of the portal vein wall enables it to appear hyperechoic at a wide range of beam-vessel angles.
- Published
- 1997
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22. Localization of B-DNA and Z-DNA in terminally differentiating fiber cells in the adult lens.
- Author
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Gagna CE, Lambert WC, Kuo HR, and Farnsworth PN
- Subjects
- Adult, Animals, Crystallins analysis, DNA, Single-Stranded analysis, Dogs, Eosine Yellowish-(YS), Epithelium chemistry, Fluorescent Dyes, Histocytochemistry, Humans, Image Processing, Computer-Assisted, Immunohistochemistry, DNA analysis, Lens, Crystalline chemistry
- Abstract
We examined histochemically and immunohistochemically the distribution of B- and Z-DNA in the epithelium and terminally differentiating dog lens fiber cells. On the basis of anti-DNA antibody reactivity, qualitative and quantitative data on B- and Z-DNA in cells were determined. Anti-B-DNA immunoreactivity gradually declined throughout nucleated fibers, with a precipitous decrease at approximately 90 microns. Anti-Z-DNA antibody binding decreased with a sudden loss of immunoreactivity at approximately 90 microns. The pattern of anti-B- and Z-DNA staining correlates with the loss of alpha-crystallin immunoreactivity, the major lens crystallin, and decreased eosin staining of proteins. Germinative zone cell nuclei showed the highest DNA probe binding values, followed by the superficial fibers, central zone, middle fibers, and deep fibers. The presence of single-stranded (ss)DNA in deeper fibers was detected by anti-ss-DNA antibodies. This is indicative of DNA degradation. These observations suggest that a dramatic reorganization of lens fiber cells' supramolecular order occurs at approximately 90 microns, the phase transition zone.
- Published
- 1997
- Full Text
- View/download PDF
23. The quantification and distribution of nasal sebaceous glands using image analysis.
- Author
-
Michelson LN, Peck GC Jr, Kuo HR, Lambert WC, Cohen PJ, Adler US, and Peck GC
- Subjects
- Humans, Nose, Rhinoplasty, Sebaceous Glands physiology
- Abstract
The distribution of sebaceous glands in nasal skin is of interest because the presence of these adnexal structures significantly influences the outcome of healing. Using whole nasal skins dissected from cadavers, we prepared tissue sections from the nasal bridge to the nasal tip, both from the midline and lateral aspects. The sebaceous glands in these sections were analyzed for the following parameters: (1) size of the glands, (2) width of luminal cross-sections, and (3) depth of the glands. These parameters were studied using a Leitz Quantimet 500 Plus image analyzer and software to quantify the results. We found that the superior or proximal nasal skin contains fewer, smaller, more superficially located sebaceous glands. The inferior or distal nasal skin contains increased numbers of sebaceous glands which are markedly larger in size. The glands in the distal nose have larger lumina, are situated both superficially and deep in the dermis, and also occupy a greater percentage of the dermis. We identified an anatomical breakpoint on the nasal skin, marking the transition from superficial, small sebaceous glands to superficial-and-deep, enlarged glands. The columella was found to be similar to the proximal nasal skin.
- Published
- 1996
- Full Text
- View/download PDF
24. Xeroderma pigmentosum.
- Author
-
Lambert WC, Kuo HR, and Lambert MW
- Subjects
- DNA biosynthesis, DNA Adducts, DNA Damage, DNA Repair, Deoxyribonuclease I genetics, Deoxyribonuclease I metabolism, Humans, Mutagenesis genetics, Pyrimidines metabolism, Sunlight adverse effects, Ultraviolet Rays adverse effects, Xeroderma Pigmentosum metabolism, Xeroderma Pigmentosum pathology, Neoplasms, Radiation-Induced pathology, Precancerous Conditions pathology, Skin Neoplasms pathology, Xeroderma Pigmentosum genetics
- Abstract
Xeroderma pigmentosum is a rare, recessively transmitted disease associated with increased sensitivity to ultraviolet radiation in wavelengths found in sunlight, development of cancers in sun-exposed areas of the body in much larger numbers and much earlier in life than in normal individuals, and in some patients, neurologic deficiencies unrelated to sun exposure. Extensive cellular, biochemical, and molecular genetic studies in numerous laboratories have revealed that cells derived from patients with this disease have defective repair of ultraviolet-light-induced damage in cellular DNA, and that extensive genetic heterogeneity and numerous distinct genes are involved in the genetics of this disease and the etiopathogenesis of its associated changes. A number of these genes and gene products are now being, or have been, cloned, and their gene products characterized.
- Published
- 1995
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