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Chen JY, Peng Q, Jodl HJ. Infrared spectral comparison of 5-aminolevulinic acid and its hexyl ester. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2003; 59:2571-2576. [PMID: 12963453 DOI: 10.1016/s1386-1425(03)00011-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
5-aminolevulinic acid (ALA) and its hexyl ester (ALA-H) are bioorganic molecules, now used as drugs in the study and clinical application of photodynamic therapy (PDT). Their infrared spectra were reported in first time here. The spectral characteristic was found well correlated to their structure feature. The strong peaks of C=O, C-H(2) and O-H band were shown in ALA spectrum. While in case of ALA-H, besides the vibration modes of C=O and CH(2) the additional CH(3) infrared peaks appeared, which correspond with their structural difference. Thus the infrared spectrum could be used to detect and distinguish ALA and ALA-H, which have potential for the mechanism study of ALA and ALA-H based PDT in biological system. Using the infrared spectrum as the probe, the thermal effect on structure stability was detected. Below the temperature of 80 degrees C, the ALA and ALA-H are thermally stable in structure. When temperature reached 120 degrees C, the serious structure breaking (thermal decomposition) happened for both ALA and ALA-H.
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127
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Sayers I, Barton S, Rorke S, Sawyer J, Peng Q, Beghé B, Ye S, Keith T, Clough JB, Holloway JW, Sampson AP, Holgate ST. Promoter polymorphism in the 5-lipoxygenase (ALOX5) and 5-lipoxygenase-activating protein (ALOX5AP) genes and asthma susceptibility in a Caucasian population. Clin Exp Allergy 2003; 33:1103-10. [PMID: 12911785 DOI: 10.1046/j.1365-2222.2003.01733.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
BACKGROUND 5-Lipoxygenase (5-LO) and 5-lipoxygenase-activating protein (FLAP) are essential for cysteinyl-leukotriene (cys-LT) production, critical mediators in asthma. OBJECTIVE We sought to identify novel promoter polymorphisms within the FLAP (ALOX5AP) gene promoter and test the role of these and the previously identified 5-LO (ALOX5) Sp1 promoter polymorphism in asthma susceptibility. METHODS To assess genetic association with asthma phenotypes, we genotyped 341 Caucasian families (containing two asthmatic siblings) and non-asthmatic control subjects (n=184). Genetic association was determined by case-control and transmission disequilibrium test (TDT) analyses. To determine the functional role of polymorphisms on basal transcription, we generated ALOX5AP-promoter-luciferase constructs and transiently transfected human HeLa cells. RESULTS A novel G/A substitution at -336 bp and a poly(A) repeat (n=19 or 23) at position -169 to -146 bp were identified in the ALOX5AP promoter. Genotyping found the -336 A and poly(A19) alleles at frequencies of q=0.06 and 0.12, respectively. No ALOX5AP allele was associated with asthma or asthma-related phenotypes in case-control or TDT analyses. ALOX5AP-promoter-luciferase analyses did not support a functional role of the -336 or poly(A) polymorphism in determining basal transcription. The ALOX5 Sp1 polymorphism was predominantly homozygous wild-type 5/5 (frequency q=0.70) and heterozygous 4/5 (q=0.23) genotypes and no allele was associated with asthma or asthma-related phenotypes. CONCLUSION Taken together, these data do not support a significant role for these polymorphisms in genetic susceptibility to asthma in the Caucasian population.
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Beghé B, Barton S, Rorke S, Peng Q, Sayers I, Gaunt T, Keith TP, Clough JB, Holgate ST, Holloway JW. Polymorphisms in the interleukin-4 and interleukin-4 receptor alpha chain genes confer susceptibility to asthma and atopy in a Caucasian population. Clin Exp Allergy 2003; 33:1111-7. [PMID: 12911786 DOI: 10.1046/j.1365-2222.2003.01731.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND IL-4 by binding to its receptor (IL-4R) is essential for the development of airway inflammation present in asthma, through the induction of IgE synthesis in B cells and differentiation of T cells to a Th2 phenotype. OBJECTIVE To investigate the role of four common polymorphisms in the IL-4 (IL4-34CT and IL4-589CT) and IL-4Ralpha chain (IL4RAI50V and IL4RAQ576R) genes in conferring susceptibility to the development of atopy and/or asthma. METHODS Two polymorphisms in the IL-4 gene promoter, IL4-34CT and IL4-589CT, and two polymorphisms in the IL-4Ralpha chain gene, IL4RAI50V and IL4RAQ576R, have been genotyped using PCR-based methods in 341 asthmatic families and in 184 non-asthmatic adults recruited from the south of England. RESULTS Case-control analysis did not reveal differences in the distribution of the four polymorphisms between asthmatics and controls. However, the transmission disequilibrium test showed that the IL4-589 T allele was preferentially transmitted to asthmatic children (P=0.036) and that the IL4RAQ576 was preferentially transmitted to children with atopic asthma (P=0.018). Haplotype analysis showed a strong association between the IL4-34T/-589T haplotype and asthma per se (P=0.041), and a strong association between the IL4RA I50/Q576 haplotype and atopic asthma (P=0.006). CONCLUSION Our data suggest that polymorphisms in the IL-4 and IL-4Ralpha chain genes might play a role both conferring susceptibility to and modulating severity of atopy and asthma.
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Sullards MC, Wang E, Peng Q, Merrill AH. Metabolomic profiling of sphingolipids in human glioma cell lines by liquid chromatography tandem mass spectrometry. Cell Mol Biol (Noisy-le-grand) 2003; 49:789-97. [PMID: 14528916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Sphingolipids participate in membrane structure and signaling in neuronal cells, and an emerging strategy for control of gliomas is to inhibit growth and/or induce apoptosis using ceramide and ceramide analogs. Nonetheless, some sphingolipids (ceramides and sphingosine) induce and others (sphingosine 1-phosphate) inhibit apoptosis; therefore, when testing putative anti-cancer agents, it is critical to obtain precise knowledge of the types and quantities of not only the test compounds, but also their effects on endogenous species. Combination of liquid chromatography and tandem mass spectrometry affords a "metabolomic" profile of all of the intermediates of ceramide biosynthesis (3-ketosphinganine, sphinganine and dihydroceramides) and the direct products of ceramide metabolism (sphingomyelins and monohexosylceramides as well as sphingosine and sphingosine 1-phosphate). This method has been applied to four human glioma cell lines (LN18, LN229, LN319 and T98G), and differences in the amounts and types of sphingolipids were found. For example, LN229 and LN319 have approximately twice the sphingosine 1-phosphate of LN18 and T98G; LN229 and LN319 have more monohexosylceramides than lactosylceramides, whereas the opposite is the case for LN18 and T98G; and the fatty acyl chain distributions of the sphingolipids differ among the cell lines. The ability to obtain this type of "metabolomic" profile allows studies of how anti-cancer agents (especially sphingolipids and sphingolipid analogs) affect the amounts of these bioactive species, and may lead to a better understanding of the abnormal phenotypes of gliomas.
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Bennett GW, Bousquet B, Brown HN, Bunce G, Carey RM, Cushman P, Danby GT, Debevec PT, Deile M, Deng H, Deninger W, Dhawan SK, Druzhinin VP, Duong L, Efstathiadis E, Farley FJM, Fedotovich GV, Giron S, Gray FE, Grigoriev D, Grosse-Perdekamp M, Grossmann A, Hare MF, Hertzog DW, Huang X, Hughes VW, Iwasaki M, Jungmann K, Kawall D, Khazin BI, Kindem J, Krienen F, Kronkvist I, Lam A, Larsen R, Lee YY, Logashenko I, McNabb R, Meng W, Mi J, Miller JP, Morse WM, Nikas D, Onderwater CJG, Orlov Y, Ozben CS, Paley JM, Peng Q, Polly CC, Pretz J, Prigl R, Zu Putlitz G, Qian T, Redin SI, Rind O, Roberts BL, Ryskulov N, Shagin P, Semertzidis YK, Shatunov YM, Sichtermann EP, Solodov E, Sossong M, Steinmetz A, Sulak LR, Trofimov A, Urner D, Von Walter P, Warburton D, Yamamoto A. Measurement of the positive muon anomalous magnetic moment to 0.7 ppm. PHYSICAL REVIEW LETTERS 2002; 89:101804. [PMID: 12225185 DOI: 10.1103/physrevlett.89.101804] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2002] [Indexed: 05/23/2023]
Abstract
A higher precision measurement of the anomalous g value, a(mu)=(g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron, based on data collected in the year 2000. The result a(mu(+))=11 659 204(7)(5)x10(-10) (0.7 ppm) is in good agreement with previous measurements and has an error about one-half that of the combined previous data. The present world average experimental value is a(mu)(expt)=11 659 203(8)x10(-10) (0.7 ppm).
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Peng Q, Groebner R, Lao L, Schachter J, Schissel D, Wade M. Status of the Linux PC cluster for between-pulse data analyses at DIII-D. FUSION ENGINEERING AND DESIGN 2002. [DOI: 10.1016/s0920-3796(02)00027-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Schissel D, Finkelstein A, Foster I, Fredian T, Greenwald M, Hansen C, Johnson C, Keahey K, Klasky S, Li K, McCune D, Peng Q, Stevens R, Thompson M. Data management, code deployment, and scientific visualization to enhance scientific discovery in fusion research through advanced computing. FUSION ENGINEERING AND DESIGN 2002. [DOI: 10.1016/s0920-3796(02)00050-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Schmidbauer JM, Apple DJ, Peng Q, Arthur SN, Vargas LG. [Cloudiness of a PMMA intraocular lens. "Snowflake" degeneration]. Ophthalmologe 2002; 99:306-7. [PMID: 12058511 DOI: 10.1007/s003470100492] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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134
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Arthur S, Steed LL, Apple DJ, Peng Q, Howard G, Escobar-Gomez M. Scedosporium prolificans keratouveitis in association with a contact lens retained intraocularly over a long term. J Clin Microbiol 2001; 39:4579-82. [PMID: 11724890 PMCID: PMC88594 DOI: 10.1128/jcm.39.12.4579-4582.2001] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Scedosporium prolificans is a soil saprophyte that is associated with a large variety of infectious processes and with respiratory colonization in immunocompetent and immunocompromised patients. We report the first described case of S. prolificans keratouveitis associated with the intraocular long-term retention of a contact lens in a 76-year-old female patient.
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Wu GJ, Wu MW, Wang SW, Liu Z, Qu P, Peng Q, Yang H, Varma VA, Sun QC, Petros JA, Lim SD, Amin MB. Isolation and characterization of the major form of human MUC18 cDNA gene and correlation of MUC18 over-expression in prostate cancer cell lines and tissues with malignant progression. Gene 2001; 279:17-31. [PMID: 11722842 DOI: 10.1016/s0378-1119(01)00736-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Ectopical expression of huMUC18, a cell adhesion molecule in the immunoglobulin gene superfamily, causes a non-metastatic human melanoma cell line to become metastatic in a nude mouse system. To determine if MUC18 expression correlates with the development and malignant progression of prostate cancer, we investigated differential expression of human MUC18 (huMUC18) in normal prostate epithelial cells, prostate cancer cell lines, and prostatic normal and cancer tissues. We cloned and characterized the human MUC18 (huMUC18) cDNA gene from three human prostate cancer cell lines and three human melanoma cell lines. The cDNA sequences from the six human cancer cell lines were identical except differences in one to five nucleotides. The deduced amino acid sequences of the longest ORF were 646 amino acids that were identical in these cDNAs except for one to three amino acid residues. The amino acid sequences of all our huMUC18 cDNA genes are similar to that cloned by other group (GenBank access #M28882) except differences in the same seven amino acids. We conclude that huMUC18 cDNA gene reported here represents the gene product from a major allele. The MUC18 mRNA and protein was expressed in three metastatic prostate cancer cell lines (TSU-PR1, DU145, and PC-3), but not in one non-metastatic prostate cancer cell line (LNCaP.FGC). The expression of huMUC18 in these four cell lines is positively related to their extent of in vitro motility and invasiveness and in vivo metastasis in nude mice. HuMUC18 protein was also expressed at high levels in extracts prepared from tissue sample sections containing high grade prostatic intraepithelial neoplasia (PIN), but weakly expressed in extracts prepared from cultured primary normal prostatic epithelial cells and the normal prostate gland. Immunohistochemical analysis showed that huMUC18 was expressed at higher levels in the epithelial cells of high-grade PIN and prostatic carcinomas, and in cells of a perineural invasion, a lymph node, and a lung metastases compared to that in normal or benign hyperplastic epithelium (BPH). We therefore conclude that MUC18 expression is increased during prostate cancer initiation (high grade PIN) and progression to carcinoma, and in metastatic cell lines and metastatic carcinoma. Increased expression of MUC18 is implicated to play an important role in developing and malignant progression of human prostate cancer. Furthermore, the lacking of predominant cytoplasmic membrane expression of MUC18 appeared to correlate with malignant progression of prostate cancer.
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MESH Headings
- Amino Acid Sequence
- Antigens, CD
- Antigens, Surface/genetics
- Antigens, Surface/metabolism
- Base Sequence
- CD146 Antigen
- Cell Membrane/metabolism
- Cell Movement
- Cytoplasm/metabolism
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- Disease Progression
- Gene Expression Regulation, Neoplastic
- Humans
- Immunohistochemistry
- Male
- Melanoma/genetics
- Melanoma/pathology
- Membrane Glycoproteins
- Molecular Sequence Data
- Neoplasm Invasiveness
- Neural Cell Adhesion Molecules
- Prostate/chemistry
- Prostate/cytology
- Prostate/metabolism
- Prostatic Neoplasms/genetics
- Prostatic Neoplasms/pathology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Tumor Cells, Cultured
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Schmidbauer JM, Apple DJ, Auffarth GU, Peng Q, Pandey SK, Werner L, Escobar-Gomez M, Vargas LG. [Complication profiles of posterior chamber intraocular lenses IOL). An analysis of 586 foldable and 2077 rigid explanted intraocular lenses]. Ophthalmologe 2001; 98:1029-35. [PMID: 11729733 DOI: 10.1007/s003470170021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Foldable intraocular lenses (IOL) have become increasingly preferred choice for IOL implantation after cataract removal. However, both foldable as well as rigid IOLs are not yet complication-free and may need explanation. MATERIAL AND METHODS A total of 2663 explanted posterior chamber IOLs (PCIOLs) were accessioned at the Center for Research on Ocular Therapeutics and Biodevices between January 1988 and September 2000. The lenses were examined grossly using a Leitz/Wild M-8-Zoom stereomicroscope. The clinical reasons for explanation were documented for foldable as well as for rigid lenses. RESULTS Of a total of 2663 explanted PCIOLs, 586 were foldable lenses and 2077 were rigid PMMA lenses The most frequent reason for explantation of all 2663 IOLs studied was decentration/dislocation. Optic and haptic damage and posterior capsule rupture were significantly more often a reason for explantation in several foldable designs compared to rigid PCIOLs. Whereas rigid designs lead more often to corneal decompensation. The percentage of explanted IOLs because of inflammatory reactions decreased significantly from 1994 to 2000. CONCLUSIONS The complication profiles of rigid and foldable IOLs revealed some apparent differences due to the nature of the IOL biomaterials and designs. IOL optic/haptic damage was a common complication for foldable IOLs, whereas it was only discovered in single digits for rigid PMMA IOLs. The possible explanation for this is, that the soft and flexible biomaterials, from which all the foldable IOLs were manufactured, are easier to be damaged during folding, unfolding and insertion procedure. In our opinion this relative disadvantage of foldable IOLs is by far outweighed by the numerous advantages of the small incision cataract surgery. The decreasing inflammatory reactions can be explained by advances in surgical techniques, especially the secure in-the-bag fixation of IOLs.
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Peng Q. [A brief history of ophthalmology in the pre-Qin period] (Chi). ZHONGHUA YI SHI ZA ZHI (BEIJING, CHINA : 1980) 2001; 18:75-8. [PMID: 11621546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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138
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Vargas LG, Peng Q, Escobar-Gomez M, Schmidbauer JM, Apple DJ. Overview of modern foldable intraocular lenses and clinically relevant anatomy and histology of the crystalline lens. Int Ophthalmol Clin 2001; 41:1-15. [PMID: 11481534 DOI: 10.1097/00004397-200107000-00003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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139
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Arthur SN, Peng Q, Escobar-Gomez M, Apple DJ. Silicone oil adherence to silicone intraocular lenses. Int Ophthalmol Clin 2001; 41:33-45. [PMID: 11481538 DOI: 10.1097/00004397-200107000-00005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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140
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Peng Q, Apple DJ, Arthur SN, Merritt JH, Escobar-Gomez M, Hoddinott DS. Snowflake opacification of poly(methyl methacrylate) intraocular lens optic biomaterial: a newly described syndrome. Int Ophthalmol Clin 2001; 41:91-107. [PMID: 11481542 DOI: 10.1097/00004397-200107000-00009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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141
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Schmidbauer JM, Vargas LG, Peng Q, Escobar-Gomez M, Werner L, Arthur SN, Apple DJ. Posterior capsule opacification. Int Ophthalmol Clin 2001; 41:109-31. [PMID: 11481543 DOI: 10.1097/00004397-200107000-00010] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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142
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Arthur SN, Peng Q, Apple DJ, Escobar-Gomez M, Bianchi R, Pandey SK, Werner L. Effect of heparin surface modification in reducing silicone oil adherence to various intraocular lenses. J Cataract Refract Surg 2001; 27:1662-9. [PMID: 11687368 DOI: 10.1016/s0886-3350(01)00891-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE To evaluate surface properties of various intraocular lenses (IOLs), including a newly fabricated heparin-surface-modified (HSM) silicone IOL, with special reference to their efficiency in reducing potential silicone oil adherence to the IOL optics. SETTING Center for Research on Ocular Therapeutics and Biodevices, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS Five groups of rigid and foldable IOLs were analyzed in an in vitro test for the percentage of silicone oil adherence: a single-piece foldable hydrophilic-acrylic IOL (n = 9); a single-piece rigid poly(methyl methacrylate) (PMMA) IOL with HSM coating of the lens optic (n = 9); a 3-piece foldable silicone optic IOL with HSM coating of the optic (n = 10); a single-piece standard rigid PMMA IOL (n = 7); and a standard 3-piece foldable silicone optic IOL (n = 9). After the IOLs were immersed in water and then in silicone oil, gross photographs taken. Image analysis was performed to evaluate the percentage of silicone oil coverage of the anterior and posterior surfaces of each IOL optic. RESULTS The mean silicone oil coverage of the hydrophilic-acrylic IOLs was 5.6% +/- 2.5% (SD); of the HSM PMMA IOLs, 6.2% +/- 4.3%; of the HSM silicone optic IOLs, 6.7% +/- 3.2%; and of the standard PMMA IOLs, 20.3% +/- 13.3%. The mean silicone oil coverage was greatest on the standard silicone optic IOLs, 98.2% +/- 3.1%. CONCLUSIONS Intraocular lenses with a hydrophilic optic have less tendency toward adherence to silicone oil than more hydrophobic designs. A foldable silicone IOL with heparin surface modification can significantly reduce potential silicone oil adherence, comparable to the level achievable with the rigid HSM PMMA designs. Two new foldable IOL styles, the HSM silicone IOL and IOLs in the general class of hydrophilic-acrylic, were highly efficacious in reducing silicone oil adherence. There is now a real choice of foldable lenses for patients with actual or potential vitreoretinal diseases.
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Schmidbauer JM, Vargas LG, Apple DJ, Auffarth GU, Peng Q, Arthur SN, Escobar-Gomez M. [Millenniums update on posterior capsule opacification (PCO) scores, centration, biocompatibility and fixation of foldable intraocular lenses (IOL) - an analysis of 1,221 pseudophakic post mortem globes]. Klin Monbl Augenheilkd 2001; 218:649-57. [PMID: 11706380 DOI: 10.1055/s-2001-18386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND The ongoing and fast evolution of foldable IOL designs established the necessity to evaluate the different abilities of each lens style. The large IOL database (over 16,500 specimens) acquired in our laboratory, has permitted us to perform a clinico-pathological analysis on pseudophakic autopsy globes provided from sources worldwide, especially many Lions Eye banks in the United States. MATERIAL AND METHODS We analyzed 6 foldable IOL styles commonly implanted in the United States, using one type of rigid IOL design (1-piece design rigid PMMA optics) as a comparison group. Posterior capsule opacification (PCO) score, decentration, fixation, presence or absence of a Nd:YAG laser posterior capsulotomy and area and intensity of Soemmerring's ring formation was discerned by examination under an operating microscope using the Miyake-Apple posterior photographic technique. RESULTS The four lenses with the lowest rates ranging between 3.8 % and 21.7 % are modern designs, mostly implanted after 1992. The two lenses with the higher rates ranging between 23.1 % and 30.4 %, were all older designs, already prevalent prior to 1992. IOL fixation with both haptics in the capsular bag showed the best centration values and PCO scores. Our studies to date have shown in a preliminary fashion that the AcrySoftrade mark IOL displays the the lowest (best) biocompatibility score. CONCLUSIONS Entering the new millenium, with evolution of modern surgical techniques and IOL designs, the incidence of the two major complications of cataract surgery, decentration and PCO are now finally diminishing.
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Peng Q, Soler AM, Warloe T, Nesland JM, Giercksky KE. Selective distribution of porphyrins in skin thick basal cell carcinoma after topical application of methyl 5-aminolevulinate. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2001; 62:140-5. [PMID: 11566277 DOI: 10.1016/s1011-1344(01)00173-7] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Topical photodynamic therapy (PDT) of superficial basal cell carcinoma (BCC) with 5-aminolevulinic acid (ALA) has achieved promising clinical results. However, the efficacy of this therapy for thick BCC is dramatically decreased by a limited diffusion of hydrophilic ALA into the tumor. Lipophilic esters of ALA may enhance their penetration into the lesion. In this randomized, open clinical study, microscopic fluorescence photometry incorporating a light-sensitive thermo-electrically cooled charge-coupled device (CCD) camera was employed to investigate the penetration of methyl 5-aminolevulinate-induced porphyrin fluorescence in thick BCC lesions. Both the distribution pattern and the amount of porphyrins in 32 lesions of 16 patients were studied after topical application of 16, 80 or 160 mg/g of methyl 5-aminolevulinate for 3 or 18 h. A highly selective and homogeneous distribution of methyl 5-aminolevulinate-induced porphyrin fluorescence was seen in all lesions studied, with much less fluorescence in the adjacent normal skin tissues. In lesions of up to 2 mm thickness the application of 160 mg/g methyl 5-aminolevulinate for 3 h showed the highest ratio of porphyrin fluorescence depth to tumor depth (0.98+/-0.04), thus providing a biologic rationale for a clinical PDT trial with this regimen.
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Schmidbauer JM, Werner L, Apple DJ, Pandey SK, Izak AM, Trivedi RH, Macky TA, Auffarth GU, Peng Q, Arthur SN, Escobar-Gomez M, Ma L, Vargas LG. [Postoperative opacification of posterior chamber intraocular lenses - a review]. Klin Monbl Augenheilkd 2001; 218:586-94. [PMID: 11590465 DOI: 10.1055/s-2001-17635] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Postoperative opacification of intraocular lenses (IOLs) is a very unpleasant complication for the ophthalmic surgeon and the patient. We report on our experiences with opacification of different foldable IOL designs and rigid poly (methyl methacrylate) (PMMA) posterior chamber lenses.1. Snowflake degeneration of PMMA IOLs: This condition is an unanticipated and surprising late postoperative finding 8 to 15 years after implantation. In our opinion, this complication is probably not related to the PMMA biomaterial itself, but rather it appears to represent a manufacturing problem that has affected a selected, albeit large number of lenses manufactured in the 1980s-mid 1990s.2. Degeneration of UV absorber material and calcium deposits within the optic of hydrophilic IOLs: Two years postoperatively degenerations of UV absorber material and calcium deposits within the optic of single piece hydrophilic acrylic lenses SC60B-OUV manufactured by MDR (Medical developmental research Inc. Clearwater FL, USA) can occur. Although the precise mechanism is not fully known, it was assumed that these opacifications are due to premature aging of the UV blocking agent incorporated in the lens biomaterial and calcification.3. Calcification on the surface of the Bausch & Lomb Hydroviewtrade mark IOLs: Twelve to 15 months postoperatively granular surface calcifications in Hydroviewtrade mark IOLs occured. The mechanism is not fully understood. According to Bausch and Lomb studies, part of the components of the packaging contained silicone, which may have come off the packaging onto the lens optic, where it then appears to be a catalyst for calcium precipitation. The manufacturer has correlated a change in packaging with the appearance of the opacification. The manufacturer now believes that this problem has been solved. However, final verification will require a careful 1 - 2 years clinical study.4. Glistenings in the hydrophobic acrylic AcrySoftrade mark IOLs: The time frame of glistenings in the AcrySoftrade mark IOLs is highly variable. It has been suggested that the occurrence of glistenings may be related to variations in the temperature of the lens just prior to and or during insertion into the eye. Formation of vacuoles may occur within the submersed acrylic polymer when there is a transient increase and then decrease in temperature during the surgical procedure. "Glistenings" may then subsequently form by ingress of anterior chamber fluid. Contrast sensitivity can been decreased in some patients, but clinically significant decrease of visual acuity has been rare.
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Peng Q, Wang G. [Determination of trace amount of cadmium with vapor generation and atomic absorption spectrometry]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 2001; 32:464-6. [PMID: 12536596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE This study aimed to establish a sensitive method for the determination of trace amount of cadmium. METHODS The reaction systems for the generation of volatile cadmium species were investigated with vapor generation and atomic absorption spectrometry. RESULTS It was found that potassium ferricyanide with hydroxylamine hydrochloride greatly enhanced the generation efficiency of the volatile species. The reaction parameters using ferricyanide-hydroxyamine-tetrahydroborate in acidic acqueous solution were optimized for efficient generation of volatile cadmium species. A detection limit (3 sigma blank, peak height mode) of 11 pg/ml was obtained under optimized conditions. The RSD of the determinations for 0.2 ngCd/ml was 3.4%. The effects of 33 diverse ions on the generation of the cadmium volatile species were investigated. The method was applied to the determination of cadmium in standard reference materials, the results obtained were in good agreement with the certified values. CONCLUSION The method can be applied to the determination of trace cadmium in environment and food samples.
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Luksiene Z, Eggen I, Moan J, Nesland JM, Peng Q. Evaluation of protoporphyrin IX production, phototoxicity and cell death pathway induced by hexylester of 5-aminolevulinic acid in Reh and HPB-ALL cells. Cancer Lett 2001; 169:33-9. [PMID: 11410323 DOI: 10.1016/s0304-3835(01)00559-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Production of protoporphyrin IX (PpIX) in human B-cell leukemia cell line (Reh) and T-cell lymphoma cell line (HPB-ALL) was studied by flow cytometry after incubation with 5-aminolevulinic acid (ALA) or its hexylester in vitro. Cell survival and cell death pathway were also investigated in these two cell lines by cell growth curves, flow cytometry, and electron microscopy after ALA hexylester-mediated photodynamic therapy. Both ALA and its hexylester could induce PpIX production in the two cell lines, but ALA hexylester was about 100 times more efficient than ALA. Reh cells appear to be more sensitive than HPB-ALL cells to ALA hexylester-mediated phototoxicity. Apoptosis was the major cell death pathway of Reh cells, while necrosis played a major role in the case of HPB-ALL cells.
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Peng Q, Warloe T, Moan J, Godal A, Apricena F, Giercksky KE, Nesland JM. Antitumor effect of 5-aminolevulinic acid-mediated photodynamic therapy can be enhanced by the use of a low dose of photofrin in human tumor xenografts. Cancer Res 2001; 61:5824-32. [PMID: 11479222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Practically all of the exogenous photosensitizers used for clinical photodynamic therapy (PDT) target mainly vasculature. Although effective in tumor destruction, they also, unavoidably, induce phototoxicity of normal tissues. Porphyrins synthesized endogenously from 5-aminolevulinic acid (ALA) accumulate within cells. Tumor eradication would be more efficient if both cellular components and vascular stroma of a tumor could be targeted. Thus, PDT with a mixture of ALA and Photofrin (Pf, a vessel-targeted sensitizer) may simultaneously destroy the two elements. Using chemical extraction assays, pharmacokinetics of ALA and ALA-induced porphyrins were studied in the plasma and tumors of nude mice bearing human WiDr and KM20L2 colonic carcinomas after an i.p. injection of 250 mg/kg body weight of ALA. Subsequently, PDT efficacy of the two tumor models with ALA, Pf, or with the two drugs in combination was evaluated. The phototoxic effects on tumor cells in vitro with the combined drugs was also determined. Moreover, histological and ultrastructural alterations of the treated tumors were investigated, and tumor cell clonogenicity was assessed as a function of time after in vivo PDT using an in vitro colony formation assay. Finally, the photosensitivity of normal skin tissue treated according to various protocols was compared. The amounts of ALA peaked at 0.5 h after administration in both plasma and WiDr tumor. The rates of ALA clearance seemed to follow a one-compartment model with half-lives of approximately 18 and 58 min in the plasma and tumor, respectively. About 100 and 60 times higher concentrations of ALA were needed to induce a given concentration of porphyrins in the plasma and tumor, respectively, although the plasma porphyrins may not only be released from blood cells but also from other organs. Similar kinetics of distribution patterns of ALA- and ALA methylester-induced porphyrins were found in the plasma and tumors, and the elimination rates were consistent with a two-compartment model. ALA induced much more porphyrins than ALA methylester in both plasma and tumors. Tumors PDT-treated with ALA plus Pf at a low dose (1 mg/kg) grew significantly more slowly than those treated with either of the drugs in both WiDr and KM20L2 models. However, the enhanced antitumor effect was not found in the tumor cells under in vitro conditions. Morphological studies demonstrated that PDT with the combined regimen resulted in necrosis of neoplastic cells and severe disruption of tumor microvasculature. This was supported by the findings obtained from the studies of in vivo PDT and in vitro clonogenic assay that showed a progressive reduction in tumor cell viability with times following PDT. Such a combined PDT protocol did not induce any phototoxicity in normal skin tissue. These data indicate that targeting both neoplastic cells and stroma with ALA and Pf (a low dose) can potentiate antitumor PDT effect with no risk of prolonged skin photosensitivity.
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Wild GJ, Kent AR, Peng Q. Dilation of Schlemm's canal in viscocanalostomy: comparison of 2 viscoelastic substances. J Cataract Refract Surg 2001; 27:1294-7. [PMID: 11524203 DOI: 10.1016/s0886-3350(01)00867-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To study the injection of viscoelastic material into Schlemm's canal adjacent to and 6.0 mm from the scleral flap during viscocanalostomy in an autopsy eye model. SETTING Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS Viscocanalostomy was performed in 8 postmortem human globes. Sodium hyaluronate (Healon GV or Healon5) was injected into 1 side of Schlemm's canal, with the other side serving as a control in some eyes. The eyes were prepared for light microscopic analysis, and serial pathologic sections were taken adjacent to the flap and 6.0 mm circumferentially from the flap. The area of Schlemm's canal was calculated and compared using t tests. RESULTS Injecting viscoelastic material enlarged the area of Schlemm's canal adjacent to and 6.0 mm from the flap significantly more than not injecting viscoelastic material. While there was no difference between the viscoelastic materials in dilating Schlemm's canal at the flap, with Healon5 there was a small but statistically significantly greater dilation 6.0 mm from the flap. No full-thickness breaks in the trabecular meshwork were noted adjacent to or 6.0 mm from the flap. CONCLUSION Injecting viscoelastic material significantly increased the cross-sectional area of Schlemm's canal and may play a role in the success of viscocanalostomy. Further study is needed to elucidate the mechanism of this procedure.
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Schmidbauer JM, Vargas LG, Apple DJ, Peng Q, Arthur SN, Escobar-Gomez M, Izak A. [Influence of surgery-related factors on the Nd:YAG laser capsulotomy rates of 3-piece silicone IOLs - analysis of 457 pseudophakic human globes obtained post mortem]. Klin Monbl Augenheilkd 2001; 218:523-7. [PMID: 11573152 DOI: 10.1055/s-2001-17133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
BACKGROUND The purpose of this study was to analyze any possible surgical reasons which may have had caused posterior capsule opacification in 3-piece silicone IOLs that had required Nd:YAG laser treatment. Special attention was given to 1) quality of cortical clean up, 2) type of haptic fixation, and 3) continuous curvilinear capsulorhexis (CCC) size and shape. MATERIALS AND METHODS Human eyes obtained post-mortem implanted with 3-piece silicone optic - PMMA haptic (SI 40 NB) and 3-piece silicone optic - Prolene haptic (SI 30 NB) designs IOLs, accessioned between January 1993 and December 2000 were evaluated by gross examination from behind under an operating microscope using the Miyake-Apple posterior photographic technique. The area and intensity of Soemmerring's ring and type of fixation was studied in 457 eyes. The mean diameter of the CCC and relation of the CCC edge to the optic rim were analyzed in 221 eyes. RESULTS 1) The amount of Soemmerring's ring formation was significantly larger in the group of IOLs requiring Nd:YAG capsulotomy in both the SI 40 NB and SI 30 NB design than in the IOLs without capsulotomies. 2) The percentage of not in-the-bag fixated IOLs in both the SI 40 NB and SI 30 NB design was larger in the "Nd:YAG groups", without being statistically significant. 3) The "Nd:YAG groups" showed a significant higher amount of non overlapping clock hours of the CCC edge in relation to the optic rim. CONCLUSION 1) The data confirm the clinical assumption that the incidence of PCO is correlated with the cortical clean up. 2) Our findings also support the clinical assumption, that poor IOL fixation increases the risk of PCO. 3) This study also verifies the relation of the CCC to PCO, namely a relatively small CCC covering the entire optic rim is best to reduce the Nd:YAG laser rate.
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