Publications by authors named "Dimitrios Hatzis"

2 Publications

  • Page 1 of 1

Effects of transgene expression of superoxide dismutase and glutathione peroxidase on pulmonary epithelial cell growth in hyperoxia.

Am J Physiol Lung Cell Mol Physiol 2005 Apr 3;288(4):L718-26. Epub 2004 Dec 3.

CardioPulmonary Research Institute, Winthrop University Hospital, 222 Station Plaza North, Suite 604, Mineola, NY 11501, USA.

Prolonged exposure to supraphysiological oxygen concentrations results in the generation of reactive oxygen species, which can cause significant lung injury in critically ill patients. Supplementation with human recombinant antioxidant enzymes (AOE) may mitigate hyperoxic lung injury, but it is unclear which combination and concentration will optimally protect pulmonary epithelial cells. First, stable cell lines were generated in alveolar epithelial cells (MLE12) overexpressing one or more of the following AOE: Mn superoxide dismutase (MnSOD), CuZnSOD, or glutathione peroxidase 1. Next, A549 cells were transduced with 50-300 particles/cell of recombinant adenovirus containing either LacZ or each of the three AOE (alone or in combination). Cells were then exposed to 95% O(2) for up to 3 days, with cell number and viability determined daily. Overexpression of either MnSOD (primarily mitochondrial) or CuZnSOD (primarily cytosolic) reversed the growth inhibitory effects of hyperoxia within the first 48 h of exposure, resulting in a significant increase in viable cells (P < 0.05), with 1.5- to 3-fold increases in activity providing optimal protection. Protection from mitochondrial oxidation was confirmed by assessing aconitase activity, which was significantly improved in cells overexpressing MnSOD (P < 0.05). Data indicate that optimal protection from hyperoxic injury occurs in cells coexpressing MnSOD and glutathione peroxidase 1, with prevention of mitochondrial oxidation being a critical factor. This has important implications for clinical trials in preterm infants receiving SOD supplementation to prevent acute and chronic lung injury.
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April 2005

The approach to conception for women with seminal plasma protein hypersensitivity.

Am J Reprod Immunol 2004 Jul;52(1):42-4

The New York Presbyterian Hospital, New York, NY, USA.

Problem: Allergic reactions to human seminal plasma protein has become increasingly recognized in the medical community. Treatment for most allergic conditions usually begins with avoidance of the offending allergen. For women with seminal plasma protein hypersensitivity (SPH) who desire to conceive, this approach is unacceptable. We describe a case report of a woman with an SPH who desired to have unprotected intercourse in order to conceive.

Methods: The patient underwent skin prick testing to her fiancé's fresh undiluted semen. Serum-specific IgG and IgE was performed by ELISA to the fiancé's whole seminal plasma and seminal plasma proteins (SPP). The patient underwent an intravaginal graded challenge to whole seminal fluid. Intrauterine insemination with washed spermatozoa was attempted but in vitro fertilization was subsequently required.

Results: The patient had a positive prick test to whole seminal plasma but negative specific IgG and IgE ELISA to SPPs. An intravaginal graded challenge to whole seminal plasma was well tolerated. However, she experienced a subsequent severe local reaction after unprotected intercourse. She deferred treatment with systemic desensitization to relevant SPPs. She failed intrauterine insemination but successfully conceived with in vitro fertilization.

Conclusion: This case report emphasizes that SPH is not associated with sterility. It also indicates that whole seminal plasma graded challenge is not uniformly successful for the treatment of SPH.
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July 2004