Search results for " Hypoxia"
showing 10 items of 222 documents
Assessment of induced corneal hypoxia in diabetic patients
2002
Comparative Study Address correspondence and reprint requests to Dr. C. Creuzot-Garcher, Service d'Ophtalmologie, CHU, Hopital Général, 3 Rue du Faubourg Raines, BP 1519, 21033 Dijon, France. E-mail: Catherine.creuzot-garcher@chu-dijon.fr; To assess the control of corneal hydration in patients with diabetes during a contact lens-induced hypoxia. Corneal stress was induced in 15 patients with diabetes and 23 healthy patients by having them wear contact lenses for 2 hours. Pachymetries were measured and corneal parameters (percentage recovery per hour [PRPH], time for deswelling [T99%] and induced swelling [IS]) were calculated. In the mean time, tears were collected to assess the activity of…
Tumor oxygenation: a new predictive parameter in locally advanced cancer of the uterine cervix.
1993
Abstract Experimental evidence suggests that hypoxia may increase the malignant potential and reduce the sensitivity toward nonsurgical treatment modalities in solid rodent tumors. However, the importance of tumor hypoxia in human malignancies is still uncertain. We have developed a clinically applicable standardized procedure for the determination of intratumoral p O 2 in advanced cervical cancers by use of a computerized polarographic needle electrode histograph. To evaluate the significance of tumor oxygenation as a new oncologic parameter we initiated an open prospective clinical trial at the University of Mainz Medical Center in June 1989. Until October 1992 50 patients with advanced c…
CD15 immunostaining improves placental diagnosis of fetal hypoxia
2020
Fetal hypoxic events with unclear predictive value are a common indication for placenta examination. We evaluated whether the use of CD15 immunostaining can improve the assessment of severity and duration of fetal hypoxia.We compared placentas (37-42 gestational weeks) from stillborns/newborns with birth asphyxia (BA) and non-hypoxic newborns. Placental findings were studied in following groups: (1) acute BA (n = 11) due to placental abruption, (2) non-acute BA (n = 121) due to non-acute conditions, (3) non-BA (n = 46) in pregnancies with preeclampsia and gestational diabetes, and (4) controls (n = 30).A high expression of CD15 in feto-placental resistance vessels (FRVs) was present in non-…
Oxygenation Status of Gynecologic Tumors: What is the Optimal Hemoglobin Level?
2002
Tumor hypoxia has been linked to the development of treatment resistance, tumor progression, and poor prognosis. Since anemia is a major causative factor for the development of hypoxia, the association between blood hemoglobin concentration (cHb) and tumor oxygenation was examined in this study.Pretreatment O(2) tension (pO(2)) measurements were performed in 59 primary carcinomas of the uterine cervix in which a stringent histopathologic examination of the electrode tracks was mandatory in order to exclude measurements in necrotic, stromal or normal cervical tissue. In addition, pO(2) readings in twelve primary cancers and 17 local recurrences of vulvar cancers were included in this study. …
Tumor Blood Flow and O2 Availability during Hemodilution
1984
An insufficient and heterogeneously distributed nutritive blood flow leads to an inadequate and nonuniform supply of O2 and substrates in many solid tumors (Vaupel, 1977, 1979, 1982). This deterioration of the supply conditions, which already occurs in very early growth stages and which is superimposed by a deterioration of diffusive transport during advanced growth stages, is paralleled by a decrease in the therapeutic efficacy of various cancer treatment modalities such as irradiation and chemotherapy with antiproliferative drugs. In the case of anticancer drugs, the efficiency may be reduced by affecting both pharmacokinetics and pharmacodynamics. In the latter case this is due to the de…
Extensive transcriptional complexity during hypoxia-regulated expression of the myoglobin gene in cancer.
2013
Recently, the ectopic expression of myoglobin (MB) was reported in human epithelial cancer cell lines and breast tumor tissues, where MB expression increased with hypoxia. The better prognosis of MB-positive breast cancer patients suggested that the globin exerts a tumor-suppressive role, possibly by impairing mitochondrial activity in hypoxic breast carcinoma cells. To better understand MB gene regulation in cancer, we systematically investigated the architecture of the human MB gene, its transcripts and promoters. In silico analysis of transcriptome data from normal human tissues and cancer cell lines, followed by RACE-PCR verification, revealed seven novel exons in the MB gene region, mo…
Endothelial VEGFR-3 expression in colorectal carcinomas is associated with hematogenous metastasis
2009
Vascular endothelial growth factor receptor 3 (VEGFR-3) is a major inducer of lymphangiogenic signalling and seems to be involved also in angiogenesis. Since both processes are closely linked with tumor metastasis this study investigated the expression of VEGFR-3 in tumor-associated vessels in colorectal carcinomas and evaluated its relevance for lymphogenous and hematogenous metastasis. In a comparative study between microvascular endothelial cells isolated from the tumor (HCTEC) and the corresponding non-neoplastic tissue (HCMEC) from five patients with colorectal cancer VEGFR-3 expression was measured using a specific ELISA. The expression pattern was individually different, with cases s…
Mineralization of bone-related SaOS-2 cells under physiological hypoxic conditions
2015
Inorganic polyphosphate (polyP) is a physiological energy-rich polymer with multiple phosphoric anhydride bonds. In cells such as bone-forming osteoblasts, glycolysis is the main pathway generating metabolic energy in the form of ATP. In the present study, we show that, under hypoxic culture conditions, the growth/viability of osteoblast-like SaOS-2 cells is not impaired. The addition of polyP to those cells, administered as amorphous calcium polyP nanoparticles (aCa-polyP-NP; approximate size 100 nm), significantly increased the proliferation of the cells. In the presence of polyP, the cells produce significant levels of lactate, the end product of anaerobic glycolysis. Under those conditi…
The role of hypoxia-induced factors in tumor progression.
2004
Abstract Learning Objectives After completing this course, the reader will be able to: Describe hypoxia-induced mechanisms for cell survival. Discuss hypoxia-induced gene expression. Relate hypoxia and glucose metabolism. Access and take the CME test online and receive 1 hour of AMA PRA category 1 credit atCME.TheOncologist.com Hypoxia is a common characteristic of locally advanced solid tumors that has been associated with diminished therapeutic response and, more recently, with malignant progression, that is, an increasing probability of recurrence, locoregional spread, and distant metastasis. Emerging evidence indicates that the effect of hypoxia on malignant progression is mediated by a…
Glucose metabolism of malignant cells is not regulated by transketolase-like (TKTL)-1.
2010
An isoenzyme of transketolase, transketolase-like (TKTL)-1, has been hypothesized to play a pivotal role in the pathophysiology of malignant tumors. Available data are based on the detection of the putative TKTL-1 protein with one particular mouse monoclonal anti-TKTL-1 antibody, clone JFC12T10. In this study it was demonstrated that a) JFC12T10 detects multiple unspecific bands in Western blots, b) a 75-kDa band hitherto referred to as TKTL-1 corresponds to a nuclear protein and c) immunohistochemical detection of TKTL-1 in benign leiomyomas yields an expression pattern identical to that found in a variety of malignant tumors. In RT-PCR assays, using three different primer pairs for transk…