Friday

Predictive value of mid-trimester amniotic fluid high-sensitive C-reactive protein, ferritin, and lactate dehydrogenase for fetal growth restriction

BACKGROUND: Fetal growth restriction (FGR) is surprisingly common with placental dysfunction occurring in about 3% of pregnancies and despite advances in obstetric care, FGR remains a major problem in developed countries.

AIM: The purpose of this study is to find out the predictive value of amniotic fluid high sensitive C-reactive protein (hs-CRP), ferritin , and lactate dehydrogenase (LDH) for FGR.

MATERIALS AND METHODS: This prospective strategy of this study has been conducted on pregnant women who underwent genetic amniocentesis between 15th and 20th weeks of gestation. All patients were followed up on until delivery. Patients with abnormal karyotype and iatrogenic preterm delivery for fetal and maternal indications were excluded. The samples were immediately sent to laboratory for cytogenetic and biochemical examination. Non-parametric tests and receiver-operator characteristic curve analysis were used for statistical purpose.

RESULTS: A significant correlation between incremental amniotic fluid alpha fetoprotein (alphaFPr) and LDH levels and FGR at gestational weeks 15th-20th was found out. We also found an optimum cut-off value> 140 IU/L for the amniotic fluid LDH concentration with a sensitivity of 87.5% and a specificity of 82.4% for the prediction of FGR.

CONCLUSION: Once the LDH value is confirmed, it could serve as a prediction factor for FGR at the time of genetic amniocentesis at gestational weeks 15-20.

Indian J Pathol Microbiol. 2009 Oct-Dec;52(4):498-500.

Predictive value of mid-trimester amniotic fluid high-sensitive C-reactive protein, ferritin, and lactate dehydrogenase for fetal growth restriction.
Borna S, Abdollahi A, Mirzaei F.

Department of Gynecology and Obstetrics, Tehran University/ Medical of Science, Iran

Wednesday

Serum lactate dehydrogenase (LDH) level as a prognostic factor for the patients with advanced gastric cancer

Background: Though serum LDH level is frequently elevated in the patients with advanced gastric cancer, its clinical significance is still elusive. Moreover, the relationship between the change of serum LDH level after chemotherapy and the response to the treatment has not been studied, yet. We analyzed serum LDH level as a prognostic factor for the patients with advanced stomach cancer.

Methods: We assessed serum LDH level before chemotherapy for the patients who were planned to receive palliative chemotherapy. We re-assessed their serum LDH level at the time when the response to chemotherapy was evaluated after 2–4 cycles of treatment. The survival duration and the response to chemotherapy for the patients with low serum LDH level were compared to the survival duration and the response to chemotherapy for the patients with high serum LDH level. The relationship between the change of serum LDH level and the response to the treatment was evaluated, too. Results: Total 118 patients were entered into this study and 114 patients were evaluable for their response to chemotherapy.

Pre-treatment serum LDH level was normal in 88 patients and elevated in 30 patients. The response rate in the patients with high serum LDH level was significantly higher than the response rate in the patients with normal serum LDH level (34.5% versus 15.3%, p < 0.05). However, the patients with normal serum LDH level lived longer than the patients with high serum LDH level (median: 378 days versus 206 days, p < 0.001). The normalizing of the elevated serum LDH level after chemotherapy was related to the good response to treatment (response rate 50.0% versus 18.8%, p < 0.05).

Conclusions: For the patients with advanced gastric cancer, high serum LDH level was related to better response to chemotherapy but shorter survival duration. The normalization of elevated serum LDH level after chemotherapy was related to good response to treatment.

H. Lee, Y. Yuh and S. Kim
Sanggyepaik Hospital, seoul, Republic of Korea
Journal of Clinical Oncology, 2009 ASCO Annual Meeting Proceedings (Post-Meeting Edition).
Vol 27, No 15S (May 20 Supplement), 2009: e15621

Thursday

Lactate dehydrogenase isozymes in skeletal muscle of patients with chronic obstructive pulmonary disease]

INTRODUCTION AND OBJECTIVES: In patients with chronic obstructive pulmonary disease (COPD), lactate dehydrogenase (LDH) levels in skeletal muscles are normal or tend to be elevated; on exercise, these levels increase more rapidly than in individuals without COPD. As it is likely that concentrations of LDH isozymes LDH(4) and LDH(5) are elevated in such patients, we measured those isozymes in peripheral muscle of patients with COPD.

PATIENTS AND METHODS: Eighteen patients with COPD and 10 healthy nonsmokers were included in the study. Spirometry and the 6-minute walk test were performed, and a biopsy of the quadriceps muscle was taken to measure levels of both total LDH and LDH isozymes by agarose gel electrophoresis and to classify the types of muscle fibers.

RESULTS: Controls and patients had similar concentrations of total LDH (mean [SE], 130 [30]micromol/min/g vs 152 [50]micromol/min/g, respectively) and LDH isozymes. A subgroup of 5 patients showed increased levels of isozymes LDH(1), LDH(2), and LDH(3), with decreased LDH(5) levels; these patients were women and had a lower oxygen saturation. The LDH(5) level was directly correlated with the 6-minute walk test and oxygen saturation. The percentage of type IIA fibers correlated directly with LDH(3) and LDH(4) concentrations whereas type IIX fibers were inversely correlated with LDH(3) concentration.

CONCLUSION: Measurement of LDH isozyme concentrations enabled a subgroup of patients to be identified with a higher concentration of cardiac isoenzymes and lower concentration of muscle isoenzymes, a situation which might indicate adaptation that favors aerobic metabolism.

Sección de Adaptación Muscular, Instituto de Medicina Experimental, Universidad Central de Venezuela, Caracas, Venezuela

Friday

Lactate dehydrogenase-5 (LDH-5) expression in human gastric cancer: association with hypoxia-inducible factor (HIF-1alpha) pathway, angiogenic factors

BACKGROUND: Lactate-dehydrogenase-5 (LDH-5) is an important isoenzyme converting pyruvate to lactate under hypoxic conditions and might play an important role in the development and progression of malignancies. However, the role of Lactate-dehydrogenase-5 (LDH-5) in gastric cancer is still unclear. In this study, we investigated the clinical significance of LDH-5 expression in gastric carcinoma.

METHODS: LDH-5 expression in 152 patients with different grade and stage gastric carcinoma was analyzed by immunohistochemistry. In addition, hypoxia-inducible factor 1alpha (HIF-1alpha) as a marker of tumor hypoxia, as well as vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) as angiogenesis parameters were also assessed in this study. Correlations between the expression of investigated proteins and various clinicopathological factors including survival were determined.

RESULTS: There were 94 cases (61.8%) showing high LDH-5 expression, and 95 patients (62.5%) had high HIF-1alpha expression. Positive correlation was found between LDH-5 expression and HIF-1alpha, VEGF, and COX-2. The overexpression of LDH-5 was more prevalent in advanced tumors having positive vessel invasion. Patients with overexpression of LDH-5 showed far lower disease-free (63.5% vs 82.7%) and overall (56.3% vs 78.4%) survival rates compared with patients with low LDH-5 expression. HIF-1alpha expression was shown to have no significance on survival. In multivariate analysis, high LDH-5 expression kept its independence as a negative prognostic indicator.

CONCLUSION: The results of the current study show that LDH-5 expression may be a useful prognostic factor for patients with gastric carcinoma.

Multipurpose peptide tags for protein isolation

A multifunctional peptide tag (HYDHYD) consisting of histidine, tyrosine and aspartate residues was fused to the N-terminal ends of green fluorescent protein (GFP), lactate dehydrogenase (LDH) and "http://www.leebio.com/products.php?search=hemoglobin">human hemoglobin (Hb), proteins which were subjected to ion-exchange chromatography (IEC), aqueous two-phase system partition, immobilized metal-ion affinity chromatography (IMAC), and hydrophobic interaction chromatography (HIC). Tagged GFP was retained significantly longer (>1 column volume) in both HIC and IEC. It exhibited 3× greater partition in favor of the hydrophobic phase in a two-phase system and 96% could be bound to an IMAC column which did not bind native GFP.

ARTICLE

Thursday

A Nitric Oxide–Inducible Lactate Dehydrogenase Enables Staphylococcus aureus to Resist Innate Immunity

Staphylococcus aureus is one of the most successful human pathogens, colonizing 2 billion individuals worldwide and causing invasive infections even in immunocompetent hosts. S. aureus can evade multiple components of host innate immunity, including the antimicrobial radical nitric oxide (NO) produced by activated phagocytes. We show that S. aureus is capable of metabolically adapting to nitrosative stress by expressing an NO-inducible L-lactate dehydrogenase (ldh1, SACOL0222) divergently transcribed from the NO-detoxifying flavohemoglobin (hmp). L-Lactate production allows S. aureus to maintain redox homeostasis during nitrosative stress and is essential for virulence. NO-inducible lactate dehydrogenase activity and NO resistance distinguish S. aureus from the closely related commensal species S. epidermidis and S. saprophyticus.

Tuesday

A bioassay for the simultaneous measurement of metabolic activity, membrane integrity, and lysosomal activity in cell cultures

The aim of this study was the development of an in vitro bioassay that combines several endpoints of general cytotoxicity for the screening of compounds or mixtures of compounds with potential bioactivity. The Alamar Blue assay was employed to assess metabolic activity, the Neutral Red assay was used for the assessment of membrane function and lysosomal activity, and the lactate dehydrogenase leakage assay was employed for the assessment of membrane integrity. Each assay was performed separately and in combination using a human fibroblast cell line (MRC-5). Three fungal secondary metabolites of different chemistry that affect different cellular targets were tested as model compounds: deoxynivalenol, enniatin B1, and 2-amino-14,16-dimethyloctadecan-3-ol. The obtained inhibitive compound concentrations for the assays performed separately and in combination were not significantly different (P < 0.05, n = 9). The combination of several cytotoxicity endpoints in a single assay increases the chance that potential bioactive/cytotoxic compounds are discovered during the screening of mixtures of natural compounds (e.g., extracts from fungal cultures or plants) when one endpoint fails and, at the same time, might give some basic information on the cellular target.

ARTICLE